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11
2COMPREHENSIVE EXAMINATION
3CAD CAM
41. With incremental tool positioning, ____.
5a) each tool movement is made with reference to the last tool position
6b) all tool movement is measured from a fixed point or origin
7c) all tool movement is measured from a zero point
8d) No tool Movement
92. The point-to-point NC movement system ____.
10a) permits controlled tool travel along one axis at a time
11b) is used for operations performed at a fixed location in terms of a two-axis coordinate position
12c) precisely controls machine and tool movement at all times and in all planes
13d) All the answers
143. When the contour or continuous path system is used, ____.
15a) tool travel is controlled along one axis at a time
16b) machine and tool movements are precisely controlled at all times and in all planes
17c) tool movement from one point to the next does not have to follow a specific path
18d) No movement of tool
194. A point-to-point NC movement system ____.
20a) is typically used for drilling, punching, and spot welding.
21b) is used for operations at a fixed location in terms of a two-axis coordinate position
222
23c) tool movement from one position to the next does not have to follow a specific path
24d) All of the answers
255. Servo motors are ____.
26a) activated by pulses of current
27b) provide power to position the work
28c) connected to the lead and feed screws
29d) All of the answers
306. In a typical manufacturing environment, CAD modeling finds its role in:
31a) Design
32b) Drafting
33c) Manufacturing
34d) All of the answers
357. The screen is scanned from left to right, top to bottom all the time to generate graphics by
36a) Raster scan
37b) Random scan
38c) Vector scan
39d) All of the answers
408. The method which used either delta x or delta y, whichever is larger, is chosen as one raster unit to draw the line -the algorithm is called?
41a) Bresenham’s Line Algorithm
42b) DDA Line Algorithm
43c) Mid point Line Algorithm
44d) All of the answers
453
469. Which of the following line algorithms used integer only arithmetic to rasterize lines
47a) Bresenham’s Line Algorithm
48b) DDA Line Algorithm
49c) FFTW Line Algorithm
50d) Line clipping Algorithm
5110. In a CAD package, mirror image of a 2D point P (5, 10) is to be obtained about a line which passes through the origin and makes an angle of 45° counterclockwise with the X-axis. The coordinates of the transformed point will be
52a) (7.5, 5)
53b) (10, 5)
54c) (7.5, -5)
55d) (10, -5)
5611. During the execution of a CNC part program block NO20 GO2 X45.0 Y25.0 R5.0 the type of tool motion will be
57a) Circular Interpolation - clockwise
58b) Circular Interpolation - counterclockwise
59c) Linear Interpolation
60d) Rapid feed
6112. The shape of the Bezier curve is controlled by:
62a) Control points
63b) Knots
64c) End points
65d) All of the answers
664
6713. The degree of the B-spline with varying knot vectors:
68a) Increases with knot vectors
69b) Decreases with knot vectors
70c) Remains constant
71d) No influence with knot vectors
7214. Which of the following are the rules of programming NC machine tools in APT language?
731. only capital letters are used 2. A period is placed at the end of each statement 3. Insertion of space does not affect the APT word
74Select the correct answer using the codes given below:
75a) 1 and 2
76b) 2 and 3
77c) 1and 3
78d) 1 alone
7915. In an NC machining operation, the tool has to be moved from point (5, 4) to point (7, 2) along a circular path with centre at (5, 2). Before starting the operation, the tool is at (5, 4). The correct G and M code for this motion is
80a) N010 G03 X7.0 Y2.0 I5.0 J2.0
81b) N010 G02 X7.0 Y2.0 I5.0 J2.0
82c) N010 G01 X7.0 Y2.0 I5.0 J2.0
83d) N010 G00 X7.0 Y2.0 I5.0 J2.0
8416. In a CNC machine tool, encoder is used to sense and control
85a) spindle position
86b) table velocity
87c) spindle speed
885
89d) coolant flow
9017. In finish machining of an island on a casting with CNC milling machine, an end mill with 10mm diameter is employed. The corner points of the island are represented by (0, 0), (0, 30), (50,30), and (50, 0). By applying cutter radius right compensation, the trajectory of the cutter will be
91a) (-5, 0), (-5, 35), (55, 35), (55, -5), (-5, -5)
92b) (0, -5), (55, -5), (55, 35), (-5, 35), (-5, -5)
93c) (5, 5), (5, 25), (45, 25), (45, 5), (5, 5)
94d) (5, 5), (45, 5), (45, 25), (5, 25), (5, 5)
9518. Consider the following characteristics:
961. Single machine tool 2. Manual materials handling system 3. Computer control 4. Random sequencing of parts to machines
97Which of the above characteristics are associated with flexible manufacturing system?
98a) 1, 2 and 3
99b) 1 and 2
100c) 3 and 4
101d) 2, 3 and 4
10219. Flexible manufacturing systems (FMS) are reported to have a number of benefits. Which is NOT a reported benefit of FMS?
103a) Lead time and throughput time reduction
104b) Increased quality
105c) More flexible than the manufacturing systems they replace
106d) Increased utilisation
10720. Which materials-processing technology gives the advantage of precision, accuracy and optimum use of cutting tools, which maximise their life and higher labour productivity?
1086
109a) Industrial robots
110b) Flexible manufacturing systems (FMS)
111c) Computer-integrated manufacturing (CIM)
112d) NC (and CNC) machine tools
1137
114CAD CAM
1151. When absolute tool positioning is used, ____.
116a) a mistake in dimensioning an individual point does not affect remaining dimensions
117b) all tool movement is measured from a fixed point or origin
118c) it is easier to check for errors
119d) All the answers
1202. A straight-cut system ____.
121a) permits controlled tool travel along one axis at a time
122b) is used for operations performed at a fixed location in terms of a two-axis coordinate position
123c) precisely controls machine and tool movement at all times and in all planes
124d) permits controlled tool travel along three axis at a time
1253. A point-to-point NC movement system ____.
126a) is typically used for drilling, punching, and spot welding.
127b) is used for operations at a fixed location in terms of a two-axis coordinate position
128c) tool movement from one position to the next does not have to follow a specific path
129d) All of the answers
1304. With contour or continuous path NC movement system, ____.
131a) cutter size and other variables must be considered when the program is prepared
132b) cutter location is monitored continuously
133c) cutting is continuous and can be in six axes simultaneously
134d) All of the answers
1358
1365. In a typical manufacturing environment, CAD modeling finds its role in:
137a) Design
138b) Drafting
139c) Manufacturing
140d) All of the answers
1416. The method which used either delta x or delta y, whichever is larger, is chosen as one raster unit to draw the line -the algorithm is called?
142a) Bresenham’s Line Algorithm
143b) DDA Line Algorithm
144c) Mid point Line Algorithm
145d) All of the answers
1467. Which of the following is not an object-space hidden surface removal algorithm
147a) Back-Face Culling
148b) Depth Buffer
149c) Painter’s Algorithm
150d) FFTW Line Algorithm
1518. In a CAD package, mirror image of a 2D point P (5, 10) is to be obtained about a line which passes through the origin and makes an angle of 45° counterclockwise with the X-axis. The coordinates of the transformed point will be
152a) (7.5, 5)
153b) (10, 5)
154c) (7.5, -5)
155d) (10, -5)
1569
1579. Which of the following hidden surface removal algorithms potentially causes a bottleneck in the Graphics Pipeline?
158a) Back-Face Culling
159b) Depth Buffer
160c) Painter’s Algorithm
161d) All of the answers
16210. For the following question, consider the line which starts at location (5, 14) and ends at position (21, 2).How many pixels will there be in this line?
163a) 12
164b) 16
165c) 20
166d) 24
16711. For the following question, consider the line which starts at location (5, 14) and ends at position (21, 2).Which is the primary direction?
168a) X
169b) Y
170c) Z
171d) All of the answers
17212. With the DDA algorithm, what will be the amount (amt in notes) added to the secondary component each time through the loop
173a) 1/2
174b) -3/4
175c) 3/4
176d) -4/3
17710
17813. The computerized technology that is used to design parts is known as:
179a) CIM
180b) CAD
181c) CAM
182d) All of the answers
18314. IGES stands for
184a) Initial Graphics Exchange System
185b) Initial Graphics Exchange Software
186c) Initial Graphic Exchange Solution
187d) Initial Graphics Exchange Specification
18815. Group technology and CAPP are the activities of
189a) Computer Aided Engineering
190b) Computer Aided Manufacturing
191c) Computer Integrated Manufacturing
192d) Flexible manufacturing
19316. Computer Integrated Manufacturing deals with
194a) Design and business functions
195b) Design activities only
196c) Design, Manufacturing and business functions
197d) Manufacturing and business functions
19817. B-Rep is a methods of ____________
199a) Solid modeling
200b) Surface modeling
20111
202c) Wire frame modeling
203d) 2D modeling
20418. A system permitting the manufacture of large quantities of identical goods using repetitive actions by people or machines is called:
205a) manufacturing.
206b) operations.
207c) mass production.
208d) assembly line.
20919. An approach that tries to match the output of manufacturing with market demand, in order to minimize inventories is called:
210a) JIT.
211b) MRP.
212c) CAD.
213d) CAM.
21420. In which of the following machining manual part programming is done?
215a) CNC machining
216b) NC machining
217c) DNC machining
218d) FMS machining
21921. The tool of an NC machine has to move along a circular arc from (5, 5) to (10,10) whileperforming an operation. The centre of the arc is at (10, 5). Which one of the following NC tool path commands performs the above mentioned operation?
220a) N010G02 X10 Y10 X5 Y5 R5
221b) N010G03 X10 Y10 X5 Y5 R5
22212
223c) N010G01 X5 Y5 X10 Y10 R5
224d) N010G02 X5 Y5 X10 Y10 R5
22522. What are the main components of an NC machine?
2261. Part program 2. Machine Control Unit 3. Servo meter
227Select the correct answer using the code given below:
228a) 1, 2 and 3
229b) 1 and 2 only
230c) 2 and 3 only
231d) 1 and 3 only
23223. Which of the following are the rules of programming NC machine tools in APT language?
2331. only capital letters are used 2. A period is placed at the end of each statement 3. Insertion of space does not affect the APT word
234Select the correct answer using the codes given below:
235a) 1 and 2
236b) 2 and 3
237c) 1and 3
238d) 1 alone
23924. Which of the following are valid statements for point to point motion of the tool in APT language?
2401. GOTO/............ 2. GO DLTA/............ 3. GO/TO, ……….
241Select the correct answer using the codes given below:
242a) 1 and 2
243b) 2 and 3
244c) 1 and 3
24513
246d) 1, 2 and 3
24725. In APT language, the cutter motion in incremental coordinate mode is addressed as
248a) GO/TO/.....
249b) GO/TO.....
250c) GO DLTA/....
251d) GO FWD/ ...
25226. In an NC machining operation, the tool has to be moved from point (5, 4) to point (7, 2) along a circular path with centre at (5, 2). Before starting the operation, the tool is at (5, 4). The correct G and M code for this motion is
253a) N010 G03 X7.0 Y2.0 I5.0 J2.0
254b) N010 G02 X7.0 Y2.0 I5.0 J2.0
255c) N010 G01 X7.0 Y2.0 I5.0 J2.0
256d) N010 G00 X7.0 Y2.0 I5.0 J2.0
25727. In a point to point control NC machine, the slides are positioned by an integrally mounted stepper motor drive. If the specification of the motor is 1degree/pulse, and the pitch of the lead screw is 3.6 mm, what is the expected positioning accuracy?
258a) 1μm
259b) 10μm
260c) 50μm
261d) 100μm
26228. In a point-to-point type of NC system
263a) control of position and velocity of the tool is essential
264b) control of only position of the tool is sufficient
265c) control of only velocity of the tool is sufficient
26614
267d) neither position nor velocity need be controlled
26829. A 'block' of information in N.C. machine program means
269a) one row on tape
270b) a word comprising several rows on tape
271c) one complete instruction
272d) one complete program for a job
27330. In a CNC machine tool, encoder is used to sense and control
274a) spindle position
275b) table velocity
276c) spindle speed
277d) coolant flow
27831. Interpolation in the controller refers to control of which one of the following in a CNC machine?
279a) Loading/unloading of jobs on machine
280b) Loading/unloading of tools from the tool changer
281c) Axes of machine for contouring
282d) Coolant and miscellaneous functions on machine
28332. Feed drives in CNC milling machines are provided by
284a) synchronous motors
285b) induction motors
286c) stepper motors
287d) servo-motors.
28815
28933. Which type of motor is NOT used in axis or spindle drives of CNC machine tools?
290a) induction motor
291b) dc servo motor
292c) stepper motor
293d) linear servo motor
29434. During the execution of a CNC part program block NO20 G02 X45.0 Y25.0 R5.0 the type of tool motion will be
295a) circular Interpolation – clockwise
296b) circular Interpolation - counter clockwise
297c) linear Interpolation
298d) rapid feed
29935. In finish machining of an island on a casting with CNC milling machine, an end mill with 10mm diameter is employed. The corner points of the island are represented by (0, 0), (0, 30), (50,30), and (50, 0). By applying cutter radius right compensation, the trajectory of the cutter will be
300a) (-5, 0), (-5, 35), (55, 35), (55, -5), (-5, -5)
301b) (0, -5), (55, -5), (55, 35), (-5, 35), (-5, -5)
302c) (5, 5), (5, 25), (45, 25), (45, 5), (5, 5)
303d) (5, 5), (45, 5), (45, 25), (5, 25), (5, 5)
30436. Flexible manufacturing allows for:
305a) tool design and production
306b) automated design
307c) quick and inexpensive product change
308d) quality control
30916
31037. Consider the following characteristics:
3111. Single machine tool 2. Manual materials handling system 3. Computer control 4. Random sequencing of parts to machines
312Which of the above characteristics are associated with flexible manufacturing system?
313a) 1, 2 and 3
314b) 1 and 2
315c) 3 and 4
316d) 2, 3 and 4
31738. In which machining system, the highest level of automation is found?
318a) CNC machine tools
319b) Automatic transfer machines
320c) Machine tools with electro-hydraulic positioning and control
321d) DNC machining system
32239. Which one of the following is the third basic component of robots besides power supply and control (memory) console?
323a) Software
324b) Coaxial cable
325c) Mechanical unit arm
326d) Microcomputer
32740. Flexible manufacturing systems (FMS) are reported to have a number of benefits. Which is NOT a reported benefit of FMS?
328a) Lead time and throughput time reduction
329b) Increased quality
330c) More flexible than the manufacturing systems they replace
331d) Increased utilisation
33217
33341. Which materials-processing technology gives the advantage of precision, accuracy and optimum use of cutting tools, which maximise their life and higher labour productivity?
334a) Industrial robots
335b) Flexible manufacturing systems (FMS)
336c) Computer-integrated manufacturing (CIM)
337d) NC (and CNC) machine tools
33842. What do Flexible Manufacturing systems (FMS) do?
339a) Moves and manipulates products, parts or tolls
340b) Co-ordinates the whole process of manufacturing and manufactures a part, component or product
341c) Moves materials between operations
342d) Completely manufactures a range of components without significant human intervention during the processing
34343. Technology that is peripheral to the actual creation of goods and services is sometimes called:
344a) Direct process technology
345b) Indirect process technology
346c) Focused process technology
347d) Complementary process technology
34844. Which of the following is not true of computer numerically controlled (CNC) machines?
349a) They can ‘learn’ from process errors.
350b) They can eliminate operator error.
351c) They can give better productivity to the process.
352d) They give more accuracy and precision to the process.
35318
35445. What is the name of a system which brings together several technologies into a coherent system?
355a) Focused integration systems
356b) Portable manufacturing systems
357c) Flexible manufacturing systems
358d) Automated integration systems
35946. Which of the following process technologies is associated with low volume and high variety?
360a) Flexible manufacturing systems
361b) Dedicated systems
362c) Flexible transfer lines
363d) Computer numerically controlled machines
36447. The use of Internet-based technology, either to support existing business processes or to create entirely new business opportunities, has become known as what?
365a) E-process management
366b) E-business
367c) E-globalisation
368d) E-value creation
36948. Which type of model is likely to be created with a rapid prototyping system?
370a) Mathematical model
371b) Wireframe model
372c) Surface model
373d) Scale model
37419
37549. An industrial robot's end effector can be changed to perform different tasks, including which of the following?
376a) Spot welding
377b) Materials handling
378c) Spray painting
379d) All of the answers
38050. By using CIM to control all phases of manufacturing, firms hope to reap what benefits?
381a) Increased productivity
382b) Improved quality
383c) Enhanced flexibility
384d) All of the answer
385CAD/CAM
3861. Each screen point is referred to as .........................
387a) Resolution
388b) Pixel
389c) Persistence
390d) Dot Pitch
3912. The distance from one pixel to the next pixel is called ...........
392a) Resolution
393b) Random scan
39420
395c) Pixmap
396d) Dot Pitch
3973. The region code of a point within the window is ............
398a) 1111
399b) 0000
400c) 1000
401d) 0001
4024. Which of the following line algorithms used integer only arithmetic to rasterize lines?
403a) Bresenham’s Line Algorithm
404b) DDA Line Algorithm
405c) FFTW Line Algorithm
406d) All the answer
4075. Which of the following hidden surface removal algorithms potentially causes a bottleneck in the Graphics Pipeline?
408a) Back-Face Culling
409b) Depth Buffer
410c) Painter’s Algorithm
411d) All the answer
4126. Higher persistence phosphorus needs _________ refresh rate.
413a) Lower
414b) Higher
415c) Medium
416d) None of these
41721
4187. The purpose of refreshing a CRT is ..........................
419a) To avoid flickering
420b) To maintain steady picture
421c) To avoid fading of pixels
422d) All the answer
4238. The rectangle portion of the interface window that defines where the image will actually appear are called
424a) Transformation viewing
425b) View port
426c) Clipping window
427d) Screen coordinate system
4289. Which of the following is not an object-space hidden surface removal algorithm?
429a) Back-Face Culling
430b) Depth Buffer
431c) Painter’s Algorithm
432d) All the answer
43310. The .............. combines the volumes occupied by overlapping 3D objects using set operations
434a) Beam penetration
435b) CSG Method
436c) Sweep representation
437d) All the answer
43811. In CRT, the electron intensity is adjusted using .................
43922
440a) Accelerating anode
441b) Control grid
442c) Electron gun
443d) Focusing anode
44412. Memory area holding the intensity information of an image is called ..............
445a) Refresh buffer
446b) Font cache
447c) Picture definition
448d) Video controller
44913. Identify the odd one out from the following
450a) Vector display
451b) Raster scan display
452c) Calligraphic display
453d) Stroke-writing display
45414. Identify different type of computer graphics
455a) Monochrome and Color
456b) CRT and Flat panel
457c) Vector and Raster
458d) Monitors and Hardcopy devices
45915. A bitmap is .............. bit(s) per pixels
460a) 0
461b) 1
462c) 2
46323
464d) 3
46516. The basic transformations include
466a) Translation
467b) Rotation
468c) Scaling
469d) All the answer
47017. The transformation in which an object is moved in a minimum distance path from one position to another is called
471a) Rotation
472b) Replacement
473c) Translation
474d) Scaling
47518. The transformation in which an object is moved from one position to another in circular path around a specified pivot point is called
476a) Rotation
477b) Shearing
478c) Translation
479d) Scaling
48019. The transformation that produces a parallel mirror image of an object are called
481a) Rotation
482b) Reflection
483c) Translation
484d) Scaling
48524
48620. Forming products of transformation matrices is often referred as
487a) Concatenation
488b) Composition
489c) both a&b
490d) only a
49121. The .............. combines the volumes occupied by overlapping 3D objects using set operations
492a) CSG method
493b) B-rep method
494c) Sweep representation
495d) All the answer
49622. ................... is created by revolution of a circle about an axis lying in its plane.
497a) Sphere
498b) Ellipsoid
499c) Torus
500d) Cylinder
50123. The point about which an object is rotated is called ...................
502a) Fixed point
503b) Central point
504c) Pivot point
505d) None
50624. A surface of revolution is generated by a .................. of a 2D curve.
507a) Translational sweep
50825
509b) Rotational sweep
510c) union
511d) intersection
51225. Identify line clipping algorithms from the following
513a) Cohen- Sutherland algorithm
514b) Liang-Barsky clipping
515c) Nicholl-Lee-Nicholl clipping
516d) All the answer
51726. The transformation in which the dimension of an object are changed relative to a specified fixed point is called
518a) Rotation
519b) Reflection
520c) Translation
521d) Scaling
52227. The amount of light emitted by the phosphor coating depends on the?
523a) Number of electrons striking the screen
524b) Speed of electrons striking the screen
525c) Distance from the cathode to the screen
526d) phosphor coating thickness
52728. ........ used to regulate the flow of elections in CRT ?
528a) Electron gun
529b) Focusing anode
530c) Control grid
53126
532d) All the answer
53329. The refresh rate below which a picture flicker is ................
534a) 25
535b) 30
536c) 26
537d) 50
53830. The maximum number of points that can be displayed without overlap on a CRT
539a) Aspect Ratio
540b) Resolution
541c) Brightness
542d) Pixel
543Computer Aided Machine Drawing
5441. If a client of yours is having difficulty visualizing a design, what type of drawing would be the easiest to understand?
545a) Axonometric
546b) three-view orthographic
547c) one-view orthographic
548d) bimetric
5492. Which of the following is not a pictorial drawing?
550a) isometric
551b) multiview
55227
553c) perspective
554d) axonometric
5553. Which of the following projection methods does not use projectors perpendicular to the projection plane?
556a) isometric
557b) orthographic
558c) oblique
559d) axonometric
5604. A circle will appear on an isometric drawing as a(n) __________ .
561a) ellipse
562b) cycloid
563c) circle
564d) parabola
5655. An axonometric drawing which has two axes divided by equal angles is:
566a) dimetric
567b) trimetric
568c) orthographic
569d) isometric
5706. An axonometric drawing which has all three axes divided by equal angles is:
571a) bimetric
572b) trimetric
573c) orthographic
574d) isometric
57528
5767. In a trimetric drawing, the relationship of the angle between axes to each other is:
577a) three are equal
578b) two are equal
579c) three are unequal
580d) none of the answers
5818. In an isometric sketch of a cube:
582a) the frontal face appears in its true shape
583b) the receding axes are at 45 degrees to the horizontal
584c) all faces are equally distorted
585d) only the depth distances must be reduced
5869. In isometric drawings:
587a) Two axes are perpendicular
588b) True measurements can be made only along or parallel to the isometric axes
589c) All faces are unequally distorted
590d) None of the answers
59110. In an axonometric drawing, the projection rays are drawn _________ to each other and _______ to the plane of projection.
592a) parallel.....oblique
593b) oblique.....parallel
594c) parallel.....perpendicular
595d) parallel....parallel
59611. One method of drawing an ellipse that represents an isometric pictorial circle is known as:
59729
598a) the box construction method
599b) the coordinate construction method
600c) the four-center approximation method
601d) the offset construction method
60212. Non-isometric lines are located and sketched how?
603a) They are drawn parallel to the isometric axis.
604b) They are measured using the angle from the multiview.
605c) They are measured using a non-isometric template.
606d) They are located by determining the endpoints of the non-isometric line.
60713. In an oblique sketch of a cube:
608a) the frontal face appears in its true shape
609b) both receding axes are at 30 degrees to the horizontal
610c) all faces are equally distorted
611d) the depth distances must be reduced
61214. In an oblique drawing, all of the following angles are commonly used for drawing the depth axis, except:
613a) 30°
614b) 45°
615c) 60°
616d) 90°
61715. All of the following are processes (as opposed to input or output) in a manufacturing business except:
618a) Material
619b) Planning
62030
621c) Documenting
622d) Designing
62316. following operations can make use of the CAD database, except:
624a) Designing
625b) Marketing
626c) Producing
627d) None of the answers
62817. What type of sketches are typically used in the refinement stage of the design process?
629a) isometric
630b) document
631c) oblique
632d) ideation
63318. What type of sketch incorporates convergence?
634a) isometric
635b) perspective
636c) oblique
637d) multiview
63819. What type of sketch shows the front in true shape?
639a) isometric
640b) perspective
641c) oblique
642d) axonometric
64331
64420. What is the major difference(s) between perspective and parallel projection?
645a) Parallel projection can only be used with objects containing parallel edges.
646b) Perspective projection gives a more realistic representation of an object.
647c) Parallel projection is equivalent to a perspective projection where the viewer is standing infinitely far away.
648d) Perspective projection and Parallel projection where the viewer is standing infinitely far away gives a more realistic representation of an object.
64921. Which statement(s) is true about the precedence of lines?
650a) a hidden line has precedence over a center line
651b) a center line has precedence over a visible line
652c) a visible line has precedence over a miter line
653d) all of the answers
65422. Which of the following is typically represented in a drawing but does not have a true physical counterpart on the object?
655a) edge of planar surface
656b) edge of a circular face
657c) corner of a rectangle
658d) limiting element of a curved surface
65923. A cutting plane normal to a face of a cube has to be ___________ in order to cut an oblique face.
660a) rotated about one axis
661b) rotated about one axis and translated
662c) rotated about two axes
663d) rotated about two axes and translated
66432
66524. The difference between the removed and revolved sections is
666a) the view in both sections is shown on the same view
667b) the view in both sections is made seperatly
668c) in removed section a view is made outside in main view but incase of revolved,the view is made in between the main view
669d) none of the answers
67025. The difference between Full and Half section is as follows
671a) In full section quarter portion is removed and in half section half portion is removed
672b) In half section quarter portion is removed and in quarter section half portion is removed
673c) all the answers
674d) none of the answers
67526. the hatching between two meshing surfaces is
676a) in the same direction
677b) in the opposite direction
678c) not specified
679d) all the answers
68027. which statement is true for a cutting plane
681a) it is always a straight line
682b) its axis depends on shape of the object
683c) it is always in the centre of the object
684d) it makes an angle with the object axis
68528. broken outsection is used to show
68633
687a) external and internal details for entire length
688b) very long object
689c) external and internal details for a portion of length
690d) small objects shown broken
69129. Hacthing means
692a) lines at regular interval
693b) repeated pattern at regular interval
694c) repeated pattern at regular interval in a boundary
695d) solid filledup area
69630. pattern to be used for sectioning of Cast iron
697a) ANSI 31
698b) ANSI 32
699c) ANSI 33
700d) ANSI 34
70131. Value of an angle equal to zero for ANSI 31 pattern will draw lines at
702a) 0 degrees
703b) 45 degrees
704c) 90 degrees
705d) 135 degrees
70632. Auxiliary view is drawn to show
707a) an inclined surface
708b) complicated surfaces
709c) actual shape of surface which otherwise is illusive
71034
711d) big parts
71233. A skew surface is
713a) twisted
714b) bent and twisted
715c) inclined to any two orthogonal planes
716d) inclined to all principal planes
71734. Auxiliarey view is drawn
718a) opposite to front view
719b) parallel to inclined plane
720c) opposite to tpo view
721d) on the other side of side view
72235. Command to draw conveniently many construction lines at a specified angle is
723a) XLINE
724b) LINE
725c) PARLINE
726d) ALINE
72736. Side view of a threaded member is drawn as
728a) semi-circle
729b) full circle
730c) three quarter circle
731d) slightly more than three quarter circle
73237. types of threads used on a pipe are
73335
734a) tapered
735b) parallel
736c) square
737d) knukle
73838. A typical set of mechanical drawing includes
739a) exploded assembly
740b) part details
741c) parts list
742d) all the answers
74339. The angle between flamks of a metric thread is
744a) 60 degrees
745b) 90 degrees
746c) 75 degrees
747d) 55 degrees
74840. In isometric projection the three edges of an object are inclined to eachother at
749a) 60 degrees
750b) 120 degrees
751c) 100 degrees
752d) 90 degrees
75341. the number of cotters used in an assembly of cotter and sleeve joint are
754a) 1
755b) 5
756c) 4
75736
758d) 2
75942. A square lamina in isometric projection appears as
760a) rhombus
761b) rectangle
762c) trapezium
763d) parallelogram
76443. Which one among the following represents a permanant fastner
765a) Nut
766b) Rivet
767c) Screw
768d) Bolt
76944. the convexity provided on the rim of the solid web cast iron is called
770a) Bending
771b) Curving
772c) Crowning
773d) Riveting
77445. The isometric view of a sphere is always
775a) a circle
776b) an ellipse
777c) a parabola
778d) a semicircle
77946. In isometric method the four center method is used to construct
78037
781a) an ellipse
782b) a square
783c) a rectangle
784d) a triangle
78547. A foot step bearing is a
786a) journal bearing
787b) thrust bearing
788c) pivot bearing
789d) pedestal bearing
79048. The profile of gear teeth is in the form of
791a) parabola
792b) involute
793c) spiral
794d) helix
79549. The curve generated by a point on the circumference of a circle,which rolls without slipping along outside of another circle is
796a) Hypocycloid
797b) epicycloid
798c) cycloid
799d) trochoid
80050. If an object lies in the third quardant , its position with respect to reference planes will be
801a) infront of V.P,above H.P
802b) behind V.P,above H.P
80338
804c) behind V.P,below H.P
805d) infront of V.P,below H.P
806Computer Aided Machine Drawing
8071. The Press-Pull tool will ________ the face of a solid model in the direction it faces.
808a) taper
809b) extrude
810c) spiral
811d) circular
8122. The MASSPROP shortcut will provide the following information
813a) mass
814b) volume
815c) bounding box
816d) all the answers
8173. CAD programs which incorporate parametric modeling utilize a system in which the dimensions control the ________.
818a) size and shape of the model features
819b) perspective of the model
820c) shading used to render the model
821d) colouring
8224. The Conceptual Visual Style tool is located on the ________ toolbar.
823a) Visual Styles
824b) Modify
82539
826c) 3D-Modelling
827d) optimize
8285. The default position of the UCS icon is positioned at ________ on the AutoCAD grid.
829a) 0,0,0
830b) 10,10,10
831c) 20,20,20
832d) -10,-10,-10
8336. In perspective drawings this is placed between the observer and the object:
834a) Vanishing point / horizon
835b) station point
836c) ground line
837d) Plane of projection / picture plane
8387. If a designer is developing a plan for a project in which the entire part is made out of ¾" thick plywood and he only wants to use one view, he should use the ________ view.
839a) front
840b) top
841c) right
842d) back
8438. Architectural drawings used to construct a house are often plotted with a scale of ¼" = 1'-0". What scale is this?
844a) Quarter
845b) Half
846c) Full
847d) Double
84840
8499. In multi-view drawing it is common practice to include three views, the front, the top and the right side. If no dimensions are required on the right side view the drafter can ________.
850a) leave the view as is
851b) eliminate the view
852c) use the left view instead
853d) none of the answers
85410. A full scale technical drawing will have a scale factor of ________.
855a) 1:1
856b) 1:2
857c) 2:1
858d) 1:4
85911. Hidden lines are drawn as
860a) dashed narrow lines
861b) dashed wide lines
862c) long-dashed dotted wide line
863d) long-dashed diuble dotted wide line
86412. Which type of line is part of a dimension?
865a) break lines
866b) phantom lines
867c) extension lines
868d) cutting plane lines
86913. Which of the following operating systems is used with CAD systems?
87041
871a) DOS
872b) UNIX
873c) LINUX
874d) all the answers
87514. What type of sketches are typically used in the refinement stage of the design process?
876a) isometric
877b) document
878c) oblique
879d) ideation
88015. This allows the performance of structures to be analyzed and tested efficiently, accurately, and quickly:
881a) Computer-aided manufacturing
882b) computer-aided designm
883c) computer-aided engineering
884d) computer-aided prototyping
88516. Automation means
886a) increase productivity
887b) workers controlling machines
888c) assisting and replacing humanes by machines
889d) all the answers
89017. the main function of CAD is
891a) Documentation
892b) Manufacturing
89342
894c) curing
895d) marketing
89618. the ultimate solution for the computer aided design and manufacturing problem will be
897a) LANs
898b) the microprocessor
899c) turnkey systems
900d) development of a more efficient display controller
90119. robots are specified by
902a) control system
903b) axis of movement
904c) payload
905d) all the answers
90620. the advantage of implementing CAD is to
907a) increase quality of design
908b) expertise in the area of data base manufacturing management
909c) increase productivity
910d) improve communication
911Design of machine elements
9121. A 60 mm long and 6 mm thick fillet weld carries a steady load of 15 kN along the weld. The shear strength of the weld material is equal to 200 MPa. The factor of safety is
91343
914a) 2.4
915b) 3.4
916c) 4.8
917d) 6.8
9182. A threaded nut of M16, ISO metric type, having 2 mm pitch with a pitch diameter of 14.701 mm is to be checked for its pitch diameter using two or three numbers of balls or rollers of the following sizes
919a) Rollers of 2 mm φ
920b) Balls of 2 mm φ
921c) Rollers of 1.155 mm φ
922d) Balls of 1.155 mm φ
9233. Square key of side "d/4" each and length l is used to transmit torque "T" from the shaft of diameter "d" to the hub of a pulley. Assuming the length of the key to be equal to the thickness of the pulley, the average shear stress developed in the key is given by
924a) 4T/ ld
925b) 16 T/ ld 2
926c) 8T / ld 2
927d) 16 T / πd 3
9284. A key connecting a flange coupling to a shaft is likely to fail in
929a) Shear
930b) Tension
931c) Torsion
932d) Bending
9335. The S-N curve for steel becomes asymptotic nearly at
93444
935a) 10 3 cycles
936b) 10 4 cycles
937c) 10 6 cycles
938d) 10 9 cycles
9396. A cylindrical shaft is subjected to an alternating stress of 100 MPa. Fatigue strength to sustain 1000 cycles is 490 MPa. If the corrected endurance strength is 70 MPa, estimated shaft life will be
940a) 1071 cycles
941b) 15000 cycles
942c) 281914 cycles
943d) 928643 cycles
9447. A forged steel link with uniform diameter of 30 mm at the centre is subjected to an axial force that varies from 40 kN in compression to 160 kN in tension. The tensile (Su), yield (Sy,) and corrected endurance (Se) strength of the steel material are 600 MPa, 420 MPa and 240 MPa respectively. The factor of safety against fatigue endurance as per Soderberg’s criterion is
945a) 1.26
946b) 1.37
947c) 1.45
948d) 2.00
9498. The yield strength of a steel shaft is twice its endurance limit. Which of the following torque fluctuation represent the most critical situationaccording to Soderberg criterion?
950a) -T/2 to +T
951b) -T to +T
952c) 0 to +T
953d) +T/2 to +T
95445
9559. A thin supercritical pressure vessel of 200 mm diameter and 1 mm thickness is subjected to an internal pressure varying from 4 to 8 MPa. Assume that the yield, ultimate, and endurance strength of material are 600, 800 and 400 MPa respectively. The factor of safety as per Goodman’s relation is
956a) 2.0
957b) 1.6
958c) 1.4
959d) 1.2
96010. A large uniform plate containing a rivet-hole is subjected to uniform uniaxial tension of 95 MPa. width of the plate 10 cm and diameter of the hole =5 mm.The maximum stress in the plate is
961a) 100 MPa
962b) 190 Mpa
963c) 285 Mpa
964d) None of the answers
965DESIGN OF MACHINE ELEMENTS
9661. A special case of ductility which permits materials to be rolled or hammered into thin sheets, is called
967a) plasticity
968b) elasticity
969c) ductility
970d) malleability
9712. The material commonly used for crane hooks is
972a) cast iron
973b) wrought iron
974c) mild steel
97546
976d) aluminium
9773. The effect of key ways on a shaft is to reduce its load carrying capacity and to increase its torsional rigidity.
978a) True
979b) False
9804. The efficiency of a riveted joint is equal to
981a) Pt/P
982b) Ps/P
983c) Pc/P
984d) least of Pt, Ps and Pc/P
9855. Which of the following welded joint is designed for shear strength ?
986a) Transverse fillet welded joint
987b) Parallel fillet welded joint
988c) Butt welded joint
989d) all of these
9906.
991In designing a connecting rod, it is considered like __________ for buckling about X-axis.
992a) both ends hinged
993b) both ends fixed
994c) one end fixed and the other end hinged
995d) one end fixed and the other end free
99647
9977. The sleeve or muff coupling is designed as a
998a) dun cylinder
999b) thick cylinder
1000c) solid shaft
1001d) hollow shaft
10028. Screws used for power transmission should have
1003a) Low efficiency
1004b) high efficiency
1005c) very fine threads
1006d) strong teeth
10079. The toughness of a material __________ when it is heated.
1008a) increases
1009b) decreases
1010c) does not change
101110. The number of slots in a 25 mm castle nut is
1012a) 2
1013b) 4
1014c) 6
1015d) 8
101611. A screw is said to be over hauling screw, if its efficiency is
1017a) less than 50%
1018b) more than 50%
1019c) equal to 50%
102048
1021d) none of these
102212. Soderberg relation is based on __________ of the material whereas all other failure relation for dynamic loading are based on ultimate strength of the material.
1023a) elastic strength
1024b) yield strength
1025c) shear strength
102613. In a flange coupling, the flanges are coupled together by means of
1027a) bolts and nuts
1028b) studs
1029c) headless taper bolts
1030d) none of these
103114. A transmission shaft includes
1032a) counter shaft
1033b) line shaft
1034c) over head shaft
1035d) all of these
103615. A locking device in which the bottom cylindrical portion is recessed to receive the tip of the locking set screw, is called
1037a) castle nut
1038b) jam nut
1039c) ring nut
1040d) sawn nut
104116. Slenderness ratio is the ratio of
104249
1043a) maximum size of column to minimum size of column
1044b) width of column to depth of column
1045c) effective length of column to least radius of gyration of the column
1046d) effective length of column to width of column
104717. A crankshaft is a __________ shaft.
1048a) transmission
1049b) machine
105018. According to Unwin's formula, the relation between the diameter of rivet hole (d) and the thickness of plate (t) is given by (where d and t are in mm)
1051a) d = t
1052b) d = 1.6 t
1053c) d = 2 t
1054d) d = 6 t
105519. In order to avoid tearing of the plate at an edge, the distance from the centre line of the rivet hole to the nearest edge of the plate should be equal to (where d = Diameter of rivet hole)
1056a) d
1057b) 1.5 d
1058c) 2 d
1059d) 2.5 d
106020. The value of stress concentration factor depends upon
1061a) material of the part
1062b) geometry of the part
1063c) material and geometry of the part
106450
1065d) none of these
106621. Which of the following material has the maximum ductility?
1067a) Mild steel
1068b) Copper
1069c) Zinc
1070d) Aluminium
107122. When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at the
1072a) head
1073b) shank
1074c) thread
1075d) middle
107623. In order to obtain the bolts of uniform strength, an axial hole is drilled through the head as far as the threaded portion such that the area of shank becomes equal to the root area of the thread.
1077a) True
1078b) False
107924. An open belt drive is used when
1080a) shafts are arranged parallel and rotate in the opposite directions
1081b) shafts are arranged parallel and rotate in the same directions
1082c) shafts are arranged at right angles and rotate in one definite direction
1083d) driven shaft is to be started or stopped whenever desired without interferring with the driving shaft
108451
108525. The pipe joint mostly used for pipes carrying water at low pressures is
1086a) socket joint
1087b) nipple joint
1088c) union joint
1089d) spigot and socket joint
109026. According to Guest's theory, the failure occurs at a point in a member when the maximum shear stress in a bi-axial stress system reaches the shear stress at elastic limit in simple tension test.
1091a) True
1092b) False
109327. A flanged pipe joint will be a leak-proof joint, if the circumferential pitch of the bolts is (where d = Diameter of bolt hole)
1094a) less than 20 d
1095b) greater than 30 d
1096c) between 20 d and 30 d
1097d) equal to inside diameter of pipe
109828. Stress concentration is caused due to
1099a) variations in load acting on a member
1100b) variations in properties of materials in a member
1101c) abrupt change of cross-section
1102d) all of these
110329. The resistance to fatigue of a material is measured by
1104a) elastic limit
1105b) Young's modulus
110652
1107c) ultimate tensile strength
1108d) endurance limit
110930. Two shafts A and B under pure torsion are of identical length and identical weight and are made of the same material. The shaft A is solid and the shaft B is hollow. We can say that
1110a) shaft B is better than shaft A
1111b) shaft A is better than shaft B
1112c) both the shafts are equally good
111331. In a flange coupling, the thickness of flanges is taken as one-half the diameter of shaft.
1114a) Agree
1115b) Disagree
111632. Which of the following property is desirable in parts subjected to shock and impact loads?
1117a) Strength
1118b) Stiffness
1119c) Brittleness
1120d) Toughness
112133. Oldham coupling is used to transmit power between two parallel shafts which are slightly offset.
1122a) True
1123b) False
112434. A shaft is subjected to fluctuating loads for which the normal torque (T) and bending moment (M) are 1000 N-m and 500 N-m respectively. If the combined shock and fatigue factor for bending is 1.5 and combined shock and fatigue factor for torsion is 2, then the equivalent twisting moment for the shaft is
1125a) 2000 N-m
112653
1127b) 2050 N-m
1128c) 2100 N-m
1129d) 2136 N-m
113035. When a machine member is subjected to torsion, the torsional shear stress set up in the member is
1131a) zero at both the centroidal axis and outer surface of the member
1132b) maximum at both the centroidal axis and outer surface of the member
1133c) zero at the centroidal axis and maximum at the outer surface of the member
1134d) maximum at the centroidal axis and zero at the outer surface of the member
113536. A screw is specified by its
1136a) major diameter
1137b) minor diameter
1138c) pitch diameter
1139d) pitch
114037. Stress concentration factor is defined as the ratio of
1141a) maximum stress to the endurance limit
1142b) nominal stress to the enurance limit
1143c) maximum stress to the nominal stress
1144d) nominal stress to the maximum stress
114538. The eye bolts are used for
1146a) transmission of power
1147b) locking devices
1148c) lifting and transporting heavy machines
114954
1150d) absorbing shocks and vibrations
115139. The endurance or fatigue limit is defined as the maximum value of the stress which a polished standard specimen can withstand without failure, for infinite number of cycles, when subjected to
1152a) static load
1153b) dynamic load
1154c) static as well as dynamic load
1155d) completely reversed load
115640. According to Rankine's theory, the failure occurs at a point in a member
1157a) when the maximum shear stress in a bi-axial stress system reaches the shear stress at elastic limit in a simple tension test
1158b) when the maximum principal stress in a bi-axial stress system reaches the elastic limit of the material in a simple tension test
1159c) when the strain energy per unit volume in a bi-axial stress system reaches the strain energy at the elastic limit per unit volume as determined from a simple tension test
1160d) when the maximum principal strain in a bi-axial stress system reaches the strain at the elastic limit as determined from a simple tension test
116141. In a steam engine, the valve rod is connected to an eccentric rod by means of
1162a) cotter joint
1163b) knuckle joint
1164c) universal joint
1165d) flange coupling
116642. Which of the following formula is used in designing a connecting rod ?
1167a) Euler's formula
1168b) Rankine's formula
116955
1170c) Johnson's straight line formula
1171d) Johnson's parabolic formula
117243. When a material is subjected to fatigue loading, the ratio of the endurance limit to the ultimate tensile strength is
1173a) 0.20
1174b) 0.35
1175c) 0.50
1176d) 0.65
117744. A flange coupling is a type of rigid coupling.
1178a) Correct
1179b) Incorrect
118045. The strength of the un-riveted plate (P) per pitch length is equal to
1181a) p.d.σt
1182b) p.t.σt
1183c) (p - d)σt
1184d) (p - d)tσt
118546. Two shafts of the same length and material are joined in series. If the ratio of their diameters is 2, then the ratio of their angles of twist will be
1186a) 2
1187b) 4
1188c) 8
1189d) 16
119047. Wahl's stress factor __________ very rapidly as the spring index decreases.
119156
1192a) increases
1193b) decreases
119448. For circumferential joint in boilers, the type of joint used is
1195a) butt joint with single cover plate
1196b) butt joint with double cover plate
1197c) lap joint with one ring overlapping the other
1198d) any one of the above
119949. In cyclic loading, stress concentration is more serious in
1200a) brittle materials
1201b) ductile materials
1202c) brittle as well as ductile materials
1203d) elastic materials
120450. For a square key made of mild steel, the shear and crushing strength are related as
1205a) shear strength is equal to crushing strength
1206b) shear strength is greater than crushing strength
1207c) shear strength is less than crushing strength
1208d) none of the above
120951. In a bolt, the plane of shear should be across the threaded portion of the shank.
1210a) Correct
1211b) Incorrect
121252. A leaf spring in automobiles is used
1213a) to apply forces
121457
1215b) to measure forces
1216c) to absorb shocks
1217d) to store strain energy
121853. Two rigid plates are clamped by means of bolt and nut with an initial force F. After tightening, a separating force P (P < F) is applied to the lower plate, which in turn acts on the nut. The tension in the both after this is
1219a) F + P
1220b) F - P
1221c) P
1222d) F
122354. A shaft coupling should
1224a) be easy to connect or disconnect
1225b) transmit full power of the shaft
1226c) hold the shafts in perfect alignment
1227d) all of these
122855. The usual proportion for the width of key is (where d = Diameter of shaft or diameter of hole in the hub)
1229a) d/8
1230b) d/6
1231c) d/4
1232d) d/2
123356. The shear stress at a point in a shaft subjected to a torque is
1234a) directly proportional to the polar moment of inertia and to the distance of the point from the axis
123558
1236b) directly proportional to the applied torque and inversely proportional to the polar moment of inertia
1237c) directly proportional to the applied torque and the polar moment of inertia
1238d) inversely proportional to the applied torque and the polar moment of inertia
123957. Two concentric helical springs used to provide greater spring force are wound is opposite direction.
1240a) True
1241b) False
124258. In a transverse fillet welded joint, the size of weld is __________ the throat of weld.
1243a) 0.5 times
1244b) equal to
1245c) 2 times
1246d) double
124759. The function of the washer is to
1248a) Fill up the axial gap
1249b) provide bearing area
1250c) provide cushioning effect
1251d) absorb shocks and vibrations
125260. Which of the following coupling is used to connect two shafts which have both lateral and angular misalignment ?
1253a) Bushed pin type coupling
1254b) Universal coupling
1255c) Oldham coupling
1256d) all of these
125759
125861. The ends of the leaves of a semi-elliptical leaf spring are made triangular in order to
1259a) obtain variable moment of inertia (I) in each leaf
1260b) permit each leaf to act as a overhanging beam
1261c) have variable bending moment (M) in each leaf
1262d) make M/I constant throughout the length of the leaf
126362. An open coiled helical compression spring 'A' of mean diameter 50 mm is subjected to an axial load W. Another spring 'B' of mean diameter 25 mm is similar to spring 'A' in all respects. The deflection of spring 'B' will be __________ as compared to spring 'A'.
1264a) one-eighth
1265b) one-fourth
1266c) one-half
1267d) double
126863. When the bolt is very yielding as compared to the connected members, then the resultant load on the bolt will be equal to the
1269a) initial tension
1270b) external load applied
1271c) sum of the initial tension and external load applied
1272d) initial tension or external load, whichever is greater
127364. A rivet is specified by
1274a) shank diameter
1275b) length of rivet
1276c) type of head
1277d) length of tail
127860
127965. A saddle key __________ power through frictional resistance only.
1280a) transmits
1281b) does not transmit
128266. Which of the following statement is wrong ?
1283a) The solid length of a spring is the product of total number of coils and the diameter of the wire
1284b) The spring index is the ratio of mean diameter of the coil to the diameter of the wire
1285c) The spring stiffness is the load required per unit deflection of the spring
1286d) The pitch of the coil is the axial distance between adjacent coils in the compressed state
128767. A bolt is designed on the basis of __________ with a large factor of safety.
1288a) direct tensile stress
1289b) direct compressive stress
1290c) direct bending stress
1291d) direct shear stress
129268. A bolt of M 24 x 2 means that
1293a) the pitch of the thread is 24 mm and depth is 2 mm
1294b) cross-sectional area of the threads is 24 mm2
1295c) the nominal diameter of bolt is 24 mm and pitch is 2 mm
1296d) the effective diameter of bolt is 24 mm and there are 2 threads per cm
129769. In designing a sleeve coupling, outer diameter of the sleeve is taken as (where d = Diameter of the shaft)
1298a) d + 17 mm
1299b) 2 d + 13 mm
1300c) 2 d + 20 mm
130161
1302d) 3.5 d
130370. When a closely coiled helical spring is subjected to a couple about its axis, the stress induced in the wire material of the spring is
1304a) bending stress only
1305b) a combination of torsional shear stress and bending
1306c) direct shear stress only
1307d) a combination of bending stress and direct shear stress
130871. In a marine flange coupling, the pitch circle diameter of bolts is taken as
1309a) 1.2 d
1310b) 1.6 d
1311c) 2 d
1312d) 2.5 d
131372. In the calculation of induced shear stress in helical springs, the Wahl's stress factor is used to take care of
1314a) combined effect of transverse shear stress and bending stress in the wire
1315b) combined effect of bending stress and curvature of the wire
1316c) combined effect of transverse shear stress and curvature of wire
1317d) combined effect of torsional shear stress and transverse shear stress in the wire
131873. Which of the following key is preferred for the condition when a large amount of impact type torque is to be transmitted in both direction of rotation?
1319a) Woodruff key
1320b) Feather key
1321c) Gib-head key
1322d) Tangent key
132362
132474. Which of the following statement is wrong for a connecting rod ?
1325a) The connecting rod will be equally strong in buckling about X-axis and Y-axis, if Ixx= 4 Iyy
1326b) If Ixx > 4Iyy., the buckling will occur about Y-axis
1327c) If Ixx < 4Iyy., the buckling will occur about X-axis
1328d) The most suitable section for the connecting rod is T-section
132975. Factor of safety for fatigue loading is the ratio of
1330a) elastic limit to the working stress
1331b) elastic limit to the yield point
1332c) endurance limit to the working stress
1333d) Young's modulus to the ultimate tensile strength
133476. In a flange coupling, the keys are staggered at __________ along the circumference of the shafts in order to divide the weakening effect caused by key ways.
1335a) 90°
1336b) 135°
1337c) 160°
1338d) 180°
133977. Which one of the following loading is considered for the design of axles?
1340a) Bending moment only
1341b) Twisting moment only
1342c) Combined bending moment and twisting moments
1343d) Combined action of bending moment, twisting moment and axial thrust
134463
134578. When the connected members are very yielding (soft gasket) as compared to the bolt, then the resultant load on the bolt will be equal to the
1346a) initial tension
1347b) external load applied
1348c) sum of the initial tension and external load applied
1349d) initial tension or external load, whichever is greater
135079. A connecting rod should be
1351a) strong in buckling about X-axis
1352b) strong in buckling about Y-axis
1353c) equally strong in buckling about X-axis and Y-axis
1354d) any one of the above
135580. The diameter of the rivet hole is usually __________ the nominal diameter of the rivet.
1356a) equal to
1357b) less than
1358c) more than
135981. According to Indian standards, the diameter of rivet hole is made larger than the basic size of rivet by
1360a) 0.5 mm upto rivet diameter of 24 mm
1361b) 1 mm for rivet diameter from 27 mm to 36 mm
1362c) 2 mm for rivet diameter from 39 mm to 48 mm
1363d) all of the above
136482. Which of the following spring is used in mechanical wrist watch?
1365a) Helical compression spring
1366b) Spiral spring
136764
1368c) Torsion spring
1369d) Bellevile spring
137083. For a shaft diameter of 100 mm, the number of bolts in a flange coupling should be
1371a) 4
1372b) 6
1373c) 8
1374d) 10
137584. The design of pin of a rocker arm of an I.C. engine is based on
1376a) bearing failure
1377b) shearing failure
1378c) bending failure
1379d) all of these
138085. A double strap butt joint (with equal straps) is
1381a) always in single shear
1382b) always in double shear
1383c) either in single shear or double shear
1384d) any one of these
138586. The transverse fillet welded joints are designed for
1386a) tensile strength
1387b) compressive strength
1388c) bending strength
1389d) shear strength
139065
139187. When a helical compression spring is cut into halves, the stiffness of the resulting spring will be
1392a) same
1393b) double
1394c) one-half
1395d) one-fourth
139688. An universal coupling is a type of __________ coupling.
1397a) rigid
1398b) flexible
139989. A triple riveted butt joint with double straps of unequal width is to be designed for a boiler shell. The pitch of the rivets in the outer row is double the pitch in the inner row and zig-zag riveting is proposed. Which of the following statement is correct?
1400a) There are four rivets per pitch length, all in double shear
1401b) There are four rivets per pitch length, out of which two are in single shear and two are in double shear
1402c) There are five rivets per pitch length, all in double shear
1403d) There are five rivets per pitch length, out of which four are in double shear and one is in single shear
140490. The centre to centre distance between two consecutive rivets in a row, is called
1405a) margin
1406b) pitch
1407c) back pitch
1408d) diagonal pitch
140991. The tension on the slack side of the belt is __________ the tension on the tight side of the belt.
141066
1411a) equal to
1412b) less than
1413c) greater than
141492. The railway carriage couplings have
1415a) square threads
1416b) acme threads
1417c) knuckle threads
1418d) buttress threads
141993. The diameter of knuckle pin in a knuckle joint is usually taken as (where d = Diameter of the rod)
1420a) 0.5 d
1421b) 0.8 d
1422c) d
1423d) 1.2 d
142494. A spring of stiffness 1000 N/m is streteched initially by 100 mm from the undeformed position. The work required to stretch it by another 100 mm is
1425a) 5 N-m
1426b) 7 N-m
1427c) 10 N-m
1428d) 15 N-m
142995. A spring is used to
1430a) measure forces
1431b) apply forces
1432c) store energy
143367
1434d) all of these
143596. In order to have a connecting rod equally strong in buckling about X-axis and Y-axis, the moment of inertia about X-axis should be __________ the moment of inertia about Y-axis.
1436a) equal to
1437b) twice
1438c) three times
1439d) four times
144097. The acme threads are usually found on
1441a) spindles of bench vices
1442b) railway carriage couplings
1443c) feed mechanism of machine tools
1444d) screw cutting lathes
144598. The taper on cotter and slot is made on both the sides.
1446a) Agree
1447b) Disagree
144899. A cotter joint is used to connect two __________ rods.
1449a) co-axial
1450b) perpendicular
1451c) parallel
1452100. The permissible stress in the fillet weld is 100 N/mm2. The fillet weld has equal leg lengths of 15 mm each. The allowable shearing load on the weldment per cm length of the weld is
1453a) 7.5 kN
145468
1455b) 10.6 kN
1456c) 15 kN
1457d) 22.5 kN
1458Design of machine elements
14591. Hooks law holds good up to
1460a) Breaking point
1461b) Yield point
1462c) Elastic limit
1463d) Plastic limit
14642. A stud bolt is
1465a) Threaded on both ends
1466b) Threaded on one end only
1467c) Screawed into a tapped hole
1468d) None of the answers
14693. Which of the following key is under compression rather than in being shear when under load?
1470a) Saddle
1471b) Barth
1472c) Feather
1473d) Kennedy
147469
14754. Tangent key transmits force in
1476a) One direction only
1477b) Two directions
1478c) Both A and B
1479d) None of the answers
14805. The key will fail in which of the following maner?
1481a) Shearing
1482b) Crushing
1483c) Both Crushing and shearing
1484d) None of the answers
14856. Shaft is subjected to which of the following stresses?
1486a) Bending
1487b) Torsional
1488c) Both A and B
1489d) None of the answers
14907. In rail road car axles, which of the following bearing is used?
1491a) Partial
1492b) Fitted
1493c) Full
1494d) Linear
14958. Failure of material is called fatigue when it fails
1496a) At the elastic limit
1497b) Below the elasic limit
149870
1499c) At the yield point
1500d) Below the yield point
15019. The Resistance to fatigue of a material is measured by
1502a) Elastic limit
1503b) youngs modulus
1504c) Endurance limit
1505d) Ultimate tensile strength
150610. Factor of safety for fatigue loading is the ratio of
1507a) Elastic limit to the working stress
1508b) Endurance limit to the working stress
1509c) Youngs modulus to the Ultimate strength
1510d) Elastic limit to the yield point
151111. The ratio of shear stress to shear strain is called
1512a) Bulk modulus
1513b) Poisons ratio
1514c) Modulus of rigidity
1515d) Modulus of elasticity
151612. The modulus of elasticity of carbon steel is
1517a) 207000 N/mm 2
1518b) 100000 N/mm2
1519c) 50000 N/mm2
1520d) 80000 N/mm2
152171
152213. The modulus of elasticity of grey cast iron is
1523a) 207000 N/mm 2
1524b) 100000 N/mm2
1525c) 50000 N/mm2
1526d) 80000 N/mm2
152714. The modulus of rigidity of carbon steel is
1528a) 207000 N/mm 2
1529b) 100000 N/mm2
1530c) 50000 N/mm2
1531d) 80000 N/mm2
153215. The modulus of rigidity of carbon steel is
1533a) 207000 N/mm 2
1534b) 100000 N/mm2
1535c) 40000 N/mm2
1536d) 80000 N/mm2
153716. The poisons ration of carbon steel is
1538a) 0.4
1539b) 0.29
1540c) 0.21
1541d) 0.75
154217. When the diameter of shaft is doubled, its torque transmitting capacity will increased by
1543a) 8 times
1544b) 2 times
154572
1546c) 4 times
1547d) 16 times
154818. A component made of grey cast iron is designed on strength basis by
1549a) Ultimate tensile strength
1550b) Yield strength
1551c) Modulus of elasticity
1552d) Modulus of rigidity
155319. The thermal stresses are caused due to
1554a) Variation in teperature
1555b) High temperature
1556c) Specific heat
1557d) Latent heat
155820. The factor of safety for cast iron component, subjected to static force is usually
1559a) 1.2 to 4
1560b) 3 to 5
1561c) 1.5 to 2
1562d) 5 to 10
156321. The factor of safety for carbon steel component, subjected to static force is usually
1564a) 1.2 to 4
1565b) 3 to 5
1566c) 1.5 to 2
1567d) 5 to 10
156873
156922. A cotter joint is used to transmit
1570a) Axial tensile force only
1571b) Axial tensile and compressive forces
1572c) Axial compressive force only
1573d) Combined bending and twisting moment
157423. The tapper on cotter is usually
1575a) 1 in 24
1576b) 1 in 8
1577c) 1 in 100
1578d) 1 in 48
157924. A tapper is provided for cotter
1580a) Tightness in operation
1581b) wedge action
1582c) easy disassembly
1583d) All the answers
158425. The joint between the piston and cross head of steam engine is
1585a) knuckle joint
1586b) Universal joint
1587c) Cotter joint
1588d) Key loint
158926. The joint in Valve mechanism of reciprocating engine is
1590a) knuckle joint
1591b) Universal joint
159274
1593c) Cotter joint
1594d) Key loint
159527. The pin in knuckle joint is subjected to
1596a) Double shear stress
1597b) Torsional shear stress
1598c) Axial shear sress
1599d) Axial compressive stress
160028. The fulcrum pin of lever is designed on the basis of
1601a) Twisting moment
1602b) tensile force
1603c) Bending moment
1604d) Bearing pressure
160529. Rankines theory of failure is applicable to
1606a) Ductile materials
1607b) Brittle materials
1608c) elastic materials
1609d) plastic material
161030. Coulomb theory of failure applicable to
1611a) Ductile materials
1612b) Brittle materials
1613c) elastic materials
1614d) plastic material
161575
161631. Tresca theory of failure is applicable to
1617a) Brittle materials
1618b) Ductile materials
1619c) elastic materials
1620d) plastic material
162132. Guest theory of failure is applicable to
1622a) Brittle materials
1623b) plastic material
1624c) elastic materials
1625d) Ductile materials
162633. Distortion energy theory of failure is applicable to
1627a) Plain carbon steel
1628b) composites
1629c) cast iron
1630d) non - metals
163134. Stress concentration occurs dud to
1632a) Abrupt changes in Cross section
1633b) Discontinuity in material
1634c) Cracks and flaws
1635d) All the answers
163635. Stress concentration occurs at the contact between
1637a) Meshing teeth of driving and driven gears
1638b) cam and follower
163976
1640c) Balls and races
1641d) All the answers
164236. The maximum stress concentration factor for a rectangular plate with a transverse hole in tension or compression is
1643a) 2
1644b) 3
1645c) 2.5
1646d) 1
164737. In cyclic loading, the effect of stress concentration is more serious in case of
1648a) Brittle material
1649b) Ductile material
1650c) Both ductile and Brittle material
1651d) None of the answers
165238. A stress that varies sinusoidal manner with respect to time from zero to maximum valus and which hes same values for mean as well as amplitude is called
1653a) Reversed stress
1654b) Fluctuating stress
1655c) Repeated stress
1656d) Varrying stress
165739. A stress that varies sinusoidal manner with respect to time from minimum value to maximum value and which has same values for mean as well as amplitude is called
1658a) Reversed stress
1659b) Fluctuating stress
1660c) Repeated stress
166177
1662d) Varrying stress
166340. As the size of the componenet increases, the endurance limit of the component
1664a) Inceases
1665b) Decreases
1666c) Remains same
1667d) Increases up to 50 times
166878
1669DESIGN OF TRANSMISSION SYSTEMS
16701. Spherical roller bearings are normally used
1671a) For heavy radial loads
1672b) for heavy thrust loads
1673c) when there is less radial space
1674d) To compensate for angular misalignment
16752. The dynamic load capacity of a 6306 bearing is 22 kN. The maximum radial load it can sustain to operate at 600 rpm for 2000 hours is
1676a) 4.16 kN
1677b) 3.6 kN
1678c) 6.25 kN
1679d) 5.29 kN
16803. A band brake having band-width of 80 mm, drum diameter of 250 mm, coefficient of friction of 0.25 and angle of wrap of 270 degrees is required to exert a friction torque of 1000 Nm. The maximum tension (in kN) developed in the band
1681a) 1.88
1682b) 3.56
1683c) 6.12
1684d) 11.56
16854. Tooth interference in an external involute spur gear pair can be reduced by
168679
1687a) Decreasing center distance between gear pair
1688b) Decreasing module
1689c) Decreasing pressure angle
1690d) Increasing number of gear teeth
16915. A pair of spur gears with module 5 mm and a centre distance of 450 mm is used for a speed reduction of 5:1. The number of teeth on pinion is _____
1692a) 20
1693b) 25
1694c) 30
1695d) 40
16966. Which one of the following is used to convert a rotational motion into a translational motion?
1697a) Bevel gears
1698b) Double helical gears
1699c) Worm gears
1700d) Rack and pinion gears
17017. It is desired to avoid interference in a pair of spur gears having a 20 degree pressure angle. With increase in pinion to gear speed ratio, the minimum number of teeth on the pinion
1702a) Increases
1703b) decreases
1704c) first increases and then decreases
1705d) remains unchanged
170680
17078. Which of the bearings given below SHOULD NOT be subjected to a thrust load?
1708a) Deep groove ball bearing
1709b) Angular contact ball bearing
1710c) Cylindrical (straight) roller bearing
1711d) Single row tapered roller bearing
17129. A clutch has outer and inner diameters 100 mm and 40 mm respectively. Assuming a uniform pressure of 2 MPa and coefficient of friction of liner material is 0.4, the torque carrying capacity of the clutch is
1713a) 148 N-m
1714b) 196 N-m
1715c) 372 N-m
1716d) 490 N-m
171710. A spur gear has a module of 3 mm, number of teeth 16, a face width of 36 mm and a pressure angle of 20 degree. It is transmitting a power of 3 kW at 20 rev/sec. taking a velocity facor of 1.5, and a form factor of 0.3, the stress in the gear tooth is about
1718a) 32 MPa
1719b) 46 MPa
1720c) 58 MPa
1721d) 70 MPa
172211. Match the type of gears with their most appropriate description.
1723Type of gear Description
1724P. Helical gear 1. Axes non-parallel and non-intersecting
1725Q. Spiral Bevel 2. Axes parallel and teeth are inclined to the axis
1726R. Hypoid 3. Axes parallel and teeth are parallel to the axis
172781
1728S. Rack and pinion 4. Axes are perpendicular and intersecting, and teeth are
1729Inclined to the axis
17305. Axes are perpendicular and used for large speed reduction
17316. Axes parallel and one of the gears has infinite radius.
1732a) P-2, Q-4, R-1, S-6
1733b) P-1, Q-4, R-5, S-6
1734c) P-2, Q-6, R-4, S-2
1735d) P-6, Q-3, R-1, S-5
173612. A ball bearing operating at a load F has 8000 hours of life. The life of the bearing, in hours, when the load is doubled to 2F is
1737a) 8000
1738b) 6000
1739c) 4000
1740d) 1000
174113. A natural feed journal bearing of diameter 50 mm and length 50 mm operating at 20 revolution/second carries a load of 2 kN. The lubricant used has a viscosity of 20 mPa.s. The radial clearance is 50 μm. The Sommerfeld number for the bearing is
1742a) 0.062
1743b) 0.125
1744c) 0.250
1745d) 0.785
174614. A disc clutch is required to transmit 5 kW at 2000 rpm. The disc has a friction lining with coefficient of friction equal to 0.25. Bore radius of friction lining is equal to 25 mm. Assume uniform contact pressure of 1 MPa. The value of outside radius of the friction lining is
174782
1748a) 39.4 mm
1749b) 49.5 mm
1750c) 97.9 mm
1751d) 142.9 mm
175215. Twenty degree full depth involute profiled 19-tooth pinion and 37-tooth gear are in mesh. If the module is 5 mm, the center distance between the gear pair will be
1753a) 140 mm
1754b) 150 mm
1755c) 280 mm
1756d) 300 mm
175783
1758Design of Transmission Systems
17591. A sliding bearing which can support steady loads without any relative motion between the journal and the bearing is called
1760a) Zero film bearing
1761b) Boundary lubricated bearing
1762c) Hydrodynamic lubricated bearing
1763d) Hydrostatic lubricated bearing
17642. In a boundary lubricated bearing, there is a ................ of lubricant between the journal and the bearing.
1765a) Thick film
1766b) Thin film
1767c) Zero film
1768d) Solid film
17693. A bearing is designated by the number 405. It means that a bearing is of
1770a) Light series with bore of 25 mm
1771b) Medium series with bore of 25 mm
1772c) Heavy series with bore of 25 mm
1773d) Light series with width of 20 mm
17744. When the bearing is subjected to large fluctuations of load and heavy impacts, the bearing characteristic number should be ............... the bearing modulus.
1775a) 5 times
1776b) 10 times
1777c) 15 times
1778d) 20 times
177984
17805. When the length of the journal is equal to the diameter of the journal, then the bearing is said to be a
1781a) Short bearing
1782b) Long bearing
1783c) Medium bearing
1784d) Square bearing
17856. If Z = Absolute viscosity of the lubricant in kg/m-s, N = Speed of the journal in r.p.m., and p =Bearing pressure in N/mm2, then the bearing characteristic number is
1786a) Zp/n
1787b) Zn/p
1788c) Z/pn
1789d) pn/Z
17907. The ball bearings are usually made from
1791a) Low carbon steel
1792b) Medium carbon steel
1793c) High speed steel
1794d) Chrome nickel steel
17958. In radial bearings, the load acts
1796a) Along the axis of rotation
1797b) Perpendicular to the axis of rotation
1798c) parallel to the axis of rotation
1799d) in any direction
180085
18019. When the length of the journal is less than the diameter of the journal, then the bearing is said to be a
1802a) short bearing
1803b) long bearing
1804c) medium bearing
1805d) square bearing
180610. The angular contact ball bearing can be used for
1807a) Radial load only
1808b) axial load only
1809c) both radial and axial loads
1810d) to adjust for misalignments
181111. A bearing is designated by the number 305. It means that a bearing is of
1812a) Light series with bore of 25 mm
1813b) medium series with bore of 25 mm
1814c) Heavy series with bore of 25 mm
1815d) extra light series with width of 25 mm
181612. The spherical roller bearing can be used for
1817a) Radial load only
1818b) axial load only
1819c) both radial and axial loads
1820d) to adjust for misalignments
182186
182213. When the length of the journal is greater than the diameter of the journal, then the bearing is said to be a
1823a) short bearing
1824b) long bearing
1825c) medium bearing
1826d) square bearing
182714. A bearing is designated by the number 205. It means that a bearing is of
1828a) Light series with bore of 25 mm
1829b) medium series with bore of 25 mm
1830c) Heavy series with bore of 25 mm
1831d) extra light series with width of 25 mm
183215. If the centre distance of the mating gears having involute teeth is increased, then the pressure angle
1833a) increases
1834b) decreases
1835c) remains unchanged
1836d) none of these
183716. Lewis equation in spur gears is applied
1838a) only to the pinion
1839b) only to the gear
1840c) to stronger of the pinion or gear
184187
1842d) to weaker of the pinion or gear
184317. In helical gears, the distance between similar faces of adjacent teeth along a helix on the pitch cylinders normal to the teeth, is called
1844a) normal pitch
1845b) axial pitch
1846c) diametral pitch
1847d) module
184818. The root angle of a bevel gear is equal to
1849a) pitch angle – addendum angle
1850b) pitch angle + addendum angle
1851c) pitch angle – dedendum angle
1852d) pitch angle + dedendum angle
185319. The contact ratio for gears is
1854a) zero
1855b) less than one
1856c) greater than one
1857d) none of these
185820. The allowable static stress for steel gears is approximately __________of the ultimate tensile stress.
1859a) one-fourth
1860b) one-third
1861c) one-half
186288
1863d) double
186421. When bevel gears having equal teeth and equal pitch angles connect two shafts whose axes intersect at right angle, then they are known as
1865a) angular bevel gears
1866b) crown bevel gears
1867c) internal bevel gears
1868d) mitre gears
186922. When the spiral angle of a bevel gear is zero, it is called as_________
1870a) crown gear
1871b) zerol bevel gear
1872c) meter gear
1873d) spiral bevel gear
187423. The face angle of a bevel gear is equal to
1875a) pitch angle – addendum angle
1876b) pitch angle + addendum angle
1877c) pitch angle – dedendum angle
1878d) pitch angle + dedendum angle
187924. The property of a bearing material which has the ability to accommodate small particles of dust, grit etc., without scoring the material of the journal, is called
1880a) bondability
188189
1882b) embeddability
1883c) comformability
1884d) fatigue strength
188525. The material used for lining of friction surfaces of a clutch should have ............ coefficient of friction.
1886a) low
1887b) high
1888c) medium
1889d) zero
189026. In case of a multiple disc clutch, if n1 are the number of discs on the driving shaft and n2 are the number of the discs on the driven shaft, then the number of pairs of contact surfaces will be
1891a) n1 + n2
1892b) n1 + n2 – 1
1893c) n1 + n2 + 1
1894d) none of these
189527. A jaw clutch is essentially a
1896a) Positive action clutch
1897b) cone clutch
1898c) friction clutch
1899d) disc clutch
190090
190128. The cone clutches have become obsolete because of
1902a) small cone angles
1903b) exposure to dirt and dust
1904c) difficulty in disengaging
1905d) all of these
190629. To restore stable operating condition in a hydrodynamic journal bearing, when it encounters higher magnitude of loads,
1907a) oil viscosity is to be decreased
1908b) oil viscosity is to be increased
1909c) oil viscosity index is to be increased
1910d) oil viscosity index is to be decreased
191130. Total slip will occur in a belt drive when
1912a) angle of rest is zero
1913b) angle of creep is greater than angle of rest
1914c) angle of rest is greater than angle of creep
1915d) angle of creep is zero
191631. To make a worm drive reversible, it is necessary to increase
1917a) centre distance
1918b) worm diameter factor
1919c) number of starts
1920d) reduction ratio
192132. the basic load rating of a ball bearing is
192291
1923a) the maximum static radial load that can be applied without causing any plastic deformation of bearing components.
1924b) the radial load at which 90% of the group of apparently identical bearings run for one million revolutions before the first evidence of failure.
1925c) the maximum radial load that can be applied during operation without any plastic deformation of bearing components.
1926d) a combination of radial and axial loads that can be applied without any plastic deformation
192733. The difference between tensions on the tight and slack sides of a belt drive is 3000 N. if the belt speed is 15 m/s, the transmitted power in kW is
1928a) 45
1929b) 22.5
1930c) 90
1931d) 100
193234. With regard to belt drives with given pulley diameters, centre distance and coefficient of friction between the pulley and the belt materials, which of the statement below are FALSE?
1933a) a crossed flat belt configuration can transmit more power than an open flat belt configuration
1934b) a V-belt has greater power transmission capacity than an open flat belt
1935c) power transmission is greater when belt tension is higher due to centrifugal effects than the same belt drive when centrifugal affects are absent.
1936d) power transmission is the greatest just before the point of slipping is reached.
193735. the ratio of tension on the tight side to that on the slack side in a flat belt drive is
1938a) proportional to the product of coefficient of friction and lap angle
1939b) an exponential function of the product of coefficient of friction and lap angle
1940c) proportional to the lap angle
194192
1942d) proportional to the coefficient of friction
194336. A 1.5 kW motor is running at 1440 rev/min, it is to be connected to a stirrer running at 36 rev/min. The gearing arrangement suitable for this application is
1944a) Differential gear
1945b) helical gear
1946c) bevel gear
1947d) worm gear
194837. For transmission of the power between the shafts which are parallel to each other. The gearing arrangement suitable for this application is
1949a) Differential gear
1950b) helical gear
1951c) bevel gear
1952d) worm gear
195338. For transmission of the power between the shafts which are intersecting each other. The gearing arrangement suitable for this application is
1954a) spur gear
1955b) helical gear
1956c) bevel gear
1957d) worm gear
195839. For transmission of the power between the shafts which are nonintersecting and nonparallel to each other. The gearing arrangement suitable for this application is
1959a) Differential gear
1960b) helical gear
1961c) bevel gear
196293
1963d) worm gear
196440. The life of a ball bearing at a load of 10 kN is 8000 hours. It’s life in hours, if the load is increased to 20 kN, keeping all other conditions the same, is
1965a) 4000
1966b) 2000
1967c) 1000
1968d) 500
196941. The minimum number of teeth on the pinion to operate without interference in standard full height involute teeth gear mechanism with 20 degree pressure angle is
1970a) 14
1971b) 12
1972c) 18
1973d) 32
197442. The minimum number of teeth on the pinion to operate without interference in standard stub involute teeth gear mechanism with 20 degree pressure angle is
1975a) 14
1976b) 12
1977c) 18
1978d) 32
197943. The minimum number of teeth on the pinion to operate without interference in standard full height involute teeth gear mechanism with 14.5 degree pressure angle is
1980a) 14
1981b) 12
1982c) 18
198394
1984d) 32
198544. The minimum number of teeth on the pinion to operate without interference in standard composite teeth gear mechanism with 14.5 degree pressure angle is
1986a) 14
1987b) 12
1988c) 18
1989d) 32
199045. Large speed reductions (greater than 20) in one stage of a gear train are possible through
1991a) spur gearing
1992b) worm gearing
1993c) bevel gearing
1994d) helical gearing
199546. A wire rope is designated as 6 x 19 standard hoisting. The numbers 6 x 19 represent
1996a) diameter in millimeter x length in meter
1997b) diameter in centimeter x length in meter
1998c) number of strands x number of wires in each strand
1999d) number of wires in each strand x number of strands
200047. In a band brake the ratio of tight side band tension to the tension on slack side is 3. If the angle of overlap of band on the drum is 1800 the coefficient of friction required between drum and the band is
2001a) 0.20
2002b) 0.25
2003c) 0.30
2004d) 0.35
200595
200648. Two mating spur gears have 40 and 120 teeth respectively. The pinion rotates at 1200 rpm and transmits a torque of 20 N-m. The torque transmitted by the gear is
2007a) 6.6 N-m
2008b) 20 N-m
2009c) 40 N-m
2010d) 60 N-m
201149. Match the following
2012Type of gears Arrangement of shafts
2013P. Bevel gears 1. Non-parallel off-set shafts
2014Q. Worm gears 2. Non-parallel intersecting shafts
2015R. Herringbone gears 3. Non-parallel, non-intersecting shafts
2016S. Hypoid gears 4. Parallel shafts
2017a) P-4 Q-2 R-1 S-3
2018b) P-2 Q-3 R-4 S-1
2019c) P-3 Q-2 R-1 S-4
2020d) P-1 Q-3 R-4 S-2
202150. Which of the following is a criterion in the design of hydrodynamic journal bearings?
2022a) Rotation factor
2023b) rating life
2024c) Specific dynamic capacity
2025d) Sommerfeld number
202696
202751. A disc clutch is required to transmit 5 kW at 2000 rpm. The disc has a friction lining with coefficient of friction equal to 0.25. Bore radius of friction lining is equal to 25 mm. Assume uniform contact pressure of 1 MPa. The value of outside radius of the friction lining is
2028a) 39.4 mm
2029b) 49.5 mm
2030c) 97.9 mm
2031d) 142.9 mm
203252. Twenty degree full depth involute profiled 19-tooth pinion and 37-tooth gear are in mesh. If the module is 5 mm, the center distance between the gear pair will be
2033a) 140 mm
2034b) 150 mm
2035c) 280 mm
2036d) 300 mm
203753. A ball bearing operating at a load F has 8000 hours of life. The life of the bearing, in hours, when the load is doubled to 2F is
2038a) 8000
2039b) 6000
2040c) 4000
2041d) 1000
204254. A natural feed journal bearing of diameter 50 mm and length 50 mm operating at 20 revolution/second carries a load of 2 kN. The lubricant used has a viscosity of 20 mPa.s. The radial clearance is 50 μm. The Sommerfeld number for the bearing is
2043a) 0.062
2044b) 0.125
2045c) 0.250
2046d) 0.785
204797
204855. A clutch has outer and inner diameters 100 mm and 40 mm respectively. Assuming a uniform pressure of 2 MPa and coefficient of friction of liner material is 0.4, the torque carrying capacity of the clutch is
2049a) 148 N-m
2050b) 196 N-m
2051c) 372 N-m
2052d) 490 N-m
205356. A spur gear has a module of 3 mm, number of teeth 16, a face width of 36 mm and a pressure angle of 20 degree. It is transmitting a power of 3 kW at 20 rev/sec. taking a velocity facor of 1.5, and a form factor of 0.3, the stress in the gear tooth is about
2054a) 32 MPa
2055b) 46 MPa
2056c) 58 MPa
2057d) 70 MPa
205857. Match the type of gears with their most appropriate description.
2059Type of gear Description
2060P. Helical gear 1. Axes non-parallel and non-intersecting
2061Q. Spiral Bevel 2. Axes parallel and teeth are inclined to the axis
2062R. Hypoid 3. Axes parallel and teeth are parallel to the axis
2063S. Rack and pinion 4. Axes are perpendicular and intersecting, and teeth are
2064Inclined to the axis
20655. Axes are perpendicular and used for large speed reduction
20666. Axes parallel and one of the gears has infinite radius.
206798
2068a) P-2, Q-4, R-1, S-6
2069b) P-1, Q-4, R-5, S-6
2070c) P-2, Q-6, R-4, S-2
2071d) P-6, Q-3 , R-1, S-5
207258. A band brake having band-width of 80 mm, drum diameter of 250 mm, coefficient of friction of 0.25 and angle of wrap of 270 degrees is required to exert a friction torque of 1000 N-m. the maximum tension (in kN) developed in the band is
2073a) 1.88
2074b) 3.56
2075c) 6.12
2076d) 11.56
207759. A lightly loaded full journal bearing has journal diameter of 50 mm, bush bore of 50.05 mm and bush length of 20 mm. If rotational speed of journal is 1200 rpm and average viscosity of liquid lubricant is 0.03 Pa-sec, the power loss(in W) will be
2078a) 37
2079b) 74
2080c) 118
2081d) 237
208260. In involute gears, the pressure angle is
2083a) dependent on the size of teeth
2084b) dependent on the size of gears
2085c) always constant
2086d) always variable
208799
2088100
2089DESIGN OF TRANSMISSION SYSTEMS
20901. Starting friction is low in
2091a) Hydrostatic lubrication
2092b) Hydrodynamic lubrication
2093c) Semi-fluid lubrication
2094d) Boundary lubrication
20952. The most suitable bearing for resisting heavy loads under slow speed is
2096a) Hydrodynamic bearing
2097b) ball bearing
2098c) Roller bearing
2099d) Hydrostatic bearing
21003. Pivoted segment thrust bearing is used to provide
2101a) Uniform distribution of load
2102b) uniform wear
2103c) Converging film of oil
2104d) easy flow of oil
21054. In the design of connecting rod small end bearing, the value of permissible bearing pressure to be used is
2106a) Less than that used for big end bearing
2107b) more than that used for big end bearing
2108c) Equal to that used for big end bearing
2109101
2110d) none of the above
21115. Removal of metal particles from the race-way of a rolling contact bearing is a king of failure of bearing, known as
2112a) Pitting
2113b) wearing
2114c) spalling
2115d) scuffing
21166. Which of the following is an anti-friction bearing
2117a) Pedestal bearing
2118b) Collar bearing
2119c) Hydrostatic bearing
2120d) Needle bearing
21217. Basic dynamic load of a ball or roller bearing, determine its
2122a) Life expectancy
2123b) axial thrust
2124c) stress
2125d) size
21268. Creep in belt drive is due to
2127a) Material of the belt
2128b) material of the pulley
2129102
2130c) Uneven extensions and contractions due to varying tension
2131d) expansion of belt
21329. In a horizontal flat belt drive, it is customary to use
2133a) Bottom side of belt as slack side
2134b) top side of the belt as slack side
2135c) crossed belting
2136d) idler in-between
213710. In a belt drive, the coefficient of friction at the smaller pulley
2138a) Must be same as that at bigger pulley
2139b) must be less than that at bigger pulley
2140c) Must be more than that at bigger pulley
2141d) Can be same or different from that at bigger pulley
214211. The length of V-belt is designated by
2143a) Inside length
2144b) outside length
2145c) length at the centre of belt
2146d) none of the above
214712. In a multiple V-belt drive; when a single belt is damaged, it is preferable to change the complete set, to
2148103
2149a) Reduce vibration
2150b) reduce slip
2151c) ensure uniform loading
2152d) ensure proper alignement
215313. In the design of cast pulleys; curved arms, joining rim to the hub are used, in order to
2154a) Reduce distortion or tearing
2155b) improve strength
2156c) improve aesthetics
2157d) aid in balancing the pulley
215814. Wire ropes are used for applications, experiencing
2159a) Low speeds and low tension
2160b) low speeds and high tension
2161c) High speeds and low tension
2162d) high speeds and high tension
216315. In the designation 6 x 19 for the wire rope; 6 and 19 stand for
2164a) Diameter of wire rope and number of strands
2165b) Diameter of wire rope and number of wires
2166c) Number of wires and number of strands
2167d) Number of strands and number of wires
2168104
216916. In order to have smooth operation, the minimum number of teeth on the smaller sprocket should be
2170a) 15
2171b) 17
2172c) 21
2173d) 25
217417. The size of a gear is specified by
2175a) Addendum circle diameter
2176b) pitch circle diameter
2177c) dedundum circle diameter
2178d) base circle diameter
217918. In involute gears, the pressure angle is
2180a) Dependent on the size of the teeth
2181b) dependent on the size of the gear
2182c) always constant
2183d) always variable
218419. In which type of teeth, variation in centre distance, within certain limits, does not affect the velocity ratio of the mating gears
2185a) Cycloidal
2186b) involute
2187c) hypoid
2188105
2189d) epicycloid
219020. Interference is inherently absent in the following types of gears:
2191a) Involute
2192b) Stub
2193c) cycloidal
2194d) Epi-cycloid
219521. If both the pinion and gear are made of the same material, then the power transmitting capacity is decided by
2196a) Gear
2197b) Pinion
2198c) pinion or gear
2199d) both pinion and gear
220022. For the possible wear to be permitted in a gear drive,
2201a) Wear load should be greater than the dynamic load
2202b) Wear load should be less than the dynamic load
2203c) Wear load should be greater than the beam strength
2204d) Wear load should be greater than the tangential tooth load
220523. The role of hunting tooth in a gear drive is that it
2206106
2207a) Increases efficiency of transmission
2208b) distributes wear uniformly
2209c) reduces vibration
2210d) permits stable operation
221124. The transverse section of a helical gear is identical to
2212a) Bevel gear
2213b) spur gear
2214c) worm gear
2215d) none of the above
221625. In helical gears, the right hand helix will mesh with
2217a) Right hand helix
2218b) left hand helix
2219c) both of the above
2220d) none of the above
222126. Zero axial thrust is experienced in
2222a) Helical gears
2223b) bevel gears
2224c) spiral gears
2225d) herringbone gears
2226107
222727. Helical gears are used for
2228a) External meshing only
2229b) either external or internal meshing
2230c) internal meshing only
2231d) none of the above
223228. Angular bevel gears are the gears mounted on intersecting shafts which make an angle ______ degree
2233a) 90
2234b) less than 90
2235c) more than 90
2236d) other than 90
223729. For a crown (bevel ) gear, shaft angle is ____ degree
2238a) 90
2239b) 45
2240c) 180
2241d) 0
224230. Mitre gears are
2243a) Right angled bevel gears, having the same number of teeth
2244b) Spur gears of equal diameter and pitch
2245c) Helical gears of same module
2246108
2247d) A kind of worm and worm gear
224831. In a worm drive, the axial pitch of the worm is
2249a) Equal to circular pitch of the gear
2250b) Equal to half the circular pitch of the gear
2251c) Equal to twice the circular pitch of the gear
2252d) None of the above
225332. The gear reduction of a worm gear set, with worm gear of 50 teeth and worm of double start threads, would be
2254a) 50:1
2255b) 100:1
2256c) 25:1
2257d) none of the above
225833. If the lead angle of a worm is 20 degree, then the helix angle will be_____ degree.
2259a) 20
2260b) 70
2261c) 80
2262d) none of the above
226334. In a worm drive, with self-locking feature,
2264109
2265a) Worm only can act as a driver
2266b) Worm wheel only can act as a driver
2267c) Either worm or worm wheel can act as a driver
2268d) None of the above
226935. A jaw clutch is a
2270a) Positive clutch
2271b) friction clutch
2272c) centrifugal clutch
2273d) cone clutch
227436. The friction torque, with the assumption of uniform pressure, compared to uniform wear is
2275a) Same
2276b) greater
2277c) lower
2278d) could be anything
227937. A multi-disc clutch has three discs on the driving shaft and two discs on the driven shaft. Number of pairs of contact surfaces is
2280a) 2
2281b) 3
2282c) 4
2283d) 5
228438. Brakes convert
2285110
2286a) Heat energy to kinetic energy
2287b) Kinetic energy or potential energy into heat energy
2288c) Heat energy into potential energy
2289d) Kinetic energy into potential energy
229039. The brake commonly used on locomotive bogies is
2291a) Internal expanding brake
2292b) band and block brake
2293c) shoe brake
2294d) band brake
229540. The type of brake used in motor cars is
2296a) Block or shoe brake
2297b) band brake
2298c) band and block brake
2299d) internal expanding shoe brake
2300111
23011. Critical damping is afunction of
2302a) mass and stiffness
2303b) mass and damping co-efficient
2304c) stiffness and natural frequency
2305d) natural frequency and damping co-efficient
23062. The amplitude of underdamping a small damping varies with time as
2307a) linearly
2308b) arithmetically
2309c) geometrically
2310d) exponenially
23113. Ratio of two successive oscillations in an underdamped system is
2312a) constant
2313b) linear
2314c) logarithmic
2315d) exponential
23164. Critical or whirling speed is the speed at which the shaft tends to vibrate violently in
2317a) transverse direction
2318b) longitudinal direction
2319c) linear direction
2320d) none of the above
23215. Rotating shafts tend to of vibrate violently at whirling speeds because
2322112
2323a) the shafts are rotating at vary speeds
2324b) bearing centre line coincide with the shaft axis
2325c) the system is unbalanced
2326d) resonance is caused due to the heavy weight of the rotor
23276. The natural frequency of an undamped vibrating system is 100 rad/s. A damper with a damping factor of 0.8 is introduced into the system. The frequency of vibration of the damped system, in rad/s is
2328a) 60
2329b) 75
2330c) 80
2331d) 100
23327. The un-damped natural frequency oscillations of the bar about the hinge point is
2333a) 42.43 rad/s
2334b) 30 rad/s
2335c) 17.32 rad/s
2336d) 14.14 rad/s
23378. The earth can be assumed as a uniform sphere. Suppose the earth shrinks by 1% in diameter, then new day period
2338a) not change from 24 hrs.
2339b) reduce by about 2%
2340c) reduce by about 1%
2341d) increase by about 1%
23429. Whirling speed of a shaft coincide with the natural frequency of the
2343a) longitudinal vibration
2344113
2345b) transverse vibration
2346c) torsional vibration
2347d) coupled between torsional vibration
234810. The damping coefficient in the vibration equation is given by
2349a) 500 Nms/rad
2350b) 500 N/(m/s)
2351c) 80 Nms/rad
2352d) 80 N/(m/s)
2353Dynamics of Machinery
23541. When the ratio of excitation freuency to natural frequency is 1.414 ,then transmissibility ratio will be
2355a) infinite
2356b) 1
2357c) <1
2358d) >1
23592. Critical speed of a shaft with a disc supported in between is equal to the natural frequency of the system in
2360a) Torsional vibrations
2361b) Longitudinal vibrations
2362c) Transverse vibration
2363d) Longitudinal vibration provided the shaft is vertical
2364114
23653. If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the later at the same speed will be
2366a) Four times the first one
2367b) Same as the first one
2368c) One fourth of the first one
2369d) One and half times the first one
23704. The deflection of a spring with 20 active turns under a load of 1000N is 10 mm.The springs is made into two pieces each of 10 active coils and places in parallel under the same load. The deflection of this system is
2371a) 10 mm
2372b) 20 mm
2373c) 10 mm
2374d) 2.5 mm
23755. In a four cylinder 4 stroke inline IC engine, the angle between two successive crank should be 180 degree.But this rule is violated for cranks 2 and 3 (i.e. inner cranks) and the angle is made 0 degree.This is done to achieve primary force
2376a) and secondary force balancing
2377b) and secondary couple balancing
2378c) primary and secondary couple balancing
2379d) secondary force and primary couple balancing
23806. If the speed of the engine varies between 390 and 410 rpm in a cycle of operation, the coefficient of fluctuation of speed will be
2381a) 0.01
2382b) 0.02
2383c) 0.05
2384d) 0.07
2385115
23867. In a flywheel, the safe stress is 25.2 MN/m2 and the density is 7 g/cm3.Then what is the maximum peripheral velocity (in m/s)?
2387a) 30
2388b) 60
2389c) 45
2390d) 120
23918. A reciprocating engine, running at 80rad/s, is supported on springs. The static deflection of the spring is 1mm.Take g=10m/s2.when the engine runs what will be the frequency of vibration of the system?
2392a) 100 rad/s
2393b) 120 rad/s
2394c) 80 rad/s
2395d) 90 rad/s
23969. The static deflection of a shaft under a flywheel is 4 mm. Take g=10m/s2.What is the critical speed in rad/s?
2397a) 20
2398b) 50
2399c) 40
2400d) 2.5
240110. Hammer blow
2402a) is the maximum horizontal unbalanced force caused by the mass provided to balance the reciprocating masses.
2403b) is the maximum vertical unbalanced force caused by the mass added to balance the reciprocating masses
2404c) varies as the square root of the speed
2405116
2406d) varies inversely with the square of the speed
240711. The balancing weights are introduced in planes parallel to the plane of rotation of the disturbing mass. To obtain complete dynamic balance, the minimum number of balancing weights to be introduced in different planes is
2408a) 1
2409b) 2
2410c) 3
2411d) 4
241212. Critical damping is a function of
2413a) Mass and damping coefficient
2414b) Mass and stiffness
2415c) Stiffness and natural frequency
2416d) Natural frequency and damping coefficient
241713. Whirling speed of the shaft is the speed at which
2418a) Shaft tends to vibrate in longitudinal direction
2419b) torsional vibrations occur
2420c) shaft tends to vibrate vigorously in transverse direction
2421d) combination of transverse and longitudinal vibration occurs
242214. In a system subjected to damped forced vibrations, the ratio of maximum displacement to the static deflection is known as
2423a) Critical damping ratio
2424b) Damping factor
2425c) Logarithmic decrement
2426d) Magnification factor
2427117
242815. For steady state forced vibrations, the phase lag at resonance is
2429a) 0°
2430b) 45°
2431c) 90°
2432d) 180°
243316. In reciprocating engines primary forces
2434a) are completely balanced
2435b) are partially balanced
2436c) are balanced by secondary forces
2437d) cannot be balanced
243817. A governor is said to be isochronous when the equilibrium speed for all radii of rotation of the balls within the working range
2439a) is not constant
2440b) is constant
2441c) varies uniformly
2442d) has uniform acceleration
244318. When the sleeve of a Porter governor moves upwards, the governor speed
2444a) increases
2445b) first increases and then decreases
2446c) decreases
2447d) remains unaffected
2448118
244919. When the speed of the engine fluctuates continuously above and below the mean speed, the governor is said to be
2450a) hunt
2451b) unstable
2452c) isochronous
2453d) stable
245420. In a four stroke I.C. engine, the turning moment during the compression stroke is
2455a) negative during major portion of the stroke
2456b) negative throughout
2457c) positive throughout
2458d) positive during major portion of the stroke
245921. when a ship travels in a sea, which of the effect is more dangerous
2460a) steering
2461b) pitching
2462c) rolling
2463d) steering and rolling
246422. The engine of an aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane
2465takes a turn to the left. The effect of the gyroscopic couple on the aeroplane will be
2466119
2467a) to raise the nose and dip the tail
2468b) to dip the nose and raise the tail
2469c) to raise the nose and tail
2470d) to dip the nose and tail
247123. The air screw of an aeroplane is rotating clockwise when looking from the front. If it makes a left turn,
2472the gyroscopic effect will
2473a) tend to depress the nose and raise the tail
2474b) tend to raise the nose and depress the tail
2475c) tilt the aeroplane
2476d) roll the aeroplane
247724. In an automobile, if the vehicle makes a left turn, the gyroscopic torque
2478a) increases the forces on the outer wheels
2479b) decreases the forces on the outer wheels
2480c) does not affect the forces on the outer wheels
2481d) increases the forces on the inner wheels
248225. A motor car moving at a certain speed takes a left turn in a curved path. If the engine rotates in the
2483same direction as that of wheels, then due to the centrifugal forces
2484a) the reaction on the inner wheels increases and on the outer wheels decreases
2485b) the reaction on the outer wheels increases and on the inner wheels decreases
2486c) the reaction on the front wheels increases and on the rear wheels decreases
2487120
2488d) the reaction on the rear wheels increases and on the front wheels decreases
248926. A rigid body, under the action of external forces, can be replaced by two masses placed at a fixed
2490distance apart. The two masses form an equivalent dynamical system, if
2491a) the sum of two masses is equal to the total mass of the body
2492b) the centre of gravity of the two masses coincides with that of the body
2493c) the sum of mass moment of inertia of the masses about their centre of gravity is equal to the mass
2494moment of inertia of the body
2495d) all of these
249627. In an engine, the work done by inertia forces in a cycle is
2497a) positive
2498b) zero
2499c) negative
2500d) infinite
250128. The maximum fluctuation of energy is the
2502a) sum of maximum and minimum energies
2503b) difference between the maximum and minimum energies
2504c) ratio of the maximum energy and minimum energy
2505d) ratio of the mean resisting torque to the work done per cycle
2506121
250729. In a turning moment diagram, the variations of energy above and below the mean resisting torque line
2508is called
2509a) fluctuation of energy
2510b) maximum fluctuation of energy
2511c) coefficient of fluctuation of energy
2512d) minimum fluctuation of energy
251330. The equation of motion for a viscous damped vibration is 3 d2x/dt2 + 9dx/dt + 27x = 0. The damping factor will be
2514a) 0.25
2515b) 0.5
2516c) 0.75
2517d) 1
251831. The ratio of the maximum fluctuation of speed to the mean speed is called
2519a) fluctuation of speed
2520b) maximum fluctuation of speed
2521c) coefficient of fluctuation of speed
2522d) minimum fluctuation of speed
252332. The primary unbalanced force is maximum when the angle of inclination of the crank with the line
2524of stroke is
2525a) 0°
2526122
2527b) 90°
2528c) 180°
2529d) 360°
253033. The partial balancing means
2531a) balancing partially the revolving masses
2532b) balancing partially the reciprocating masses
2533c) best balancing of engines
2534d) complete balancing
253534. A flywheel of moment of inertia 9.8 kgm2 fluctuates by 30 rpm for a fluctuation in energy of 1936 Joules. The mean speed of the flywheel is (in rpm)
2536a) 600
2537b) 900
2538c) 968
2539d) 2940
254035. In order to facilitate the starting of locomotive in any position, the cranks of a locomotive, with two
2541cylinders, are placed at . . . . . . to each other.
2542a) 45°
2543b) 90°
2544c) 120°
2545d) 180°
2546123
254736. In a locomotive, the ratio of the connecting rod length to the crank radius is kept very large in order to
2548a) minimise the effect of primary forces
2549b) minimise the effect of secondary forces
2550c) have perfect balancing
2551d) start the locomotive quickly
255237. The swaying couple is maximum or minimum when the angle of inclina
2553of stroke ( θ ) is equal to
2554a) 45° and 135°
2555b) 90° and 135°
2556c) 135° and 225°
2557d) 45° and 225°
255838. The tractive force is maximum or minimum when the angle of inclination of the crank to the line of
2559stroke ( θ ) is equal to
2560a) 90° and 225°
2561b) 135° and 180°
2562c) 180° and 225°
2563d) 135° and 315°
256439. The swaying couple is due to the
2565a) primary unbalanced force
2566124
2567b) secondary unbalanced force
2568c) two cylinders of locomotive
2569d) partial balancing
257040. In a locomotive, the maximum magnitude of the unbalanced force along the perpendicular to the
2571line of stroke, is known as
2572a) tractive force
2573b) swaying couple
2574c) hammer blow
2575d) pullout
257641. Secondary forces in reciprocating mass on engine frame are
2577a) of same frequency as of primary forces
2578b) twice the frequency as of primary forces
2579c) four times the frequency as of primary forces
2580d) half times the frequency as of primary forces
258142. Which of the following statement is correct?
2582a) In any engine, 100% of the reciprocating masses can be balanced dynamically
2583b) In the case of balancing of multicylinder engine, the value of secondary force is higher than
2584the value of the primary force
2585c) In the case of balancing of multimass rotating systems, dynamic balancing can be directly
2586started without static balancing done to the system
2587125
2588d) In the case of balancing of multicylinder engine, the value of secondary force is lower than
2589the value of the primary force
259043. For static balancing of a shaft,
2591a) the net dynamic force acting on the shaft is equal to zero
2592b) the net couple due to the dynamic forces acting on the shaft is equal to zero
2593c) the net dynamic force acting on the shaft is equal to infinite
2594d) the net couple due to the dynamic forces acting on the shaft is equal to infinite
259544. For dynamic balancing of a shaft,
2596a) the net dynamic force acting on the shaft is equal to zero
2597b) the net couple due to dynamic forces acting on the shaft is equal to zero
2598c) the net dynamic force acting on the shaft is equal to infinite
2599d) the net couple due to the dynamic forces acting on the shaft is equal to infinite
260045. In order to have a complete balance of the several revolving masses in different planes
2601a) the resultant force must be zero
2602b) the resultant couple must be zero
2603c) both the resultant force and couple must be zero
2604d) the resultant couple must be infinite
260546. The Bifilar suspension method is used to determine
2606a) Mass moment of inertia
2607b) position of balancing weights
2608126
2609c) centripetal acceleration
2610d) angular accelaration of the body
261147.
2612In a vibrating system, if the actual damping coefficient is 40 N/m/s and critical damping coefficient is 420 N/m/s, then logarithmic decrement is equal to
2613a) 0.2
2614b) position of balancing weights
2615c) centripetal acceleration
2616d) angular accelaration of the body
261748. When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
2618a) 1
2619b) position of balancing weights
2620c) centripetal acceleration
2621d) angular accelaration of the body
262249. The factor which affects the critical speed of a shaft is
2623a) diameter of disc
2624b) span of shaft
2625c) eccentricity
2626d) diameter of disc,span of shaft and eccentricity
262750.
2628127
2629If the ratio of frequency of excitation to the natural frequency of vibrations is 1.414, then the transmissibility of vibration will the
2630a) 1
2631b) 2
2632c) 0.5
2633d) 0
263451. In under damped vibrating system, the amplitude of vibration
2635a) decreases linearly with time
2636b) increases linearly with time
2637c) decreases exponentially with time
2638d) increases exponentially with time
263952. The steering of a ship means
2640a) movement of a complete ship up and down in vertical plane about transverse axis
2641b) turning of a complete ship in a curve towards right or left, while it moves forward
2642c) rolling of a complete ship side-ways
2643d) tilting of a complete ship
264453. A Hartnell governor is a
2645a) dead weight governor
2646b) pendulum type governor
2647c) spring loaded governor
2648d) inertia governor
2649128
265054. A shaft carrying three rotors will have
2651a) no node
2652b) one node
2653c) two nodes
2654d) three nodes
265555. When a rigid body is suspended vertically and it oscillates with a small amplitude under the action of the force of gravity, the body is known as
2656a) torsional pendulum
2657b) simple pendulum
2658c) second's pendulum
2659d) compound pendulum
266056. The secondary unbalanced force is maximum __________ in one revolution of the crank.
2661a) four times
2662b) two times
2663c) eight times
2664d) sixteen times
266557. For two governors A and B, the lift of sleeve of governor A is more than that of governor B, for a given fractional change in speed. It indicates that
2666a) governor A is more sensitive than governor B
2667b) both governors A and B are equally sensitive
2668c) governor B is more sensitive than governor A
2669d) both governors A and B are isochronous
2670129
267158. In order to double the period of a simple pendulum, the length of the string should be
2672a) halved
2673b) both governors A and B are equally sensitive
2674c) governor B is more sensitive than governor A
2675d) both governors A and B are isochronous
267659. Which of the following is used to control the speed variations of the engine caused by the fluctuations of the engine turning moment?
2677a) Governor
2678b) flywheel
2679c) connecting rod
2680d) piston
268160. A system in dynamic balance implies that
2682a) there will absolutely no wear of bearings
2683b) there is no critical speed in the system
2684c) the system is critically damped
2685d) the system is also statically balanced
268661. The coriolis component of acceleration leads the sliding velocity by
2687a) 45°
2688b) 135°
2689130
2690c) 90°
2691d) 180°
269262. In a spring mass vibrating system, the natural frequency of vibration is reduced to half the value when a second spring is added to the first spring in series. Determine the stiffness of the second in terms of that of the first spring.
2693a) 1/3 of first spring
2694b) 3 times of first spring
2695c) 2 times of first spring
2696d) as the same of first spring
269763. What is the minimum damping ratio for an underdamped system such that its overshoot is limited
2698to 10 percent.
2699a) 0.59
2700b) 0.69
2701c) 1
2702d) 1.59
270364. Which of the following statement is correct ?
2704a) The acceleration of the particle moving with simple harmonic motion is maximum at the mean position
2705b) The periodic time of a particle moving with simple harmonic motion is directly proportional to its angular velocity
2706c) The velocity of a particle moving with simple harmonic motion is zero at the mean position
2707d) The periodic time of a particle moving with simple harmonic motion is the time taken by a particle for one complete oscillation
2708131
270965. Typewriter constitutes
2710a) machine
2711b) structure
2712c) mechanism
2713d) inversion
271466. If magnification factor is high for costant damping factor
2715a) the excitation frequecy may get resonanace or nearby the resonanace
2716b) the excitation frequecy may be higher than resonanace
2717c) the excitation frequecy may be lower than resonanace
2718d) the excitation frequecy may be 0.5 times of resonanace
271967. The natural frequency of torsional circular bar depends on
2720a) shear modulus, diameter, length and density
2721b) shear modulus, diameter and length
2722c) diameter, length and density
2723d) shear modulus,length and density
272468. The natural frequency of axial circular bar depends on
2725a) Young's modulus, diameter, length and density
2726b) diameter, length and density
2727c) Young's modulus, length and density
2728d) diameter, length and density
272969. If the circular bar gets resonanace with its longitudinal frequency
2730a) bar will deforms
2731132
2732b) bar will get angular deformation
2733c) bar will deflect
2734d) bar will get twisted
273570. What type of vibration is predomint in the beam structure?
2736a) Transverse
2737b) longitudinal
2738c) torsional
2739d) random
27401. Which of the following disciplines provides study of inertia forces arising from the combined effect of the mass and the
2741motion of the parts
2742a) theory of machines
2743b) Applied mechanics
2744c) mechanisms
2745d) kinetics
27462. The type of pair formed by two elements which are so connected that one is constrained to turn or revolve about a fixed axis of another element is known as
2747a) turning pair
2748b) rolling pair
2749c) sliding pair
2750d) spherical pair
27513. Which of the following is a lower pair
2752133
2753a) gear drive
2754b) piston and cylinder
2755c) cam and follower
2756d) belt drive
27574. The Klein's method of construction for reciprocating engine mechanism
2758a) is based on acceleration diagram
2759b) is a simplified form of instantaneous center method
2760c) utilises a quadrilateral similar to the diagram of mechanism for reciprocating engine
2761d) enables determination of Corioli's component
27625. In elliptical trammels
2763a) all four pairs are turning
2764b) three pairs turning and one pair sliding
2765c) two pairs turning and two pairs sliding
2766d) one pair turning and three pairs sliding
27676. In an ideal machine, the output as compared to input is
2768a) less
2769b) more
2770c) equal
2771d) may be less or more depending on efficiency
2772134
27737. Inertia force acts
2774a) perpendicular to the accellerating force
2775b) along the direction of accellerating force
2776c) opposite to the direction of accellerating force
2777d) in any direction w.r.t. accellerating force depending on the magnitude
27788. The Bifilar suspension method is used to determine
2779a) natural frequency of vibration
2780b) position of balancing weights
2781c) moment of inertia
2782d) centripetal acceleration
27839. According to Kennedy's theorem, if three bodies have plane motions, their instantaneous centers lie on
2784a) a triangle
2785b) a point
2786c) two lines
2787d) a straight line
278810. Which of the following conditions should be satisfied for static balancing?
2789135
27901. Dynamic forces acting on the system should be zero
27912. Couple acting on the system due to dynamic force should be zero
27923. Centrifugal forces acting on the system should be zero
27934. Couple acting on the system due to centrifugal forces should be zero
2794a) Condition 1 and condition 2
2795b) Condition 3 and condition 4
2796c) Condition 1 and condition 3
2797d) Condition 2 and condition 3
279811. In which type of vibrations, amplitude of free vibration goes on decreasing every cycle?
2799a) Free damped vibrations
2800b) Free undamped vibrations
2801c) Force damped vibrations
2802d) Force undamped vibrations
280312. What are deterministic vibrations?
2804a) Vibrations caused due to known exciting force
2805b) Vibrations caused due to unknown exciting force
2806c) Vibrations which are aperiodic in nature
2807d) Vibrations which are periodic in nature
280813. According to which method, maximum kinetic energy at mean position is equal to maximum potential energy at extreme position?
2809a) Energy method
2810b) Rayleigh's method
2811136
2812c) Equilibrium method
2813d) Newtonian method
281414. Determine natural frequency of a system, which has equivalent spring stiffness of 30000 N/m and mass of 20 kg?
2815a) 12.32 Hz
2816b) 6.16 Hz
2817c) 4.10 Hz
2818d) 8.10 Hz
281915. What is meant by phase difference or phase angle in forced vibrations?
2820a) Difference between displacement vector (xp) and velocity vector Vp
2821b) Angle in which displacement vector leads 90 degree force vector by (F0 sinωt)
2822c) Angle in which displacement vector (xp) lags force vector (F0 sinωt)
2823d) Angle in which displacement vector leads force vector by (F0 sinωt)
282416. Magnification factor is the ratio of
2825a) zero frequency deflection and amplitude of steady state vibrations
2826b) amplitude of steady state vibrations and zero frequency deflection
2827c) amplitude of unsteady state vibrations and zero frequency distribution
2828d) zero frequency distribution and amplitude of unsteady state vibrations
282917. Which of the following statements is/are true?
28301. Magnification factor is minimum at resonance
28312. The maximum value of amplification factor increases as damping factor decreases
28323. The maximum value of amplification factor increases as damping factor increases
2833137
28344. Magnification factor is maximum at resonance
2835a) Statement 1 and statement 2
2836b) Statements 1,2 and 3
2837c) Statement 2 and statement 4
2838d) Statement 2 and statement 3
283918. Simulation is a process which _________
2840a) Involves formation of a prototype
2841b) Explores behavior of a model by varying input variables
2842c) Develops geometry of an object
2843d) Develops attribiites of an object
284419. Which of the following statements is/are true?
28451. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction
28462. Shaft vibrates with maximum frequency when rotors rotate in same direction
28473. Zero node behavior is observed in rotors rotating in opposite direction
28484. All of the above
2849a) Statement 1
2850b) Statement 2
2851c) Statement 3
2852d) Statement 2 and 3
285320. Seismometer can be used to measure acceleration of any instrument only if _____
2854a) It's natural frequency is high
2855138
2856b) it generates output signal which is proportional to relative acceleration of the vibrating object
2857c) It's natural frequency is high and it generates output signal which is proportional to relative acceleration of the vibrating object
2858d) it's natural frequency is low
285921. Which type of monitoring system uses stroboscope to measure speed of the machine?
2860a) Portable condition monitoring system
2861b) Basic condition monitoring system
2862c) Computer based condition monitoring system
2863d) structural condition monitoring system
286422. Which of the following vibrometers have frequency ratio (ω/ωn) << 1?
2865a) Accelerometers
2866b) Velometers
2867c) displacement meter
2868d) optical sensor
286923. Which of the following conditions is/are to be satisfied by the seismometer for it to be used as velometer?
2870a) It's natural frequency should be large
2871b) It's natural frequency should be small
2872c) It's output signal should be proportional to relative acceleration of the vibrating body
2873d) It's output signal should be proportional to relative velocity of the vibrating body
287424. Which of the following methods can be used to reduce excitation level at the source?
2875a) Lubrication of joints
2876b) Balancing inertia forces
2877139
2878c) Lubrication of joints and Balancing inertia forces
2879d) providing dampers
288025. Which of the following is a type of untuned vibration absorber?
2881a) Houdaille damper
2882b) Torsional vibration absorber
2883c) Centrifugal pendulum absorber
2884d) viscous damper
288526. Which basic document describes general requirements for measurement and evaluation of machine vibrations using shaft measurements?
2886a) ISO – 10816-1
2887b) ISO – 7919-1
2888c) ISO – 10816-1 and ISO – 7919-1
2889d) ISO – 7901
289027. In a vibrating system, if the actual damping coefficient is 40 N/m/s and critical damping coefficient is 420 N/m/s, then logarithmic decrement is equal to
2891a) 0.2
2892b) 0.4
2893c) 0.6
2894d) 0.8
289528. The cam follower mechaism has a type of
2896140
2897a) sliding pair
2898b) rolling pair
2899c) lower pair
2900d) higher pair
290129. The balancing of a rigid rotor can be achieved by appropriately placing balancing masses in
2902a) a single plane
2903b) two planes
2904c) three planes
2905d) four planes
290630. When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
2907a) Zero
2908b) One
2909c) π/2
2910d) π
291131. In a spring controlled governor, when the controlling force ________ as the radius of rotation increases, it is said to be a stable governor.
2912a) Remains constant
2913b) Decreases
2914c) Increases
2915d) logrithmically decreases
291632. If the radius of gyration of a compound pendulum about an axis through e.g. is more, then its frequency of oscillation will be
2917141
2918a) Less
2919b) More
2920c) Same
2921d) infinite
292233. Under logarithmic decrement, the amplitude of successive vibrations are
2923a) Constant
2924b) In arithmetic progression
2925c) In geometric progression
2926d) In logarithmic progression
292734. A spring controlled governor is said to be stable if the controlling force line when produced intersects the Y-axis
2928a) At the origin
2929b) Below the origin
2930c) Above the origin
2931d) zero
293235. The dynamic friction is the friction experienced by a body, when the body
2933a) Is in motion
2934b) Is at rest
2935c) Just begins to slide over the surface of the other body
2936d) gets the constant load
293736. When the relation between the controlling force (Fc) and radius of rotation (r) for a spring controlled governor is Fc = ar + b, then the governor will be
2938a) Stable
2939b) Unstable
2940142
2941c) Isochronous
2942d) Equilibrium
294337. A watt's governor can work satisfactorily at speeds from
2944a) 60 to 80 rpm.
2945b) 80 to 100 rpm.
2946c) 100 to 200 rpm.
2947d) 200 to 300 rpm.
294838. Sensitiveness of the governor is defined as the ratio of the
2949a) Mean speed to the maximum equilibrium speed
2950b) Mean speed to the minimum equilibrium speed
2951c) Difference of the maximum and minimum equilibrium speeds to the mean speed
2952d) Sum of the maximum and minimum equilibrium speeds to the mean speed
295339. A spring controlled governor is found unstable. It can be made stable by
2954a) Increasing the spring stiffness
2955b) Decreasing the spring stiffness
2956c) Increasing the ball mass
2957d) Decreasing the ball mass
295840. Which of the following statement is correct?
2959a) The periodic time of a particle moving with simple harmonic motion is the time taken by a particle for one complete oscillation.
2960b) The periodic time of a particle moving with simple harmonic motion is directly proportional to its angular velocity.
2961c) The velocity of a particle moving with simple harmonic motion is zero at the mean position.
2962143
2963d) The acceleration of the particle moving with simple harmonic motion is maximum at the mean position.
2964Engineering Mechanics
29651. A mass m1 of 100 kg travelling with a uniform velocity of 5 m/s along a line collides with a stationary mass m2 of 1000 kg. After the collision, both the masses travel together with the
2966same velocity. The coefficient of restitution is
2967a) 0.6
2968b) 0.1
2969c) 0.01
2970d) 0
29712. An annular disc has a mass m, inner radius R and outer radius 2R. The disc rolls on a flat surface without slipping. If the velocity of the centre of mass is v, the kinetic energy of the disc is
2972a) 9/16 mv^2
2973b) 11/16 mv^2
2974c) 13/16 mv^2
2975d) 15/16 mv^2
29763. A tourist covers half of his journey by train at 60 km/h, half of the remainder by bus at 30 km/h and the rest by cycle at 10 km/h. The average of the tourist in km/h during his entire journey is
2977a) 36
2978b) 30
2979c) 24
2980d) 18
2981144
29824. A circular disc of uniform thickness 20 mm, radius 200 mm and mass 20 kg is used as a flywheel. If it rotates at 600 rpm, the kinetic energy of the flywheel in Joules is
2983a) 395
2984b) 790
2985c) 1580
2986d) 3160
29875. A solid disc of radius r rolls without slipping on the horizontal floor with angular velocity ω angular acceleration α. The magnitude of the acceleration of the point of contact on the disc is
2988a) Zero
2989b) rα
2990c) √(〖(rα)〗^2+〖〖(rω〗^2)〗^2 )
2991d) rω^2
29926. The coefficient of restitution of a perfectly plastic impact is
2993a) 0
2994b) 1
2995c) 2
2996d) infinity
2997Engineering Mechanics Winter 2015 2016
29981. Two forces of 6 and 8 act at right angles to each other, the resultant force will be
2999a) 10
3000b) 28
3001145
3002c) 41
3003d) 14
30042. The angle of projection when the range is equal to the distance through which the particle would have fallen in order to acquire a velocity equal to the velocity of projection will be
3005a) 22.5 degree
3006b) 30 degree
3007c) 45 degree
3008d) 15 degree
30093. The direction of projection for the range of a projectile to be maximum on an inclined plane having angle of inclination 30 deg to the horizontal, should be
3010a) 30 deg with horizontal
3011b) 30 deg with vertical
3012c) 45 deg with horizontal
3013d) 45 with inclined plane
30144. For perfectly elastic bodies, the value of the coefficient of restitution is
3015a) 0
3016b) 0.372
3017c) 0.5
3018d) 1
30195. A wound watch spring possesses energy in the form of
3020a) Potential energy
3021b) Kinetic energy
3022c) Spring energy
3023d) Mechanical potential energy
3024146
30256. A ball weighing 250 gm is thrown vertically upwards with a velocity of 980 cm/sec. The time that the ball will take to return back to earth would be
3026a) 1 sec
3027b) 2 sec
3028c) 3 sec
3029d) 4 sec
30307. A ball weighing 250 gm is thrown vertically upwards with a velocity of 980 cm/sec. The maximum height attained by the ball would be
3031a) 100 cm
3032b) 49 cm
3033c) 490 cm
3034d) 980 cm
30358. For the maximum range of a projectile the angle of projection should be
3036a) 22.5 deg
3037b) 30 deg
3038c) 45 deg
3039d) 60 deg
30409. A stone is thrown up from the foot of tower 50 m high with a velocity of 25 m/s and at the same time another stone is dropped from the top of tower, the two stones will cross each other after
3041a) 2 sec
3042b) 3 sec
3043c) 4 sec
3044d) 4.5 sec
3045147
304610. Identify the incorrect statement if any
3047a) The C.G. of a square is at the intersection of diagonals
3048b) The C.G. of an equilateral triangle is the intersection of medians
3049c) The C.G. of an ellipse is at the intersection of major and minor axes.
3050d) The C.G. of a semi-circle is at a distance r/2 from the centre.
305111. The C.G. of a hemisphere is from its base measured along the vertical radius r s at a distance from the base
3052a) 3R/8
3053b) 3R/4
3054c) 3Pi/4R
3055d) 4Pi/3R
305612. The C.G. of a right circular cone lies on the axis at a height (h is total height of cone) from base
3057a) h/4
3058b) h/3
3059c) 3/4 h
3060d) 3/5 h
306113. When a body moves round a fixed axis it will have
3062a) A circular motion
3063b) A rotary motion
3064c) A translatory motion
3065d) A swinging motion
3066148
306714. A ball of mass 1 kg moving with a velocity of 2 m/s collides directly with a stationary ball of mass 2 kg. If the first ball comes to rest after the impact the veocity of second ball after the impact will be
3068a) Zero
3069b) 0.5 m/sec
3070c) 1.0 m/sec
3071d) 1.5 m/sec
307215. A flywheel weighs 400 kg and has a radius of gyration of 30 cm about its axis of rotation. It is mounted on a shaft subjected to a moment of 40 kgm.If the flywheel starts from rest its speed after 3 seconds will be
3073a) 10.9 rad/sec
3074b) 19 rad/sec
3075c) 16.35 rad/sec
3076d) 3.33 rad/sec
307716. A crate weighing 40 kg rests on a cart moving with an acceleration W. The coefficient of friction between the cart and the crate is 0.25. The maximum acceleration so that the crate does not slip along the cart will be
3078a) 0.25 m/sec2
3079b) 2.45 m/sec2
3080c) 1.25 m/sec2
3081d) 4.00 m/sec2
308217. The motion of bicycle wheel is
3083a) Linear
3084b) Rotary
3085c) Translatory
3086d) Rotary as well as translatory
3087149
308818. A body weighing 500 kg falls 8 cm and strikes a 500 kg/cm spring. The deformation of the spring will be
3089a) 8 cm
3090b) 0.8 cm
3091c) 2 cm
3092d) 4 cm
309319. A body of weight W is resting at a plane inclined at 30 deg to the horizontal. It is attached to a string making an angle of 60 deg with horizontal. If the angle of friction be 30 deg the tension in the string would be
3094a) Zero
3095b) W
3096c) W/2
3097d) 2W
309820. The locus of instantaneous centre of a moving rigid body
3099a) Involute
3100b) Cycloid
3101c) Epicycloid
3102d) Centrode
310321. The resultant of a force acting on a body will be zero, if the body
3104a) Rotates
3105b) Does not rotate
3106c) Rotates with uniform acceleration
3107d) Moves along a curved path
3108150
310922. The tension in the wire rope supporting a lift moving with a uniform velocity
3110a) is more when the lift is moving down wards
3111b) is less when the lift is moving up wards
3112c) is more when the lift is moving upwards
3113d) remains constant irrespective of the lift movement
311423. A particle is of weight 8 kg. When it is allowed to fall under the force of gravity its momentum at the time t = 2 sec would be
3115a) 2 kg sec
3116b) 8 kg sec
3117c) 16 kg sec
3118d) 32 kg sec
311924. A car travelling at a speed of 60 km/hr is brakedand comes to rest 6 seconds after the brakes are applied. The minimum coefficient of friction between the wheels and the road would be
3120a) 0.107
3121b) 0.283
3122c) 0.3
3123d) 0.417
312425. If g1 and g2 are gravitational accelerations at two mountains A and B respectively, the weight of the body when transported from A to B will be multiplied by
3125a) g1
3126b) g2
3127c) g2/g1
3128d) g1/g2
3129151
313026. The work done in sliding a block of weight of 50 kg up a plane inclined at an angle of 30 deg to the horizontal so that the block is lifted through 1 m (coefficient of friction is 0.3) would be
3131a) More than 50 kg m
3132b) 50 kg m
3133c) less than 50 kg m
3134d) 15 kg m
313527. If the gravitational acceleration at any place is doubled the weight W of a body will become
3136a) W/2
3137b) 2W
3138c) 0.77W
3139d) W/0.77
314028. A stone of weight 100 kg is thrown vertically upwards by a man of height y = 1.8 m with an initial velocity of 20 m/sec. The maximum height to which it will rise would be
3141a) 10 m
3142b) 15.1 m
3143c) 20.2 m
3144d) 22.2 m
314529. A train starts from rest on a curved track of radius 800. Its speed increases uniformly and after 3 minutes it is 72 km/hr. The tangential acceleration after 2 minute would be
3146a) 1/9 m/s2
3147b) 2/9 m/s2
3148c) 1/2m/s2
3149d) 1 m/s2
3150152
315130. A wedge is used to split logs. If φ is the angle of friction between the wedge and the log, the maximum angle α of the wedge so that it will remain embedded in the log would be
3152a) φ
3153b) 1.414φ
3154c) 1.5φ
3155d) 2φ
315631. The moment of a force
3157a) occurs about a point
3158b) Measures the capacity to do useful work
3159c) Measures the ability to produce turning or twisting about an axis
3160d) Occurs only when bodies are in motion
316132. A framed structure is perfect if it contains members equal to
3162a) n-3
3163b) n-2
3164c) 2n-3
3165d) 2n-2
316633. The moment of inertia of a thin ring about an axis perpendicular to plane of ring is
3167a) Mr
3168b) 〖Mr〗^2
3169c) 〖Mr〗^2/2
3170d) 〖Mr〗^3/3
317134. The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm about the axis passing through its centre is
3172153
3173a) 33.4 cm4
3174b) 66.8 cm4
3175c) 137.5 cm4
3176d) 275 cm4
317735. If the angle of friction is zero a body will experience
3178a) Infinite friction
3179b) Zero friction
3180c) The force of friction will act normal to the plane
3181d) The force of friction will act in the direction of motion
318236. A rigid body is in equilibrium under the action of these forces when
3183a) These forces equal
3184b) The lines of action of these forces are parallel
3185c) The lines of action of these forces meet at a point
3186d) (B) and (C) above
318737. The roattion of a pulley is defined by the relation θ=2t^4-30t^(2 )+6 where θ is measured in radians and t in seconds. The values of angular velocity in radians per second after 4 seconds would be
3188a) 246
3189b) 272
3190c) 324
3191d) 446
319238. The angular acceleration of a flywheel decreases uniformly from 8 rad/sec2 to 2 rad/sec2 in 6 sec at which time its angular velocity is 42 rad/sec. The initial angular velocity was
3193a) 3 rad/sec
3194154
3195b) 6 rad/sec
3196c) 12 rad/sec
3197d) 24 rad/sec
319839. Which of the following is scalar quantity
3199a) Displacement of a particle
3200b) Area of a triangle
3201c) Acceleration of car
3202d) Velocity of a gear
320340. In the impact problems the following conditions must always be satisfied:
3204a) The total kinetic energy remains unchanged
3205b) The total linear momentum remains unchanged
3206c) The magnitude of the total linear momentum is multiplied by the coefficient of restitution
3207d) The kinetic energy of the system is reduced by a factor proportional to the coefficient of restitution
3208155
3209Engineering Mechanics
32101. Non-coplaner concurrent forces are those forces which
3211a) do not meet at one point and their lines of action do not lie on the same plane
3212b) meet at one point, but their lines of action do not lie on the same plane
3213c) meet at one point and their lines of action also lie on the same plane
3214d) do not meet at one point, but their lines of action lie on the same plane
32152. Which of the following statement is correct?
3216a) The kinetic energy of a body during impact remains constant.
3217b) The kinetic energy of a body before impact is equal to the kinetic energy of a body after impact.
3218c) The kinetic energy of a body before impact is less than the kinetic energy of a body after impact.
3219d) The kinetic energy of a body before impact is more than the kinetic energy of a body after impact.
32203. The principle of transmissibility of forces states that, when a force acts upon a body, its effect is
3221a) maximum, if it acts at the centre of gravity of the body
3222b) minimum, if it acts at the centre of gravity of the body
3223c) same at every point on its line of action
3224d) different at different points on its line of action
32254. In ideal machines, mechanical advantage is __________ velocity ratio.
3226a) less than
3227b) none of these
3228c) greater than
3229156
3230d) equal to
32315. Concurrent forces are those forces whose lines of action
3232a) meet at one point
3233b) meet on the same plane
3234c) none of these
3235d) lie on the same line
32366. The angular velocity (in rad / s) of a body rotating at N revolutions per minute is
3237a) πN/180
3238b) πN/60
3239c) 2Ï€N/60
3240d) 2Ï€N/180
32417. According to the law of moments, if a number of coplaner forces acting on a particle are in equilibrium, then
3242a) the algebraic sum of their moments about any point is equal to the moment of their resultant force about the same point.
3243b) the algebraic sum of their moments about any point in their plane is zero
3244c) their lines of action are at equal distances
3245d) their algebraic sum is zero
32468. A machine having an efficiency less than 50%, is known as
3247a) ideal machine
3248b) non-reversible machine
3249c) reversible machine
3250d) neither reversible nor non-reversible machine
3251157
32529. The centre of gravity of a semi-circle lies at a distance of __________ from its base measured along the vertical radius.
3253a) 3r/4Ï€
3254b) 4r/ 3Ï€
3255c) 3r/ 8
3256d) 8r/3
325710. The motion of a particle round a fixed axis is
3258a) rotary
3259b) translatory
3260c) circular
3261d) translatory as well as rotatry
326211. A body of weight W is required to move up on rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by(where μ = tanφ = Coefficient of friction between the plane and the body.)
3263a) P = W tan(α + φ)
3264b) P = W tanα
3265c) P = W (sinα + μcosα)
3266d) P = W (cosα + μsinα)
326712. If a number of forces are acting at a point, theirresultant will be inclined at an angle θ with the horizontal, such that
3268a) tan θ = ΣH/ΣV
3269b) tan θ = ΣVxΣV
3270c) tan θ = ΣVxΣH
3271d) tan θ = ΣV/ΣH
3272158
327313. Which of the following is a scalar quantity?
3274a) Speed
3275b) Velocity
3276c) Force
3277d) Acceleration
327814. The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction in which the force acts. This statement is known as
3279a) Newton's first law of motion
3280b) Newton's second law of motion
3281c) Newton's third law of motion
3282d) none of these
328315. The point, through which the whole weight of the body acts, irrespective of its position, is known as
3284a) moment of inertia
3285b) centre of percussion
3286c) centre of gravity
3287d) centre of mass
328816. The unit of energy in S.I. units is
3289a) dyne
3290b) kg-m
3291c) joule
3292d) watt
329317. A couple produces
3294a) translatory motion
3295159
3296b) none of the above
3297c) combined translatory and rotational motion
3298d) rotational motion
329918. A rubber ball is dropped from a height of 2 m. If there is no loss of velocity after rebounding, the ball will rise to a height of
3300a) 1m
3301b) 4m
3302c) 3m
3303d) 2m
330419. The angle of inclination of the plane at which the body begins to move down the plane, is called
3305a) angle of repose
3306b) angle of projection
3307c) angle of friction
3308d) none of these
330920. Varingon’s theorem of moments states that if a number of coplaner forces acting on a particle, then
3310a) their algebraic sum is zero
3311b) their lines of action are at equal distances
3312c) the algebraic sum of their moments about any point in their plane is zero
3313d) the algebraic sum of their moments about any point is equal to the moment of their resultant force about the same point.
331421. Whenever a force acts on a body and the body undergoes a displacement, then
3315a) none of these
3316160
3317b) body has kinetic energy of translation
3318c) power is being transmitted
3319d) work is said to be done
332022. The rate of doing work is known as
3321a) power
3322b) potential energy
3323c) kinetic energy
3324d) none of these
332523. Onejoule is equal to
3326a) 0.1 N-m
3327b) 1 N-m
3328c) 10 N-m
3329d) 100 N-m
333024. The resultant of the two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then
3331a) Q = 2R
3332b) Q = R
3333c) P = Q
3334d) none of these
333525. When the spring of a watch is wound, it will possess
3336a) kinetic energy
3337b) heat energy
3338c) electrical energy
3339161
3340d) strain energy
334126. The total energy possessed by a system of moving bodies
3342a) is minimum in the start and maximum at the end
3343b) is maximum in the start and minimum at the end
3344c) varies from point to point
3345d) is constant at every instant
334627. The static friction
3347a) is independent of the area of contact, between the two surfaces
3348b) bears a constant ratio to the normal reaction between the two surfaces
3349c) always acts in a direction, opposite to that in which the body tends to move
3350d) all of the above
335128. The forces, which meet at one point and their lines of action also lie on the same plane, are known as
3352a) non-coplaner non-concurrent forces
3353b) coplaner concurrent forces
3354c) coplaner non-concurrent forces
3355d) non-coplaner concurrent forces
335629. Which of the following are vector quantities?
3357a) all of these
3358b) Angular acceleration
3359c) Angular displacement
3360d) Angular velocity
3361162
336230. The term ‘centroid’ is
3363a) the point of suspension
3364b) the point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis
3365c) none of the above
3366d) the same as centre of gravity
336731. The centre of gravity of a quadrant of a circle lies along its central radius (r) at a distance of
3368a) 0.5r
3369b) 0.7r
3370c) 0.6r
3371d) 0.8r
337232. Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its vertex and parallel to the base, is __________ than that passing through its C.G. and parallel to the base.
3373a) seven times
3374b) five times
3375c) nine times
3376d) six times
337733. According to lami’s theorem
3378a) the three forces must be at 120° to each other
3379b) the three forces must be in equilibrium
3380c) the three forces must be equal
3381d) if the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two
3382163
338334. The matter contained in a body, is called
3384a) momentum
3385b) impulsive force
3386c) mass
3387d) weight
338835. Moment of inertia is the
3389a) second moment of area
3390b) second moment of mass
3391c) second moment of force
3392d) all of these
339336. If P is the force acting on the body, m is the mass of the body and a is the acceleration of the body, then according to Newton’s second law of motion,
3394a) P - m.a = 0
3395b) P + m.a = 0
3396c) P x m.a = 0
3397d) P/m.a = 0
339837. The coefficient of restitution for inelastic bodies is
3399a) more than one
3400b) one
3401c) between zero and one
3402d) zero
340338. The energy possessed by a body, for doing work by virtue of its position, is called
3404a) potential energy
3405164
3406b) chemical energy
3407c) kinetic energy
3408d) electrical energy
340939. A lead ball with a certain velocity is made to strike a wall, it falls down, but rubber ball of same mass and with same velocity strikes the same wall, it rebounds. Select the correct reason from the following:
3410a) both the balls undergo an equal change in momentum
3411b) the change in momentum suffered by rubber ball is more than the lead ball
3412c) the change in momentum suffered by rubber ball is less than the lead ball
3413d) none of the above
341440. A ladder is resting on a smooth ground and leaning against a rough vertical wall. The force of friction will act
3415a) away from the wall at its upper end
3416b) towards the wall at its upper and
3417c) downward at its upper end
3418d) upward at its upper end
341941. Which of the following statement is correct in connection with projectiles?
3420a) The angle, with the horizontal, at which a projectile is projected is known as angle of projection.
3421b) A path, traced by a projectile in the space, is known as trajectory.
3422c) The velocity with which a projectile is projected, is known as the velocity of projection.
3423d) all of the above
342442. The forces, whose lines of action are parallel to each other and act in the same directions, are known as
3425a) coplaner non-concurrent forces
3426165
3427b) like parallel forces
3428c) unlike parallel forces
3429d) coplaner concurrent forces
343043. A pendulum which executes one beat per second is known as
3431a) second's pendulum
3432b) compound pendulum
3433c) simple pendulum
3434d) coplaner concurrent forces
343544. The acceleration of a body sliding down an inclined surface is
3436a) g sin θ
3437b) g cos θ
3438c) g tan θ
3439d) none of these
344045. In order to completely specify angular displacement by a vector, it must fix
3441a) direction of the axis of rotation
3442b) magnitude of angular displacement
3443c) sense of angular displacement
3444d) all of these
344546. Two forces are acting at an angle of 120°. The bigger force is 40N and the resultant is perpendicular to the smaller one. The smaller force is
3446a) 40 N
3447b) 30 N
3448c) 20 N
3449166
3450d) none of these
345147. The centre of gravity a T-section 100 mm x 150 mm x 50 mm from its bottom is
3452a) 87.5mm
3453b) 75mm
3454c) 50mm
3455d) 125mm
345648. If a body is acted upon by a number of coplaner non-concurrent forces, it may
3457a) be completely at rest
3458b) rotate about itself without moving
3459c) move in any one direction rotating about itself
3460d) all of these
346149. A number of forces acting at a point will be in equilibrium, if
3462a) sumof resolved parts in the vertical direction is zero (i.e. ΣV = 0)
3463b) all the forces are equally inclined
3464c) sum of all the forces is zero
3465d) none of these
346650. A force acting on a body may
3467a) introduce internal stresses
3468b) balance the other forces acting on it
3469c) retard its motion
3470d) all of the above.
347151. Which is the correct statement about law of polygon of forces ?
3472167
3473a) if any number of forces acting at a point can be represented by the sidesof a polygon taken in order, then the forces are in equilibrium
3474b) if any number of forces acting at a point can be represented in direction and magnitude by the sides of a polygon, then the forces are in equilibrium
3475c) if a polygon representing forces acting at a point is closed then forces are in equilibrium
3476d) none of the above.
347752. If a number of forces act simultaneously on
3478a particle, it is possible
3479a) not to replace them by a single force
3480b) to replace them by a single force
3481c) (c) to replace them by a single force through C.G.
3482d) to replace them by a couple
348353. Which of the following do not have identical dimensions ?
3484a) Momentum and impulse
3485b) Torque and energy
3486c) Torque and work
3487d) None of the above
348854. The weight of a body is due to
3489a) centripetal force of earth
3490b) gravitational pull exerted by the earth
3491c) forces experienced by body in atmosphere
3492d) gravitational force of attraction towards the center of the earth.
349355.
3494168
3495Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the ball with velocity v is made to struck the second ball. Both the balls after impact will move with a velocity
3496a) v
3497b) v/2
3498c) v/4
3499d) v/8
350056. The range of projectile on a downward inclined plane is __________ the range on upward inclined plane for the same velocity of projection and angle of projection.
3501a) less than
3502b) more than
3503c) equal to
3504d) All of these
350557.
3506If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is
3507a) 30°
3508b) 60°
3509c) 90°
3510d) 120°
351158. Moment of inertia of a circular section about an axis perpendicular to the section is
3512a) πd3/16
3513b) πd3/32
3514c) πd4/32
3515169
3516d) πd4/64
351759. Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its C.G. and parallel to the base, is
3518a) bh3/4
3519b) bh3/8
3520c) bh3/12
3521d) bh3/36
352260. The algebraic sum of the resolved parts of a number of forces in a given direction is equal to the resolved part of their resultant in the same direction. This is as per the principle of
3523a) forces
3524b) independence of forces
3525c) balance of force
3526d) resolution of forces.
352761. When trying to turn a key into a lock, following is applied
3528a) coplanar force
3529b) non-coplanar forces
3530c) moment
3531d) couple
353262. A number of forces acting at a point will be in equilibrium if
3533a) their total sum is zero
3534b) two resolved parts in two directions at right angles are equal
3535c) sum of resolved parts in any two per-pendicular directions are both zero
3536d) none of the above.
3537170
353863. Two non-collinear parallel equal forces acting in opposite direction
3539a) balance each other
3540b) constitute a moment
3541c) constitute a couple
3542d) constitute a moment of couple
354364. If a rigid body is in equilibrium under the action of three forces, then
3544a) these forces are equal
3545b) the lines of action of these forces meet in a point
3546c) the lines of action of these forces are parallel
3547d) none of the above.
354865. D' Alembert's principle is used for
3549a) reducing the problem of kinetics to equivalent statics problem
3550b) determining stresses in the truss
3551c) stability of floating bodies
3552d) solving kinematic problems
355366. A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if
3554a) the floor is smooth, the wall is rough
3555b) the floor is rough, the wall is smooth
3556c) the floor and wall both are smooth surfaces
3557d) will be in equilibrium under all conditions.
355867. Two coplanar couples having equal and opposite moments
3559a) balance each other
3560b) produce a couple and an unbalanced force
3561171
3562c) are equivalent
3563d) can not balance each other.
356468. The product of either force of couple with the arm of the couple is called
3565a) resultant couple
3566b) moment of the forces
3567c) moment of the couple
3568d) none of the above
356969. Center of gravity of a solid cone lies on the axis at the height
3570a) one-fourth of the total height above base
3571b) one-third of the total height above base
3572c) three-eighth of the total height above the base
3573d) none of the above.
357470. The coefficient of friction depends on
3575a) area of contact
3576b) nature of surface
3577c) strength of surfaces
3578d) all of the above
357971. The ratio of limiting friction and normal reaction is known as
3580a) coefficient of friction
3581b) angle of friction
3582c) angle of repose
3583d) friction resistance.
3584172
358572. Pick up wrong statement about friction force for dry surfaces. Friction force is
3586a) proportional to normal load between the surfaces
3587b) dependent on the materials of contact surface
3588c) proportional to velocity of sliding
3589d) independent of the area of contact surfaces
359073. Coulomb friction is the friction between
3591a) bodies having relative motion
3592b) two dry surfaces
3593c) two lubricated surfaces
3594d) solids and liquids
359574. Dynamic friction as compared to static friction is
3596a) same
3597b) more
3598c) less
3599d) may be less of more depending on nature of surfaces and velocity
360075. A single force and a couple acting in the
3601same plane upon a rigid body
3602a) balance each other
3603b) cannot balance each other
3604c) produce moment of a couple
3605d) none of the above.
360676. The maximum frictional force which comes into play when a body just begins to slide over another surface is called
3607173
3608a) limiting friction
3609b) sliding friction
3610c) rolling friction
3611d) kinematic friction
361277. A body moves, from rest with a constant acceleration of 5 m per sec. The distance covered in 5 sec is most nearly
3613a) 38 m
3614b) 62.5 m
3615c) 96 m
3616d) kinematic friction
361778. A flywheel on a motor goes from rest to 1000 rpm in 6 sec. The number of revolutions made is nearly equal to
3618a) 25
3619b) 50
3620c) 100
3621d) 250
362279. A boat is traveling along a circular path having a radius of 20 m. Determine the magnitude of the boat's acceleration if at a given instant the boat's speed is v = 5 m/s and the rate of increase in speed is v = 2 m/s2.
3623a) a = 2.00 m/s2
3624b) a = 2.36 m/s2
3625c) a = 1.25 m/s2
3626d) a = 12.50 m/s2
3627174
362880. A train travels along a horizontal circular curve that has a radius of 200 m. If the speed of the train is uniformly increased from 30 km/h to 45 km/h in 5 s, determine the magnitude of the acceleration at the instant the speed of the train is 40 km/h.
3629a) a = 0.617 m/s2
3630b) a = 1.037 m/s2
3631c) a = 1.451 m/s2
3632d) a = 0.833 m/s2
3633175
3634Engineering Thermodynamics
36351. A mono-atomic ideal gas (Ƴ = 1.67,molecular weight = 40) is compressed adiabatically from 0.1 MPa, 300 K to 0.2 MPa. The universal gas constant is 8.314 kJ/molK. The work of compression of the gas (in kJ/kg) is
3636a) 29.7
3637b) 19.9
3638c) 13.3
3639d) zero
36402. An irreversible heat engine extracts heat from a high temperature source at a rate of 100 kW and rejects heat to a sink at a rate of 50 kW. The entire work output of the heat engine is used to drive a reversible heat pump operating between a set of independent isothermal heat reservoirs at 17°C and 75°C. The rate (in kW) at which the heat pump delivers heat to its high temperature sink is
3641a) 5o
3642b) 250
3643c) 300
3644d) 360
36453. A gas expands in a frictionless piston-cylinder arrangement. The expansion process is very slow and is resisted by an ambient pressure of the 100 kPa. During the expansion process, the pressure of the system (gas) remains consant at 300 kPa. The change in volume of he gas is 0.01 m3. The maximum amount of work that could be utilized from the above process is
3646a) zero
3647b) 1 kJ
3648c) 2 kJ
3649d) 3 kJ
36504. A 100 W electirc bulb was swithed on in a 2.5 m x 3 m x 3 m size thermally insulated room having a temperature of 20°C. The room temperature at the end of 24 h will be
3651176
3652a) 321°C
3653b) 338°C
3654c) 450°C
3655d) 470°C
36565. A reversible thermodynamic cycle containing only three processes and producing work is to be constructed. The constrains are (a) there must be one isothermal process, (b) there must be one isentropic process, (c) the maximum and minimum cycle pressures and clearance volume are fixed and (d) polytropic processes are not allowed. Then the number of possible cycles is/are
3657a) 1
3658b) 2
3659c) 3
3660d) 4
36616. Nitrogen gas (molecular weight=28) is enclosed in a cylinder by a piston, at the initial conditions of 2 bar, 298 K and 1 m3. In a particular process, the gas slowly expands under isothermal condition, untill the volume becomes 2 m3. Heat exchange occurs with the atmosphere at 298K during this process. the work interaction for the nitrogen gas is
3662a) 200 kJ
3663b) 138.6 kJ
3664c) 2 kJ
3665d) -200 kJ
36667. For a giveb set of operating pressure limits of a Rankine cycle, the highest efficiency occurs for
3667a) saturated cycle
3668b) superheated cycle
3669c) reheat cycle
3670d) regenerative cycle
3671177
36728. An Otto cycle operates with volumes of 40 cm3 and 400 cm3 at Top Dead Centre and Bottom Dead Centre respectively. If the power output is 100 kW, what is the heat input in kJ/s?
3673a) 166
3674b) 145
3675c) 110
3676d) 93
36779. A football was inflated to a gauge pressure of 1 bar when the ambient temperature was 15°C. When the game started next day, the air temperature at the stadium was 5°C. Assume that the volume of the football remains constant at 2500 cm3,the amount of heat lost by the air in the football and the gauge pressure of air in the football at the stadium respectively equal to
3678a) 30.6 J, 1.94 bar
3679b) 21.8 J, 0.93 bar
3680c) 61.1 J, 1.94 bar
3681d) 43.7 J, 0.93 bar
368210. A solar collector receiving solar radiation at the rate of 0.6 kW/m2 transforms it to the internal energy of a fluid at an overall efficiency of 50%. The fluid heated to 350 K is used to run a heat engine which rejects heat at 313 K. If the heat engine is to deliver 2.5 kW power, the minimum area of the solar collector required would be
3683a) 8.33 m2
3684b) 16.66 m2
3685c) 39.68 m2
3686d) 79.36 m2
3687178
3688Engineering Thermodynamics
36891. Which of the following temperature scales doesn’t have negative numbers?
3690a) Celsius
3691b) Kelvin
3692c) Fahrenheit
3693d) Galileo
36942. Work done in a free expansion process is
3695a) Zero
3696b) Positive
3697c) Negative
3698d) Maximum
36993. Which of the following could NOT be used to indicate a temperature change? A change in:
3700a) color of a metal rod
3701b) length of a liquid column
3702c) electrical resistance
3703d) mass of one mole of gas at constant pressure
37044. An electric fan in a closed room is switched on. The room will get
3705179
3706a) Cooler
3707b) warmer
3708c) stays the same
3709d) cool down or get warmer depending upon the atmospheric conditions
37105. The property of a system that does not change when the system is undergoing adiabatic process
3711a) Pressure
3712b) Temperature
3713c) Volume
3714d) Quantity of Heat
37156. If the system undergoes contraction in volume then work done by the system is
3716a) Positive
3717b) Negative
3718c) neither positive nor negative
3719d) work done is zero
37207. For the expression ∫pdv to represent the work, which of the following conditions should apply?
3721a) The system is closed one and process takes place in non-flow system
3722b) The process is non-quasi static
3723c) The boundary of the system should not move in order that work may be transferred
3724d) If the system is open one, it should be non-reversible
37258. Ice kept in a well insulated thermo flask is an example of which system?
3726a) Closed system
3727b) Isolated systems
3728180
3729c) Open system
3730d) Equilibrium system
37319. A heat engine takes in some amount of thermal energy and performs 50 J of work in each cycle and rejects 150 J of energy. What is its efficiency?
3732a) 500 %
3733b) 400 %
3734c) 25 %
3735d) 20 %
373610. A rigid container holds an ideal gas (Cv = 0.75 kJ/(kgK) ). The container is cooled from 110℃ to 20℃. Find the specific heat transfer (kJ/kg) for the process
3737a) 67.5 kJ/ kg
3738b) – 67.5 kJ / kg
3739c) -96 kJ/kg
3740d) 96 kJ/kg
374111. A thermally insulating container has a membrane separating the container into two equal parts. In one part is a vacuum. In the other part is an ideal gas of temperature T and internal energy U. The membrane is punctured and the gas rushes into the region which was a vacuum. After the system has returned to equilibrium, which of the following is NOT true for the gas?
3742a) The temperature of the gas is changed
3743b) No work is done by the gas on the surroundings
3744c) There is no heat exchanged by the gas with the surroundings
3745d) There is no entropy change of the system
374612. Match items in List-I (Process) with those in List-II (Characteristic) and select the correct answer using the codes given below the lists:
3747181
3748List-I List-II
3749A. Throttling process 1. No work done
3750B. Adiabatic process 2. No heat transfer
3751C. Free expansion 3. Constant internal energy
3752D. Isothermal process 4. Constant enthalpy
3753a) A B C D
37544 2 1 3
3755b) A B C D
37561 2 4 3
3757c) A B C D
37584 3 1 2
3759d) A B C D
37601 3 4 2
376113. In thermodynamics it is very important to state any assumptions at the beginning of a problem. If you are asked to find the work of a cycle of a piston and cylinder, which of the following would you assume?
3762a) Work only occurs across the boundary
3763b) Changes in kinetic energy and potential energy are negligible
3764c) It is a closed system
3765d) all of the choices
376614. Think about how a refrigerator works and the system of the refrigerator and the area outside of the refrigerator at ambient temperature. Is the high temperature the body refrigerator or the ambient air around the refrigerator?
3767a) Not enough information to answer
3768b) Provided the refrigerator is working, the refrigerator is the higher temperature body
3769182
3770c) Provided the refrigerator is working, the area around the refrigerator is the higher temperature body
3771d) Provided the refrigerator is working, the bodies are of the same temperature
377215. One kg of steam at 1.01325 bar has a saturation temperature of ___________
3773a) 273 K
3774b) 273°C
3775c) 100°C
3776d) 100 K
377716. A rigid vessel contains a pure substance and it passes through the critical state on heating only if the initial state is
3778a) subcooled water
3779b) wet
3780c) dry
3781d) superheated
378217. When saturation pressure of vapour increases which one of the following statements is correct?
3783a) Saturation temperature decreases
3784b) Enthalpy of evaporation increases
3785c) Enthalpy of evaporation decreases
3786d) specific volume remains constant
378718. Increase in entropy of a system represents
3788a) Increase in availability of energy
3789b) increase in temperature
3790c) decrease in pressure
3791183
3792d) degradation of energy
379319. The temperature of water flowing through the turbine increases from 25°C to 27°C due to friction. If there is no heat transfer, determine the change of entropy of water.
3794a) 2.8 J/kgK
3795b) 28J/kgK
3796c) -2.8kJ/kgK
3797d) -28kJ/kgK
379820. A paddle wheel fitted with a 300 W motor is used to stir water in a large container. The water in the container is maintained at 300 K and if the motor runs for 2 hours, determine the change in entropy of water.
3799a) 7200 J/K
3800b) -7200 J/K
3801c) 0
3802d) 72 J/K
380321. A system of 100 kg mass undergoes a process in which its specific entropy increases from 0.3 kJ/kgK to 0.4 kJ/kgK. At the same time, the entropy of the surroundings decreases from 80 kJ/K to 75 kJ/K. Determine the process.
3804a) Reversible and isothermal
3805b) Irreversible
3806c) Reversible
3807d) Impossible
380822. When pressure is raised in an isentropic process, the enthalpy of the substance
3809a) Remains same
3810b) Increases
3811c) decreases
3812184
3813d) First increases and then decreases
381423. The dryness fraction at the end of expansion of a Reheat cycle operating under the same temperature limits has
3815a) Same as that of Rankine cycle
3816b) More than that of Rankine cycle
3817c) Less than that of Rankine cycle
3818d) Not able to correlate with provided data.
381924. Which one of the following thermodynamic relations is incorrect
3820a) T.dS = du + p.dv
3821b) T.dS = dh + v.dp
3822c) dH = T.dS + v.dp
3823d) dG = Vdp − S.dT
382425. Which one of the following is the extensive property of a thermodynamic system?
3825a) Volume
3826b) Pressure
3827c) Temperature
3828d) Density
382926. The sequence of events that eventually returns the working fluid to its original state is known as
3830a) process
3831b) cycle
3832c) path
3833d) property
3834185
383527. If C is the number of components and φ is the number of phases in a system, the number of independent intensive properties required to specify the state of the system
3836a) F=C-φ-2
3837b) F=C+φ+2
3838c) F=C-φ+2
3839d) F=C+φ-2
384028. Does a heat engine that has a thermal efficiency of 100 percent necessarily violate?
3841a) The first law
3842b) The second law
3843c) Both first law and second law
3844d) neither first nor second law
384529. Specific internal energy of an ideal gas depends on ________________ of the gas.
3846a) pressure
3847b) volume
3848c) mass
3849d) temperature
385030. A control mass refers to a ____________ system
3851a) open
3852b) closed
3853c) isolated
3854d) adiabatic
385531. Which one of the following is the extensive property of a thermodynamic system?
3856a) Enthalpy
3857186
3858b) Pressure
3859c) Temperature
3860d) Density
386132. In a reversible heat engine operating between source and sink temperatures T1 and T2 respectively and surrounded by ambient temperature (T0), the maximum work done is obtained when T2 is equal to
3862a) T2 = T1
3863b) T2 = T1/2
3864c) T2 = T0
3865d) T2=2T0
386633. Which of the following statement is true:
3867a) Heat can be completely converted into work.
3868b) Entropy of the universe is always constant.
3869c) The energy of the universe keeps on increasing
3870d) All work can be converted into heat.
387134. The change in entropy during a process is zero when
3872a) Reverse and adiabatic.
3873b) When it is reversible
3874c) When there is no heat transfer
3875d) All of these
387635. The rate of exergy loss is directly proportional to
3877a) Entropy generation
3878b) Increase in energy
3879c) Leads to increase in irreversibility
3880187
3881d) efficiency
388236. The effect of increase in mean temperature of heat addition in an ideal Rankine cycle leads to
3883a) decrease in efficiency of the cycle
3884b) increase in efficiency of the cycle
3885c) does not affect the efficiency of the cycle
3886d) first increases and then decreases the efficiency of the cycle.
388737. A saturation state is a state from which a change of phase may occur without
3888a) change in temperature
3889b) change in pressure
3890c) change in temperature and pressure
3891d) volume
389238. Which of the following curve has a negative slope for water as working fluid in the P-T phase diagram
3893a) Fusion curve
3894b) evaporation curve
3895c) triple point line
3896d) sublimation curve.
389739. The work output of a Reheat cycle operating under the same temperature limits is:
3898a) Same as that of Rankine cycle
3899b) Greater than that of Rankine cycle
3900c) Lesser than that of Ranking cycle
3901d) Not able to correlate with provided data.
3902188
390340. Which of the following statements about absolute zero temperature is true?
3904a) At absolute zero all translational motion of the particles ceases.
3905b) At absolute zero all rotational motion of the particles ceases.
3906c) Absolute zero is defined at −273.15°C.
3907d) All the above.
390841. What mass of He gas occupies 8.5 liters at 0°C and 1 atmosphere? (The molar mass of He = 4.00 g/mol.)
3909a) 10.5 g
3910b) 1.52 g
3911c) 0.38 g
3912d) 2.6 g
391342. A gas has a density X at standard temperature and pressure. What is the new density when the absolute temperature is doubled and the pressure increased by a factor of 3?
3914a) (2/3)X
3915b) (4/3)X
3916c) (3/2)X
3917d) (3/4)X
391843. A rigid container of air is at atmospheric pressure and 27ºC. To double the pressure in the container, heat it to
3919a) 54ºC
3920b) 300ºC
3921c) 327ºC
3922d) 600ºC
3923189
392444. If a mass of oxygen gas occupies a volume of 8 L at standard temperature and pressure, what is the change in the volume if the temperature is reduced by one half and the
3925pressure is doubled?
3926a) It increases to 12 L.
3927b) It decreases to 6 L.
3928c) It decreases to 2 L.
3929d) It increases to 24 L.
393045. If the pressure and volume of an ideal gas are both reduced to half their original value, the absolute temperature of the gas is
3931a) unchanged.
3932b) increased by a factor of 4.
3933c) doubled.
3934d) decreased by a factor of 4.
393546. The relationship between the pressure and the volume of a gas expressed by Boyle's law holds true
3936a) for some gases under any conditions.
3937b) for all gases under any conditions.
3938c) if the container of the gas can expand with increasing pressure.
3939d) if the temperature is constant.
394047. The air around us has 78% nitrogen and 21% oxygen. If the pressure is 1 atm, the
3941pressure due to oxygen is
3942a) 0.21 atm
3943b) 0.78 atm
3944c) 1 atm
3945d) 0.67 atm
3946190
394748. An ideal gas whose original temperature and volume are 27ºC and 0.283 m3 undergoes an isobaric expansion. If the final temperature is 87ºC, then the final volume is approximately
3948a) 0.0340 m3
3949b) 0.0552 m3
3950c) 0.170 m3
3951d) 0.340 m3
395249. To raise the temperature of a 2.0-kg piece of metal from 20º to 100ºC, 61.8 kJ of heat is added. What is the specific heat of this metal?
3953a) 0.39 kJ/kgK
3954b) 1.2 kJ/kgK
3955c) 0.31 kJ/kgK
3956d) 0.77 kJ/kgK
395750. A 2.0-kg mass of iron (specific heat = 0.12 kcal/kg°C) at a temperature of 430°C is dropped into 0.4 kg of ice and 0.4 kg of water both at 0°C. With no heat losses to the surroundings, the equilibrium temperature of the mixture is approximately
3958a) 0°C
3959b) 100°C
3960c) 23°C
3961d) 69°C
396251. On a hot summer day, water collects on the outside of a glass of ice lemonade. The water comes from
3963a) inside the glass since glass is porous.
3964b) the condensation of the water vapor due the fact that the glass is much colder than
3965the air.
3966c) the straw you use to drink your lemonade.
3967191
3968d) the mixture of water and lemonade.
396952. An ideal gas undergoes a cyclic process in which total (positive) work W is done by the gas. What total heat is added to the gas in one cycle?
3970a) W
3971b) - W
3972c) zero
3973d) 2W
397453. The pressure of a gas in an isobaric expansion remains constant. In such an expansion,
3975a) no work is done.
3976b) work is done by the gas.
3977c) work is done on the gas.
3978d) work is or is not done depending on whether the temperature of the gas changes.
397954. The change in the entropy of the universe due to an operating Carnot engine
3980a) is zero.
3981b) must be positive
3982c) must be negative
3983d) is meaningless to consider, because a Carnot engine has no connection to entropy
398455. One mole of an ideal gas undergoes a reversible isothermal expansion from a volume of 1 L to a volume of 2 L. The change in entropy of the gas in terms of the universal gas constant R is
3985a) R/2
3986b) 2R
3987c) R ln(2)
3988d) R ln(½)
3989192
399056. The thermal efficiency of theoretical Otto cycle
3991a) increases with increase in compression ratio
3992b) increases with increase in isentropic index γ
3993c) does not depend upon the pressure ratio
3994d) follows all the above.
399557. With the increase in pressure ratio thermal efficiency of a simple gas turbine plant with fixed turbine inlet temperature
3996a) decreases
3997b) increases
3998c) first increases and then decreases
3999d) first decreases and then increases.
400058. For same compression ratio
4001a) thermal efficiency of Otto cycle is greater than that of Diesel cycle
4002b) thermal efficiency of Otto cycle is less than that of Diesel cycle
4003c) thermal efficiency of Otto cycle is same as that for Diesel cycle
4004d) thermal efficiency of Otto cycle cannot be predicted
400559. The work output of theoretical Otto cycle
4006a) increases with increase in compression ratio
4007b) increases with increase in pressure ratio
4008c) increases with increase in adiabatic index γ
4009d) follows all the above.
401060. In Rankine cycle the work output from the turbine is given by
4011193
4012a) change of internal energy between inlet and outlet
4013b) change of enthalpy between inlet and outlet
4014c) change of entropy between inlet and outlet
4015d) change of temperature between inlet and outlet.
401661. Thermodynamic work is the product of
4017a) Two intensive properties
4018b) two extensive properties
4019c) an intensive property and change in an extensive property
4020d) an extensive property and change in an intensive property
402162. If the thermal efficiency of a Carnot heat engine working between two temperature reservoirs is 1/3, then COP of a Carnot refrigerator is given by
4022a) 3
4023b) 1/2
4024c) 2
4025d) 4
402663. For the same compression ratio, the efficiency of diesel cycle as compared to otto cycle is
4027a) less
4028b) more
4029c) same
4030d) equal
403164. A cycle consisting of two reversible isothermal processes and two reversible isobaric processes is known as
4032a) Otto cycle
4033b) Ericsson cycle
4034194
4035c) Stirling cycle
4036d) Brayton cycle
403765. A cycle consisting of two reversible isothermal processes and two reversible isochoric processes is known as
4038a) Otto cycle
4039b) Ericsson cycle
4040c) Stirling cycle
4041d) Brayton cycle
404266. A chemical fuel is a substance which releases____________on combustion.
4043a) chemical energy
4044b) heat energy
4045c) sound energy
4046d) magnetic energy.
404767. For each mole of oxygen, number of moles of nitrogen required for complete combustion of carbon are
4048a) 20/21
4049b) 2/21
4050c) 77/21
4051d) 79/21
405268. An analysis which includes the steam in the exhaust is called
4053a) dry analysis
4054b) wet analysis
4055c) dry and wet analysis
4056d) flue gas analysis
4057195
405869. The Orsat apparatus gives
4059a) volumetric analysis of the dry products of combustion
4060b) gravimetric analysis of the dry products of combustion
4061c) gravimetric analysis of products of combustion including H2O
4062d) volumetric analysis of products of combustion including H2O.
406370. Bomb calorimeter is used to find the calorific value of ___________ fuels.
4064a) solid
4065b) gaseous
4066c) solid and gaseous
4067d) solid, liqiud and gaseous
406871. When the fuel is burned and the water appears in the vapour phase, the heating value of fuel is called
4069a) enthalpy of formation
4070b) lower heating value
4071c) higher heating value
4072d) enthalpy of fusion
407372. When the fuel is burned and water is released in the liquid phase, the heating value of fuel is called
4074a) higher heating value
4075b) lower heating value
4076c) enthalpy of formation
4077d) enthalpy of fusion
407873. In the Orsat apparatus KOH solution is used to absorb
4079196
4080a) carbon monoxide
4081b) carbon dioxide
4082c) oxygen
4083d) nitrogen
408474. Enthalpy of formation is defined as enthalpy of compounds at
4085a) 25°C and 10 atmospheres
4086b) 25°C and 1 atmosphere
4087c) 0°C and 1 atmosphere
4088d) 100°C and 1 atmosphere.
408975. Moisture, ash content, volatile matter and fixed carbon are measured for coal as part of
4090a) Proximate analysis
4091b) Ultimate analysis
4092c) Proximate and utlimate analysis
4093d) wet analysis
409476. For the same compression ratio and heat input, the cycles in decreasing order of thermal efficiency are
4095a) Otto, Dual, Diesel
4096b) Diesel, Otto, Dual
4097c) Dual,Diesel, Otto
4098d) Otto, Diesel, Dual
409977. The triple point of water is
4100a) 54.35 K
4101b) 13.84 K
4102197
4103c) 216.55 K
4104d) 273.16 K
410578. Which of the following statements is not true with respect to Mollier diagram
4106a) the inclination of constant pressure lines equals the absolute temperature
4107b) the constant pressure lines bend slightly downward in the heated region
4108c) the expansion process through a turbine is represented by a vertical line parallel to the ordinate
4109d) the diagram helps to readly find out the total heat content of a steam of specified pressure and quality
411079. In which process, a solid changes directly to the gaseous form without ever being a liquid
4111a) condensation
4112b) evaporation
4113c) sublimation
4114d) crystalisation
411580. which of the following parameters remains constant during superheating of steam?
4116a) temperature
4117b) pressure
4118c) enthalpy
4119d) internal energy
412081. The enthalpy of vaporisation is minimum at
4121a) absolute zero
4122b) 373.16 K
4123c) critical temperature
4124d) triple point
4125198
412682. The heat absorbed by water at its saturation temperature to get converted into dry steam at the same temperture is called as
4127a) sensible heat
4128b) specific heat
4129c) latent heat
4130d) total heat
413183. Which form of the vapour has a behaviour close to that of a gas?
4132a) wet vapour
4133b) dry and saturated
4134c) wet and dry vapour
4135d) superheated vapour
413684. The internal energy of a perfect gas does not change during
4137a) adiabatic process
4138b) isibaric process
4139c) isothermal process
4140d) isochoric process
414185. The characteristic gas equation pv = mRT is essentially valid for a
4142a) real gas
4143b) perfect gas
4144c) monoatomic gas
4145d) mixture of gases
414686. For any natural process, the entropy change would be
4147199
4148a) zero
4149b) positive
4150c) negative
4151d) unpredictable
415287. For obtaining maximum work in the act of a gas expanding in a closed system, the expansion process must takes place at
4153a) constant temperature
4154b) constant pressure
4155c) constant entropy
4156d) constant enthalpy
415788. Which of the following is not a feature of the free expansion process?
4158a) irreversible process
4159b) non-quasistatic process
4160c) there is transfer of energy to the system
4161d) pressure and volume are not related through the equation of state
416289. Work output from a system is at the expense of internal energy in a non flow process carried out
4163a) at constant pressure
4164b) at constant volume
4165c) adiabatically
4166d) polytropically
416790. All of the following statements are true for a quasi-static process except
4168a) proceeds very slowly
4169b) can proceed in either direction
4170200
4171c) need not be a reversible process
4172d) occurs when the driving force is finite but very small
417391. Zeroth law of thermodynamics forms the basis of ______________ measurement
4174a) pressure
4175b) heat exchange
4176c) temperature
4177d) work
417892. Which does not constitute the theoritical cycle for the working of a practical I.C engine?
4179a) Otto cycle
4180b) Diesel cycle
4181c) Dual cycle
4182d) Ericsson cycle
418393. Steam coming out of the whistle of a pressure cooker is most likely to be
4184a) wet vapour
4185b) dry and saturated vapour
4186c) superheated vapour
4187d) supercritical
418894. Which of the following processes is not associated with Diesel cycle?
4189a) constant volume
4190b) constant pressure
4191c) isothermal
4192d) adiabatic
4193201
419495. For successful working of throttling calorimeter to determine the value of dryness fraction of steam, the steam after throttling must be in
4195a) wet steam
4196b) Dry and saturated steam
4197c) superheated steam
4198d) saturated liquid
419996. Joule Thomson expansion is
4200a) isochoric process
4201b) isobaric process
4202c) isentropic process
4203d) isenthalpic process
420497. When wet steam flows through a throttle valve and remains wet at exit, its
4205a) quality increases
4206b) quality decreases
4207c) quality remains constant
4208d) quality can not be determined. Insuffient data
420998. Three moles of an ideal gas are compressed to half the initial volume at a constant temperature of 300k. The work done in the process is
4210a) 5188 J
4211b) 2500 J
4212c) -2500 J
4213d) -5188 J
4214202
421599. In a reversible isothermal expansion process, the fluid expands from 10 bar and 2 m3 to 2 bar and 10 m3. During the process the heat supplied is at the rate of 100 kW. What is the rate of work done during the process?
4216a) 20 kW
4217b) 80 kW
4218c) 100 kW
4219d) 35 kW
4220100. The entropy of a mixture of pure gases is the sum of the entropies of constituents evaluated at
4221a) temperature and pressure for the mixture
4222b) temperature of the mixture and the partical pressure of the constituents
4223c) temperature and volume of the mixture
4224d) pressure and volume of the mixture
4225101. Which one of the following relationships defines Gibb's free energy G?
4226a) G=H + TS
4227b) G=H-TS
4228c) G= U+ TS
4229d) G= U-TS
4230102. Which one of the following is correct?
4231When a real gas undergoes Joule-Thomson expansion, the temperature
4232a) may remain constant.
4233b) always increases.
4234c) may increase or decrease
4235d) always decreases.
4236203
4237103. The throttling of certain gasses may be used for getting the refrigeration effect. What is the value of Joule – Thomson coefficient (μ) for such a throttling process?
4238a) μ = 0
4239b) μ = 1
4240c) μ < 1
4241d) μ > 1
4242104. A gas having a negative Joule-Thompson coefficient (μ< 0), when throttled, will
4243a) become cooler
4244b) become warmer
4245c) remain at the same temperature
4246d) either be cooler or warmer depending on the type of gas
4247105. For a reversible power cycle, the operating temperature limits are 800 K and 300 K. It takes 400kJ of heat. The unavailable work will be
4248a) 250 kJ
4249b) 150 kJ
4250c) 120 kJ
4251d) 100 kJ
4252106. In which one of the following situations the entropy change will be negative
4253a) Air expands isothermally from 6 bars to 3 bars
4254b) Air is compressed to half the volume at constant pressure
4255c) Heat is supplied to air at constant volume till the pressure becomes three folds
4256d) Air expands isentropic ally from 6 bars to 3 bars
4257204
4258107. A system of 100 kg mass undergoes a process in which its specific entropy increases from 0.35 kJ/kg-K to 0.45 kJ/kg-K. At the same time, the entropy of the surroundings decreases from 80 kJ/K to 75 kJ/K. The process is:
4259a) Reversible and isothermal
4260b) Irreversible
4261c) Reversible
4262d) Impossible
4263108. In the T-S diagram shown in the figure, which one of the following is represented by the area under the curve? <img src="New Picture (4).png" alt="New Picture (4).png" title="New Picture (4)" width="215" height="207"></img>
4264a) Total work done during the process
4265b) Total heat absorbed during the process
4266c) Total heat rejected during the process
4267d) Degree of irreversibility
4268109. Two ideal heat engine cycles are represented in the given figure.<img src="pv.png" alt="pv.png" title="pv" width="210" height="142"></img> Assume VQ =QR, PQ = QS and UP =PR =RT. If the work interaction for the rectangular cycle (WVUR) is
426948 Nm, then the work interaction for the other
4270cycle PST is
4271a) 12Nm
4272b) 18 Nm
4273c) 24 Nm
4274d) 36 Nm
4275205
42761. The available energy is
4277a) high grade energy
4278b) portion of energy as useful work
4279c) theoritical maximum amount of work
4280d) low grade energy
42812. To improve the work capacity of energy transfer as heat from high temperature to low temperature,
4282a) lower temperature should be lowerd, keeping the temperature difference same
4283b) higher temperature should be increased keeping the difference same
4284c) temperature difference should be increased
4285d) temperature difference should be decreased
42863. The degradation of energy is responsible for
4287a) entropy generation within the system
4288b) decrease of entropy within the system
4289c) maximum work done by the system
4290d) minimum work done by the system
42914. Maxwell's thermodynamic relations are valid for
4292a) all process
4293b) a closed system
4294c) a thermodynamic system in equilibrium
4295d) an open system
42965. The mean effective pressure of an engine is defined as
4297206
4298a) work done/stroke volume
4299b) work done per cycle/cylinder volume
4300c) work done per cycle/stroke volume
4301d) work done per kg/stroke volume
43026. The efficiency of standard Otto cycle depends on
4303a) pressure ratio in the cycle
4304b) temperature ratio in the cycle
4305c) compression ratio in the cycle
4306d) mean effective pressure
43077. The efficiency of standard Diesel cycle depends on
4308a) cut-off ratio in the cycle
4309b) compression ratio in the cycle
4310c) cut-off ratio and compression ratio
4311d) mean effective pressure
43128. Which process is included in air standard Diesel cycle?
4313a) Polytropic compression
4314b) Isochoric heat addition
4315c) Isobaric heat addition
4316d) Isochoric and isobaric heat addition
43179. Which one of the following is part of air standard dual cycle?
4318a) Polytropic compression
4319b) Isochoric heat addition
4320c) Isobaric heat addition
4321207
4322d) Isochoric and isobaric heat addition
432310. Which one of the following is part of air standard Braytion cycle?
4324a) Polytropic compression
4325b) Isochoric heat addition
4326c) Isobaric heat addition
4327d) Isochoric and isobaric heat addition
432811. Which one of the following is part of air standard Stirling cycle?
4329a) Reversible isothermal compression
4330b) Polytropic expansion
4331c) Isobaric heat addition
4332d) Reversible isetropic compression
433312. Which one of the following is part of air standard Ericsson cycle?
4334a) Reversible isothermal compression
4335b) Polytropic expansion
4336c) Isochoric heat addition
4337d) Reversible isetropic compression
433813. Gas power cycle is not used for
4339a) Diesel cycle engine
4340b) Otto cycle engine
4341c) Locomotive engine
4342d) Aircraft engine
4343208
434414. Which one of the following has the maximum thermal efficiency for a given range of temperatures?
4345a) Carnot cycle
4346b) Rankine cycle
4347c) Joule cycle
4348d) Binary cycle
434915. Why is Rankine cycle considered as most practical cycle?
4350a) Saturation steam enters the turbine
4351b) Pump handle water vapour mixture
4352c) Complete condensation of steam in the condenser
4353d) Complete condensation of steam in the low pressure turbine
435416. The back work ratio is defined as
4355a) Net work done in the cycle/Heat supplied
4356b) Pump work/Turbine work
4357c) Net work output/Turbine work
4358d) Turbine work/pump work
435917. In the Rankine cycle, heat is added
4360a) isohermally
4361b) at constant volume
4362c) at constant pressure
4363d) adiabatically
436418. Specific steam consumption of Rankine cycle can be reduced steam
4365a) superheating
4366209
4367b) reheating
4368c) regeneration
4369d) condensation
437019. Rankine cycle efficiency of well maintained steam power plant is in the range of
4371a) less than 10%
4372b) 10% to 20%
4373c) 35% to 45%
4374d) 50% to 60%
437520. Rankine cycle with multiple regeneration can be approximated as
4376a) ideal Brayton cycle
4377b) Carnot vapour cycle
4378c) ideal Stirling cycle
4379d) Otto cycle
438021. In regenerative Rankine cycle, the feed water is heated by
4381a) exhaust steam
4382b) condensed steam
4383c) bled-off steam
4384d) fresh steam
438522. Specific steam consumption of a power plant is expressed as
4386a) pump work / turbine work
4387b) 3600 kJ / Wnet (kJ/kg)
4388c) 3600 (kJ) / Æžth(kWh)
4389d) turbine work / pump work
4390210
439123. A house hold refrigerator with a COP of 1.8 removes heat from a refrigerated space at a rate of 90 kJ/min. Then the electrical power consumed is
4392a) 0.633 kW
4393b) 0.733 kW
4394c) 0.833 kW
4395d) 0.933 kW
439624. A house hold refrigerator with a COP of 1.8 removes heat from a refrigerated space at a rate of 90 kJ/min. Then the heat rejected to the surroundings are
4397a) 130 kJ/min
4398b) 140 kJ/min
4399c) 150 kJ/min
4400d) 160 kJ/min
440125. In an internal combustion engine, during the compression stroke the heat rejected to the cooling water is 50 kJ/kg and the work input is 100 kJ/kg. The change in internal energy of the working fluid is
4402a) 0
4403b) 50 kJ/kg, gain
4404c) 50 kJ/kg, loss
4405d) 100 kJ/kg, loss
440626. A reversible heat engine rejects 50% of the heat supplied during a cycle of operation. If this engine is reversed and operates as a heat pump, then what is its coefficient of performance?
4407a) 1.0
4408b) 1.5
4409c) 2.0
4410211
4411d) 2.5
441227. A ballon which is initially collapsed and flat is slowly filled with a gas at 100 kPa, so as to form it into a sphere of 1m radius. The work done by the gas in tha ballon during the filling process is
4413a) 428.9 kJ
4414b) 418.9 kJ
4415c) 420.9 kJ
4416d) 416.9 kJ
441728. 2 kg of water at 80°C are mixed with adiabatically with 3 kg of water at 30°C in a constant pressure process of 1 atm. The increase in the entropy of the total mass of water due to mixing process is
4418a) -0.05915 kJ/K
4419b) 0.05915 kJ/K
4420c) 0
4421d) 5.915 kJ/K
442229. 0.1 cubic metres of hydrogen initially at 1.2 MPa, 200°C undergoes a reversible isothermal expansion to 0.1 MPa. The change in entropy of the gas is (gamma = 1.4)
4423a) -0.4889 kJ/kgK
4424b) 0.4886 kJ/kgK
4425c) -0.6294 kJ/kgK
4426d) 0.6294 kJ/kgK
442730. 80 kg of water at 100°C are mixed with 50 kg of water at 60°C while the temperature of the surroundings is 15°C. Determine the decrese in available enrgy due to mixing
4428a) 234.8 kJ
4429b) 130.04 kJ
4430212
4431c) 307.25 kJ
4432d) 406.09 kJ
443331. Which one of the following phenomena occurs when gas in a piston-in-cylinder assembly expands reversibiliy at constant pressure?
4434a) Heat is added to the gas
4435b) Heat is removed from the gas
4436c) Gas does work from its own stored energy
4437d) Gas undergoes adiabatic expansion
443832. In which one of the following processes, in a closed system the thermal energy transferred to a gas is completely converted to internal energy resulting in an increase in gas temperature
4439a) Isochoric process
4440b) Adiabatic process
4441c) Isothermal process
4442d) free expansion
444333. Determine the entropy of 1 kg of wet steam at a pressure of 6 bar and 0.8 dry, reckoned from freezing point (0°C). Given at p = 6 bar, Ts = 158.8°C, hfg = 2085 kJ/kg
4444a) 5.7 kJ/kgK
4445b) 3.4 kJ/kgK
4446c) 2.9 kJ/kgK
4447d) 7.2 kJ/kgK
444834. A Carnot engine rejects 30% of absorbed heat to a sink at 30°C. The temperature of the heat source is
4449a) 100°C
4450b) 433°C
4451213
4452c) 737°C
4453d) 1010°C
445435. An engine operates between temperature limits of 900 K, T2 and another between T2 and 400 K. For both to be equally efficient, the value of T2 will be
4455a) 700 K
4456b) 600 K
4457c) 750 K
4458d) 650 K
445936. A Carnot engine operates between 27°C and 327°C. If the engine produces 300 kJ of work, what is the entropy change during heat addition?
4460a) 0.5 kJ/K
4461b) 1.0 kJ/K
4462c) 1.5 kJ/K
4463d) 2.0 kJ/K
446437. The entropy of a mixture of ideal gases is the sum of the entropies of constituents evaluted at
4465a) temperature and pressure of the mixture
4466b) temperature of the mixture and the partial pressure of the constituents
4467c) temperature and volume of the mixture
4468d) pressure and volume of the mixture
446938. An inventor states that his new engine rejects to the sink 40% of heat absorbed from the source while the source and sink temperatures are 327°C and 27°C respectively. Therfore, his engine is equivalent to
4470a) Joule engine
4471b) Stirling engine
4472214
4473c) impossible engine
4474d) Carnot engine
447539. An ideal gas at 27°C is heated at constant pressure till its volume becomes three times. Then, what would be the temperature of gas?
4476a) 81°C
4477b) 627°C
4478c) 543°C
4479d) 327°C
448040. 0.7 kg/s of air enters with a spefic enthalpy of 290 kJ and leaves it with 450 kJ of specific enthalpy. Velocities at inlet and exit are 6 m/s and 2 m/s respectively. Assuming adiabatic process, what is power input to the compressor?
4481a) 120 kW
4482b) 118 kW
4483c) 115 kW
4484d) 112 kW
4485FLUID MECHANICS
44861. For steady incompressible flow through a closed-conduit of uniform cross-section, the direction of flow will always be,
4487a) from higher to lower elevation
4488b) from higher to lower pressure
4489c) from higher to lower velocity
4490d) from higher to lower piezometric head
44912. A circular pipe has a diameter of 1m, bed slope of 1in 1000, and Manning’s roughness coefficient equal to 0.01. It may be treated as an open channel flow when it is flowing just
4492215
4493full, i.e., the water level just touches the crest. The discharge in this condition is dented by Q(full). Similarly, the discharge when the pipe is flowing half-full, i.e. with a flow depth of 0.5m, is denoted by Q(half). The ratio of Q(full)/ Q(half)
4494a) 1
4495b) 1.414
4496c) 2
4497d) 4
44983. A triangular gate with a base width of 2m and a height of 1.5 m lies in a vertical plane. The top vertex of the gate is 1.5m below the surface of a tank which contains oil of specific gravity 0.8. Considering the density of water and acceleration due to gravity to be 1000 kg/cu.m and 9.81 m/s2 respectively, the hydrostatic force (in KN) exerted by the oil on the gate is
4499a) 2.5
4500b) 1.4
4501c) 3.4
4502d) 4.5
45034. A pipe of 0.7m diameter has a length of 6 km and connects two reservoirs A and B. The water level in reservoir A is at an elevation 30m above the water level in reservoir B. Halfway along the pipe line. There is a branch through which water can be supplied to a third reservoir C. The friction factor of the pipe is 0.024. The quantity of water discharged into reservoir C is 0.15 cumecs. Considering the acceleration due to gravity as 9.81 m/s2 and neglecting minor losses, the discharge (in cumes) in to the reservoir B is,
4504a) 1.56
4505b) 0.9
4506c) 2.25
4507d) 0.56
45085. An isohyet is a line joining points of
4509a) equal temperature
4510216
4511b) equal humidity
4512c) equal rainfall depth
4513d) equal evaporation
4514FLUID MECHANICS
45151. A perfect fluid (also known as an ideal fluid is)
4516a) a real fluid
4517b) the one which obeys perfect gas laws
4518c) compressive and gasseous
4519d) incompressible and frictionless
45202. When a shear stress is applied to a substance it is found to resist it by elastic deformation. The substance is
4521a) liquid
4522b) solid
4523c) gas
4524d) fluid
45253. The viscosity of
4526a) liquids increases with temperature
4527b) gases increases with temperature
4528c) fluids decreases with temperature
4529d) fluids increases with temperature
45304. A real fluids is any fluid which
4531a) has surface tension and is incompressible
4532217
4533b) has zero shear stress
4534c) has constant viscosity and density
4535d) has density
45365. Typical example of a non-Newtonian fluid of pseudoplastic variety is
4537a) Water
4538b) Air
4539c) Blood
4540d) Printing ink
45416. In a sample of water an increase of pressure by 18 MN/m2 caused 1% reduction in the volume. The bulk modulus of elasticity of this sample, in MN/m2 is
4542a) 1.8
4543b) 180
4544c) 1800
4545d) 0.18
45467. Broadly speaking, water is
4547a) 10 times more compressible than steel
4548b) 80 times more compressible than steel
4549c) 80 times less compressible than steel
4550d) 800 times les compressible than steel
45518. If a capillary rise of water is a 2mm diameter tube is 1.5cm, the height of capillary rise in a 0.5mm diameter tube, in cm, will be
4552a) 10.0
4553b) 1.5
4554c) 6.0
4555218
4556d) 24.0
45579. If the surface tension of water-air interface is 0.073 N/m, the guage pressure inside a rain drop of 1mm diameter is,
4558a) 146.0 N/m2
4559b) 0.146 N/m2
4560c) 73.0 N/m2
4561d) 292.0 N/m2
456210. The excess pressure (above atmospheric ) inside a soap bubble of diameter 1cm, by assuming the surface tension of soap solution to be 0.04 N/m, is
4563a) 32.0 N/m2
4564b) 16.0 N/m2
4565c) 160.0 N/m2
4566d) 0.32 N/m2
456711. The capillary rise in a 3 mm tube immersed in a liquid is 15 mm. If another tube of diameter 4mm is immersed in the same liquid the capillary rise would be
4568a) 11.25mm
4569b) 20.00mm
4570c) 8.4 mm
4571d) 26.67 mm
457212. An apparatus produces of water in air is 0.07N/m, the diameter of a tube that can be used to keep the capillary height between 1.80 cm to 2.00 cm is,
4573a) 1.65 mm
4574b) 3.33 cm
4575c) 1.65 cm
4576219
4577d) 1.40 cm
457813. At a liquid-air-The liquid is,
4579a) Wetting
4580b) Non-wetting
4581c) Ideal
4582d) Does not form a stable bubble
458314. At 20 deg. Centigragde, pure water will have a vapour pressure, in kPa, of about
4584a) 0.5
4585b) 2.34
4586c) 101.3
4587d) 8.67
458815. At 100 deg. Centigrade, at sea level, pure water will have a vapour pressure, in kPa, of about
4589a) 0.50
4590b) 2.3
4591c) 10.1
4592d) 101.3
459316. For a fluid at rest
4594a) the shear stress depends upon the coefficient of velocity
4595b) the shear stress is maximum on a plane inclined at 45 deg. To horizontal
4596c) the shear stress is zero
4597d) the shear stress is zero only on horizontal plane
4598220
459917. Normal stresses are of the same magnitude in all directions at a point in a fluid
4600a) only when the fluid is frictionless
4601b) only when the fluid is at rest
4602c) only when there is no shear stress
4603d) in all cases of fluid motion
460418. Local atmospheric pressure is measured by
4605a) Hydrometer
4606b) Barometer
4607c) Hygrometer
4608d) Altimeter
460919. Identify the correct statement
4610a) Local atmospheric pressure is always less than the standard atmospheric pressure
4611b) Local atmospheric pressure depends only on the elevation of the place
4612c) A barometer reads the difference between the local and standard atmospheric pressure
4613d) Standard atmospheric pressure is 760 mm of mercury
461420. Bourdon gauge measures
4615a) absolute pressure
4616b) gauge pressure
4617c) local atmospheric pressure
4618d) standard atmospheric pressure
461921. When the barometer reads 740.00mm of mercury, a pressure of 10kPa suction at that location is equivalent to
4620a) 10.02 m of water (abs)
4621221
4622b) 9.87 m of water (abs)
4623c) 88.53 kPa (abs)
4624d) 0.043 kPa (abs)
462522. The standard atmospheric pressure is 760 mm of mercury. At a certain location the barometer reads 710 mm of mercury. At this place an absolute pressure of 360mm of mercury corresponds to a gauge pressure, in mm of mercury
4626a) 400 mm of vaccum
4627b) 350 mm of vaccum
4628c) 760 mm of vaccum
4629d) 710 mm
463023. A barometer at a given location
4631a) shows the local atmospheric pressure which is variant with time
4632b) always shows the local atmospheric pressure which may change with time
4633c) shows the standard atmospheric pressure, if it is of aneroid type
4634d) shows the local temperature if it of mercury column type
463524. A U-tube manometer measures
4636a) absolute pressure at a point
4637b) local atmospheric pressure
4638c) difference in total energy between two points
4639d) difference in pressure between two points
464025. A U-tube open at both ends and made of 8mm diameter glass tube has mercury in the bottom to a height of 10 cm above the horizontal limb. If 19 cc of water is added to one the limbs, the difference in mercury levels at equilibrium is
4641a) 3.0 cm
4642222
4643b) 2.8 cm
4644c) 1.0 cm
4645d) zero
464626. A cylindrical tank of 2m diameter is laid with its axis horizontal and is filled with water just to its top. The force on one of its end plates is kN, is
4647a) 123.0
4648b) 61.51
4649c) 30.76
4650d) 19.58
465127. The centre of buoyancy of a submerged body
4652a) coincides with the centre of gravity of the body
4653b) coincides with the centroid of the displaced volume of the fluid
4654c) is always below the centre of gravity of the body
4655d) is always above the centroid of the displaced volume of liquid
465628. An object weighing 100N in air was found to weigh 75 N when fully submerged in water. The relative density of the object is
4657a) 4.0
4658b) 4.5
4659c) 2.5
4660d) 1.25
466129. An iceberg has 12% of its volume projecting above the surface of the sea. If the density of sea water is 1025 kg/cu.m, the density of the iceberg is
4662a) 875 kg/cu.m
4663b) 1000 kg/cu.m
4664223
4665c) 1148 kg/cu.m
4666d) 902 kg/cu.m
466730. A metal block is thrown into a deep lake. As it sinks deeper in water, the buoyant force acting on it
4668a) increases
4669b) remains the same
4670c) decreases
4671d) first increases and then decreases
467231. When a block of ice floating on water in a container melts, the level of water in the container
4673a) rises
4674b) first falls and then rises
4675c) remains the same
4676d) falls
467732. When a ship enters sea from a river one can expect it
4678a) to rise a little
4679b) to sink a little
4680c) to remain at the same level of draft
4681d) to rise or fall depending on whether it is of wood or steel
468233. Buoyant force is the
4683a) lateral force acting on a submerged body
4684b) resultant force acting on a submerged body
4685c) resultant hydrostatic force on a body due to fluid surrounding it
4686d) the resultant force due to water on a body
4687224
468834. If B=centre of buoyancy, G=is the centre of gravity and M=metacentre of a floating body, the body will be in stable equilibrium if
4689a) MG=0
4690b) M is below G
4691c) BG=0
4692d) M is above G
469335. A liquid undergoing a rigid body rotation in a container is said to have
4694a) circulatory flow
4695b) circulation
4696c) forced vertex motion
4697d) free vortex motion
469836. The Flow of a liquid at a constant rate in a conically tapered pipe is classified as
4699a) steady, uniform flow
4700b) steady, non-uniform flow
4701c) unsteady, uniform flow
4702d) unsteady, non-uniform flow
470337. A pathline is the
4704a) mean direction of a number of particles at the same instant of time
4705b) instantaneous picture of positions of all particles in the flow which passed a given point
4706c) trace made by a single particle over a period of time
4707d) path traced by continuously injected tracer at a point
470838. A streamline is a line
4709225
4710a) which is normal to the velocity vector at every point
4711b) which represents lines of constant velocity potential
4712c) which is normal to the lines of constant stream function
4713d) which is tangential to the velocity vector everywhere at a given instant
471439. In a steady flow
4715a) streamlines and pathlines are identical but are different from streakline
4716b) streakline and pathlines are identical but are different from streamlines
4717c) streamline, streakline and pathline can all be different from each other
4718d) none of the above
471940. In a rectangular channel 3m wide the depth of flow is 1.3m and the velocity is 1.6m/s. At a hydraulic structure 1.24 m3/s of discharge is withdrawn and the canal width is reduced to 2.5m. The depth of flow in this section at a velocity of 1.5 m/s is
4720a) 1.21m
4721b) 1.00m
4722c) 1.33m
4723d) 1.66m
472441. A flow has diverging straight streamlines. If the flow is steady, the flow
4725a) is a uniform flow with local acceleration
4726b) has convective normal acceleration
4727c) has convective tangential acceleration
4728d) has convective normal as well as tangential accelerations
472942. A flow has parallel curved streamlines and is steady. This flow has
4730a) tangential convective acceleration
4731b) local acceleration
4732226
4733c) normal convective as well as local acceleration
4734d) normal convective acceleration
473543. A velocity potential exists
4736a) whenever the real fluids flow exists
4737b) when the flow is real and rotational
4738c) when the flow satisfies the conditions of irrotational motion
4739d) when the flow satisfies the equations of continuity
474044. If a stream function exists it implies that
4741a) the stream function represent a possible flow field
4742b) the flow is irrotational
4743c) the flow is steady, incompressible
4744d) the potential function also exists
474545. Indicate the incorrect statement:
4746A flow net
4747a) is applicable to irrotational fluid flow
4748b) for a given boundary is the same whether the flow is in one direction or the other
4749c) for a given boundary is applicable to one chosen direction of flow; if the flow is reversed the flow net will change
4750d) will be so constructed that the size of the mesh is inversely proportional to the local velocity
475146. Bernoulli equation is applicable between any two points
4752a) in any rotational flow of an incompressible fluid
4753227
4754b) in any type of irrotational flow of a fluid
4755c) in steady rotational flow of an incompressible fluid
4756d) in steady, irrotational flow of an incompressible fluid
475747. The piezometric head of a flow is
4758a) the sum of the velocity head and datum head
4759b) the sum of the pressure head and velocity head
4760c) the sum of the pressure head and velocity head
4761d) the sum of the velocity head, pressure head and datum head
476248. In a flow of a real fluid with no addition of energy
4763a) the energy line will be horizontal or sloping upward in the direction of the flow
4764b) the energy line can never be horizontal or sloping upward in the direction of the flow
4765c) the piezometric line can never be horizontal or sloping downward in the direction of the flow
4766d) the centre line of the pipe can never be above the energy line
476749. The total head in a flow is the sum of
4768a) potential head and datum head
4769b) piezometric head and pressure head
4770c) piezometric head and velocity head
4771d) piezometric head, velocity head and datum head
477250. The difference between the total head line and the hydraulic grade line represents
4773a) the velocity head
4774b) the piezometric head
4775c) the pressure head
4776228
4777d) the elevation head
477851. In a pipeline the hydraulic grade line is above the pipe centre line is the longitudinal section at point A and below the pipe centre line at another point B. From this it can be inferred that
4779a) vaccum pressure prevail at B
4780b) vaccum pressure prevail at A
4781c) the flow is from A to B
4782d) the flow is from B to A
478352. In a two-dimensional duct flow air flows in the bottom half of the duct with uniform velocity and there is no flow in the upper half. The value of the kinetic energy correction factor for this flow is
4784a) 2.0
4785b) 2.25
4786c) 4.0
4787d) 3.0
478853. A 15 cm diameter pipe carries a flow of 70 lit/s of an oil (RD=0.75). At a section 12 cm above the datum the pressure is vaccum of 2 cm of mercury. If the kinetic energy correction factor for this section is 1.1,the total head at the section in meters of oil is
4789a) 0.648
4790b) 0.728
4791c) 0.557
4792d) 0.637
479354. A nozzle direct a liquid jet at an angle of elevation 45 deg. The hydraulic grade line for the jet
4794a) coincides with the centre line of the jet
4795b) will be horizontal at the level of the jet
4796229
4797c) will be horizontal at the level of the energy line
4798d) coincides with the energy line
479955. A pump delivers 50 L/s of water and delivers 7.5 kW of power to the system. The head developed by the pump is
4800a) 7.5m
4801b) 5.0m
4802c) 1.53m
4803d) 15.32m
480456. The linear momentum equation is based on
4805a) Newton’s law of viscosity
4806b) Newton’s first law
4807c) Newton’s second law
4808d) Newton’s third law
480957. A control volume is
4810a) the volume of fluid flowing per unit of time
4811b) a volume fixed in space
4812c) the volume in which a control device is situated
4813d) the volume of the fluid controlling device
481458. The line momentum equation is
4815a) scalar relation
4816b) an approximate relation for engineering analysis
4817c) a relation applicable to incompressible fluids only
4818d) a vector relation
4819230
482059. The linear momentum equation applied to a control volume in a flow through a nozzle yielded the resultant reaction force R, on the fluid in the control volume. The force required to keep the nozzle in position is
4821a) the same as R in magnitude and direction
4822b) equal to R but opposite in direction
4823c) equal to the x-component of R
4824d) equal to R minus the friction force
482560. A jet of oil (R=0.8) has an area of 0.02 sq.m and a velocity of 10 m/s. If it strikes a plate normally, the force exerted on the plate is
4826a) 1597 N
4827b) 1996 N
4828c) 15665 N
4829d) 19581 N
483061. A water jet has an area of 0.03 sq.m and impinges normally on a plate. If a force of 1 kN is produced as a result of this impact, the velocity of the jet, in m/s, is
4831a) 15
4832b) 33.4
4833c) 3.4
4834d) 5.78
483562. A water jet 0.015 sq.m in area has a velocity of 15 m/s. If this jet impinges normally on a plate which is moving at a velocity of 5 m/s in the direction of the jet, the force on the plate due to this impact is
4836a) 3368 N
4837b) 2246 N
4838c) 14907 N
4839231
4840d) 14686 N
484163. A fire hose has a nozzle attached to it and the nozzle discharges a jet of water into the atmosphere at 20 m/s. This places the joint of the nozzle
4842a) in compression
4843b) in tension
4844c) in a state of zero stress
4845d) in bending stresses
484664. A two-dimensional jet strikes a fixed two-dimensional plane at 45 deg. To the normal to the plane. This causes the jet to split into two streams whose discharges are in the ratio
4847a) 1.0
4848b) 2.41
4849c) 5.83
4850d) 1.414
485165. The velocity distribution over one half of a cross section is uniform and is zero over the remaining half. The momentum correction factor for this cross section is
4852a) 2.0
4853b) 4.0
4854c) 1.0
4855d) 3.0
485666. Hydraulic grade line for flow in a pipe of constant diameter is
4857a) always above the centreline of the pipe
4858b) always above the energy grade line
4859c) always sloping downwards in the direction of the flow
4860d) coincides with the pipe centreline
4861232
486267. The minor loss due to sudden contraction is due to
4863a) flow contraction
4864b) expansion of flow after sudden contraction
4865c) boundary friction
4866d) cavitation
486768. Minor losses in a pipe flow are those losses
4868a) which are insignificantly small
4869b) which can be neglected always
4870c) caused by local disturbance due to pipe fittings
4871d) caused by frictional resistance
487269. Two identical pipes of length L, diameter D and friction factor f, are connected in series between two reservoirs. The size of a pipe of length L and of the same friction factor f, equivalent to the above pipes, is
4873a) 0.5D
4874b) 0.87D
4875c) 1.15D
4876d) 1.40D
487770. Two identical pipes of length L, diameter D and friction factor f, are connected in parallel between two reservoirs. The size of a pipe of length L and of the same friction factor f, equivalent to the above pipes, is
4878a) 0.5D
4879b) 0.87D
4880c) 1.40D
4881d) 2.0D
4882233
488371. In using Darcy-Weisbach equation for flow in a pipe, the friction factor is misjudged by +25%. The resulting error in the estimated discharge Q is
4884a) +25%
4885b) -16.67%
4886c) -5%
4887d) -12.5%
488872. A pipeline connecting two reservoirs has its diameter reduced by 10% over a length of time due to chemical deposit action. If the friction factor remains unaltered, for a given head difference in the reservoirs this would reflect in a reduction in discharge of
4889a) 10%
4890b) 14.6%
4891c) 23.2%
4892d) 31.6%
489373. Three pipes are connected in series. Then
4894a) the head loss in each pipe is the same
4895b) the total discharge is the sum of the discharges in the individual pipes
4896c) the discharge through each pipe is the same
4897d) the Reynolds number for each pipe is the same
489874. The discharge Q in a pipe of know f is estimated by using the head loss hf in a length L and diameter D. If an error of 1% is involved in the measurement of D, the corresponding error in the estimation of Q is
4899a) 2.5%
4900b) 1.0%
4901c) 0.4%
4902d) 5%
4903234
490475. In a pipe network
4905a) the algebraic sum of discharges around each elementary circuit must be zero
4906b) the head at each node must be the same
4907c) the algebraic sum of the piezometric head drops around each elementary circuit is zero
4908d) the piezometric head loss in each line of a circuit is the same
490976. The equations of motion for laminar flow of a real fluid are known as
4910a) Euler’s equation
4911b) Bernoulli equation
4912c) Navier-Stokes equation
4913d) Hagen-Poiseuille equation
491477. Identity the incorrect statement
4915a) Laminar flow is rotational
4916b) Loss of head in laminar flow in a pipe is proportional to square of the velocity
4917c) In laminar flow the friction factor f is directly proportional to the Reynolds number
4918d) In laminar flow in a conduit the shear stress varies linearly across the pipe
491978. In a two-dimensional, steady, horizontal, uniform laminar flow the shear gradient in the normal direction is equal to
4920a) the velocity gradient in the normal direction
4921b) the velocity gradient in the longitudinal direction
4922c) the pressure gradient in the normal direction
4923d) the pressure gradient in the direction of flow
492479. An oil of kinematic viscosity 0.25 stokes flows through a pipe of diameter 10cm. The flow is critical at a velocity of
4925235
4926a) 7.2 m/s
4927b) 5.0 m/s
4928c) 0.5 m/s
4929d) 0.72 m/s
493080. In a steady flow of an oil in a pipe in laminar regime the shear stress is
4931a) constant across the pipe
4932b) maximum at the centre and decreases parabolically towards the sides
4933c) zero at the boundary and increases linearly towards the centre
4934d) zero at the centre and increases linearly towards the boundary
493581. Oil of viscosity 1.5 Pa.s and relative density 0.9 flows through a circular pipe of diameter 5cm with a mean velocity of 1.2 m/s. The shear stress at the wall in Pa is
4936a) 360
4937b) 288
4938c) 180
4939d) 144
494082. In a circular pipe of certain length carrying oil at a Reynolds number 100, it is proposed to triple the discharge. If the viscosity remains unchanged, the power input will have to be
4941a) decreased to 1/3 its original value
4942b) increased by 100%
4943c) increased to 3 times the original value
4944d) increased to 9 times its original value
494583. The minimum value of friction factor f that can occur in laminar flow through a circular pipe is
4946a) 0.025
4947236
4948b) zero
4949c) . 0.064
4950d) 0.032
495184. A 20cm diameter pipe carries a fluid of relative density 0.9. If the boundary shear stress in the pipe is 0.50 Pa, the head loss in a length of 100m of the pipe line is
4952a) 11.35m
4953b) 4.54m
4954c) 0.36m
4955d) 9.08m
495685. The friction factor f in a laminar pipe flow was found to be 0.04.The Reynolds number of the flow was
4957a) 2000
4958b) 1000
4959c) 800
4960d) 1600
496186. Uniform flow in a channel is characterised by the following statement:
4962a) Total energy remains constant along the channel
4963b) Gradient of the total energy is parallel to the channel bed
4964c) Specific energy decreases along the channel
4965d) The total energy line either rises or falls depending upon the Froude number
496687. Uniform flow in an open channel exists when the flow is steady and the
4967a) channel is frictionless
4968b) channel is non-prismatic
4969c) channel is prismatic
4970237
4971d) channel is prismatic and the depth of flow is constant along the channel
497288. In defining a Froude number applicable to channels of any shape, the length parameter used is the
4973a) depth of flow
4974b) hydraulic radius
4975c) ratio of area to top width
4976d) wetted perimeter
497789. The flow can be uniform in
4978a) a non-prismatic channel
4979b) a wide rectangular channel
4980c) a horizontal trapezoidal channel
4981d) a frictionless rectangular channel
498290. The term alternate depths in open channel flow is used to designate the depths
4983a) at the beginning and end of hydraulic jump
4984b) having the same kinetic energy for a given discharge
4985c) having the same specific energy for a given discharge
4986d) at the beginning and end of a gradually varied flow profile
498791. Which of the following is not a dimensionless number:
4988a) Darcy-Weisbach friction factor f
4989b) Coefficient of drag Cd
4990c) Manning’s coefficient n
4991d) coefficient of velocity Cv
4992238
499392. Which of the following is a dimensionless number:
4994a) Manning’s coefficient n
4995b) Pipe friction factor f
4996c) Chezy coefficient C
4997d) Hazen-William coefficient CH
499893. Dynamic similarity is said to exist between two fluids flows when at corresponding points there are
4999a) geometrical similarity and similarity of forces involved
5000b) kinematic similarity and dynamic similarity
5001c) interaction of inertia and viscous forces
5002d) interaction between inertia, viscous and pressure forces
500394. In hydraulic modelling of flow pattern around a body submerged in a fluid the non-dimensional number which has to be kept the same in the model and prototype is
5004a) Weber number
5005b) Froude number
5006c) Reynolds number
5007d) Strouhal number
500895. The fall velocity of a sand grain in water is to be modelled by using particles of the same relative density as sand and a liquid whose kinematic viscosity is 100 times larger than that of water. The diameters of the particles in the model that will have the same fall velocity as the prototype will be
5009a) 10 times smaller
5010b) 10 times larger
5011c) 100 times smaller
5012d) 100 times larger
5013239
501496. The drag force on a body
5015a) is the net frictional force on the body
5016b) is the net pressure force on the body
5017c) is the component of the resultant force in the direction of the relative velocity
5018d) is the component of the resultant force in a direction perpendicular to the direction of gravity
501997. The lift force on a body
5020a) is due to buoyant force
5021b) is always in the direction of the gravity
5022c) is the component of the resultant force in a vertical directions
5023d) is the component of the resultant force in a direction normal to relative velocity
502498. In calculating the drag force using CD the area used is
5025a) always the frontal area
5026b) the planform area when the body is flat like an airfoil
5027c) the planform area when the body is bluff like a sphere
5028d) always the planform area
502999. Pressure drag results due to
5030a) formation of wake
5031b) turbulence in the wake
5032c) existence of stagnation point in the front of a body
5033d) high Reynolds number
5034100. A streamlined body with a round nose and a tapering back is generally best suited for
5035a) creeping motion
5036240
5037b) turbulent sub-sonic flow
5038c) supersonic flow
5039d) laminar flow with low Reynolds number
5040241
5041FLUID MECHANICS
50421. The bulk modulus of elasticity for a liquid, K
5043a) is a function of both temperature and pressure
5044b) at any given temperature decreases continuously with pressure
5045c) at any pressure increases continuously with temperature
5046d) is a constant
50472. The predominant fluid property associated with cavitation phenomenon is,
5048a) Surface tension
5049b) Vapour pressure
5050c) Mass density
5051d) Bulk modulus of elasticity
50523. A rectangular plate 0.75mx2.4m is immersed in a liquid of relative density 0.85 with its 0.75m side horizontal and just at the water surface. If the plane of the plate makes an angle of 60 deg. With the horizontal, the pressure force on one side of the plate in kN is,
5053a) 15.6
5054b) 7.8
5055c) 24.0
5056d) 18.0
50574. An object weights 50N in water and 80N in an oil of relative density 0.80. Its volume in litres is
5058a) 15.3
5059b) 60.0
5060c) 30.6
5061d) 50.0
5062242
50635. Lines of constant stream function
5064a) are parallel streamlines
5065b) are parallel to the streamlines
5066c) are normal to the streamlines
5067d) can intersect each other
50686. The potential function exist for
5069a) irrotional motion of incompressible fluids only
5070b) irrotational motion of fluids whether compressible or incompressible
5071c) for two-dimensional irrotational flow only
5072d) for steady flows only
50737. In a siphon the summit is 4m above the water level in the reservoir from which the flow is being discharged out. If the head loss from the inlet of the siphon to the summit is 2m and the velocity head at the summit is 0.5n the pressure at the summit is
5074a) -63.64 kPa
5075b) -9.0m of water
5076c) 6.5m of water (abs)
5077d) -39.16 kPa
50788. Two pipelines of equal length and diameter of 20 cm and 30 cm respectively are connected in parallel between two reservoirs. If the friction actor f is the same for both the pipes, the ration of the discharges in the smaller to the larger size of the pipe is
5079a) 0.363
5080b) 0.444
5081c) 0.667
5082d) 0.137
5083243
50849. In a pipeline design the usual practice is to assume that due to aging
5085a) the effective factor increases linearly with time
5086b) the friction factor increases linearly with time
5087c) the pipe become smoother with time
5088d) the friction factor decreases linearly with time
508910. The pressure drop in an 8 cm horizontal pipe is 75 kPa in a distance of 15m. The shear stress at the pipe wall, in kPa is
5090a) 0.2
5091b) 2.0
5092c) 5.0
5093d) 0.4
509411. The Reynolds number for the flow of oil in a certain pipe is 640. The Darcy-Weisbach friction factor f for the flow is
5095a) 0.02
5096b) 0.01
5097c) 0.1
5098d) 0.064
509912. The sequent depths in a hydraulic jump formed in a 4.0m wide rectangular channel are 0.2m and 1.0m. The discharge in the channel in cumecs is
5100a) 5.00
5101b) 1.12
5102c) 2.17
5103d) 4.34
5104244
510513. In a hydraulic jump occurring in a horizontal rectangular channel the sequent depths are 0.25m and 1.25m. The energy loss in this jump is
5106a) 0.8m
5107b) 1.0m
5108c) 1.25m
5109d) 1.50m
511014. In an automobile travelling at 60 km/h the power expended in overcoming wind resistance in 1.5 kN. If the automobile travels in 90 km/h the power expended in overcoming wind resistance in kW is
5111a) 2.25
5112b) 3.38
5113c) 5.06
5114d) 7.59
511515. In the flow past bluff bodies
5116a) the frictional drag is larger than the pressure drag
5117b) the pressure drag forms considerably large portion of the total drag
5118c) total drag is considerably smaller than that for a corresponding streamlined body
5119d) frictional drag forms considerably large portion of the drag
512016. In a fluid flow, point A is at a higher elevation than point B. The head loss between these points is HL. The total heads at A and B are Ha and Hb respectively. The flow will takes place
5121a) from A to B if Ha+HL=Hb
5122b) from B to A if Ha+HL=Hb
5123c) from B to A if Ha+HL=Hb
5124d) always from A to B
5125245
512617. In a siphon the summit is 4m above the water level in the reservoir from which the flow is being discharged out. If the head loss from the inlet of the siphon to the summit is 2m and the velocity head at the summit is 0.5m the pressure at the summit is
5127a) -63.64 kPa
5128b) -9.0m of water
5129c) 6.5m of water (abs)
5130d) -39.16 kPa
513118. In a turbulent pipe flow, inside the laminar boundary layer the velocity distribution is
5132a) parabolic
5133b) linear
5134c) logarithmic
5135d) exponential decay type
513619. In a turbulent flow through a pipe the centreline velocity is 3.61 m/s and the friction factor f=0.002. The mean velocity of the flow in m/s is
5137a) 4.80
5138b) 3.00
5139c) 2.21
5140d) 0.96
514120. The head loss in 100m length of a 0.1m diameter pipe (f=0.02) carrying water is 10m. The boundary shear stress, in kPa, is
5142a) 9.79
5143b) 0.298
5144c) 0.1958
5145d) 0.0245
5146246
5147Fundamentals of Manufacturing Processes
51481. A cube shaped casting solidifies in 5 minutes. The solidificaiton time of the cube of same material which is 8 times heavier than the original casting, will be,
5149a) 10 min
5150b) 20 min
5151c) 24 min
5152d) 40 min
51532. Two cubes of same material and size are cast using the sand casting process. The top face of one cube is completely insulated. The ratio of the solidification time of the cube with top face insulated to the other cube is,
5154a) 25/36
5155b) 36/25
5156c) 1
5157d) 6/5
51583. While cooling, a cubical casting of side 40mm undergoes 3%, 4% and 5% volume shrinkage during liquid state, phase transition state and solid state, respectively. The volume of metal compensation from the riser is
5159a) 2%
5160b) 7%
5161c) 8%
5162d) 9%
5163247
51644. Two streams of liquid metal which are not hot enough to fuse properly result in to a casting defect known as
5165a) cold shut
5166b) swell
5167c) sand wash
5168d) scab
51695. In a gating system, the ratio 1:2:4 represents
5170a) Sprue base area: runner area: ingate area
5171b) Pouring basin area: ingate area: runner area
5172c) Sprue base area:ingate area:casting area
5173d) Runner area: ingate area: casting area
51746. A solid cylinder of diameter 100mm and height 50mm is forged between two frictionless flat dies to a height of 25mm. The percentage change in diameter is
5175a) 0
5176b) 2.01
5177c) 20.7
5178d) 41.4
51797. The welding process which uses a blanket of fusible granular flux is
5180a) Tungsten inert gas welding
5181b) Submerged arc welding
5182c) Electroslag welding
5183d) Thermit welding
51848. In a full-mould (cavity-less) casting process, the pattern is made of
5185248
5186a) Expanded polystyrene
5187b) Wax
5188c) Epoxy
5189d) Plaster of paris
51909. A strip with a cross section of 150mm x 4.5 mm is being rolled with 20% reduction of area using 450mm diameter rolls. The angle subtended by the deformation zone at the roll center in radians, is,
5191a) 0.01
5192b) 0.02
5193c) 0.03
5194d) 0.06
519510. In deep drawing of sheets, the values of limiting draw ratio depends on
5196a) Percentage elongation of sheet metal
5197b) Yield strength of sheet metal
5198c) Type of press used
5199d) Thickness of sheet
5200Fundamentals of Manufacturing Processes
52011. When a metal is specified as “tough” in the part drawing, the manufacturing engineer should understand that this metal:
5202a) resists grinding
5203b) does not deform plastically but breaks into pieces when stressed
5204c) dulls tools almost immediately
5205d) resists being broken or deformed by mechanical shock forces
5206249
52072. This process recognizes the inherent interrelationships between design and manufacturing:
5208a) Design for manufacture
5209b) Design for manufacture and assembly
5210c) Design for concurrent engineering
5211d) Design for assembly
52123. This is a solid shape that fits inside the mold and forms a hole in a cooled cast metal or molten plastic object:
5213a) Core
5214b) Cavity
5215c) Prototype
5216d) Hole mold
52174. When a metal is specified as “hard”, then the manufacturing engineer should understand that :
5218a) the metal resists indentation
5219b) penetration and scratching
5220c) the same thing as toughness
5221d) the metal can deform plastically
52225. Which of the following is the best engineering plastics material that has high tensile strength, high compressive strength, with minimal elongation to use for a product that will be injection molded?
5223a) polycarbonate
5224b) polystyrene
5225c) phenolic
5226d) epoxy
5227250
52286. The best process for making a kitchen drawer divider tray out of plastic sheets is:
5229a) pultrusion
5230b) thermoforming
5231c) compression forming
5232d) blow molding
52337. A turning operation is to be done on a piece of alloy steel that has a diameter of 90mm. If the depth of cut is set at 3.175 mm, the feed is set at 0.30 mm per revolution, and the recommended cutting speed using a carbide tool is 90 meters per minute, what rotational speed you will set on the machine, from the following available speeds on machine, in rpm?
5234a) 118
5235b) 218
5236c) 318
5237d) 418
52388. The purpose of a riser in a mold is
5239a) to help raise the mold from the floor while preparing the mold
5240b) to do a function same as the cope while preparing the mold
5241c) to enhance the draft
5242d) to feed liquid metal into the body of casting as it solidifies
52439. Emulsified oils which are used in machine shop are
5244a) high in sulphur content
5245b) mixture of oil and water used for lubricating and cooling
5246c) lubricating oils diluted with naphta, kerosene or other petroleum-base solvents.
5247d) oils that have degraded over time
5248251
524910. Chills are used in moulds to
5250a) reduce the possibility of blow holes
5251b) achieve directional solidification
5252c) reduce freezing time
5253d) smoothen metal flow for reducing splatter
525411. In foundry work, a runner is which one of the following:
5255a) channel in the mold leading from the downsprue to the main mold cavity
5256b) foundryman who moves the hot molten metal from the furnace to the mold
5257c) vertical channel into which the metal is poured into the mold from a laddle
525812. Total solidification time is defined as which one of the following:
5259a) time between pouring and
5260complete solidification
5261b) time between pouring and cooling to room temperature
5262c) time between solidification and cooling to room temperature
5263d) time to give up the heat of fusion
526413. Chvorinov's rule states that total solidification time is proportional to which one of the following quantities? ( where A = surface area of casting, Hf = heat of fusion, Tm = melting temperature, and V = volume of casting, X^y means X raised to power y)
5265a) (A / V)^n
5266b) Hf
5267c) Tm
5268d) V
5269e) V/A
5270f) (V/A)^2
5271252
527214. In a sand-casting mold, the V/A ratio of the riser should be
5273a) equal to the V/A ratio of the casting itself
5274b) greater than the V/A ratio of the casting itself
5275c) smaller than the V/A ratio of the casting itself
527615. In sand casting, the volumetric size of the pattern is
5277a) bigger than the cast part
5278b) same size as the cast part
5279c) smaller than the cast part
528016. Given that Wm = weight of the molten metal displaced by a core and Wc = weight of the core, the buoyancy force is which one of the following?
5281a) downward force = Wm + Wc
5282b) downward force =Wm - Wc
5283c) upward force = Wm + Wc
5284d) upward force = Wm - Wc
528517. Which of the following materials require largest shrinkage allowance while making a pattern for a casting?
5286a) Plain Carbon steel
5287b) Aluminum
5288c) Brass
5289d) Cast Iron
529018. Disposable patterns are made of
5291a) wood
5292b) rubber
5293253
5294c) polystyrene
5295d) metal
529619. Shrinkage allowance on pattern is provided to compensate for shrinkage when
5297a) temperature of metal drops from pouring to room temperature
5298b) metal changes from liquid state to solid state at freezing temperature
5299c) temperature of solid phase drops from freezing temperature to room temperature
5300d) temperature of liquid metal drops from pouring to freezing temperature of the metal
530120. The purpose of chaplets in a mould is to
5302a) provide venting
5303b) induce directional solidification
5304c) compensate for shrinkage from pouring temperature to freezing temperature
5305d) to support the core
530621. In sand molding, core prints are used to
5307a) strengthen the core so that it will not crumble while pouring
5308b) form seat to support and hold the core in place
5309c) fabricate the core
531022. In sand molding draft is provided on the
5311a) casting
5312b) cavity
5313c) pattern
531423. Shell moulding requires
5315a) Wooden patterns
5316254
5317b) Sand patterns
5318c) Metal patterns
5319d) Polystyrene patterns
532024. In a casting process, fluidity is mostly influenced by
5321a) melting temperature
5322b) tapping temperature
5323c) pouring temperature
5324d) solidification temperature
532525. Sprue in sand casting refers to
5326a) gate
5327b) runner
5328c) riser
5329d) vertical passage
533026. In sand molding there is no need to provide one of the following allowance, it is
5331a) Shrinkage allowance
5332b) draft allowance
5333c) distortion allowance
5334d) machining allowance
533527. In sand molding, a slick refers to
5336a) a round sieve
5337b) a long, flat metal plate fitted with an offset handle
5338c) used to make or repair corners in the mould
5339d) used to scoop sand deep in the mould
5340255
534128. The purpose of sprue is to
5342a) feed the cavity at a rate consistent with the rate of solidification
5343b) act as a reservoir for molten metal
5344c) help feed the casting until the solidification takes place
5345d) feed molten metal from pouring basin to gate
534629. In sand mold, the purpose of gate is to
5347a) feed the cavity at a rate consistent with the rate of solidification
5348b) act a a reservoir for molten metal
5349c) help feed the casting until all solidification takes place
5350d) feed molten metal from pouring basin to the gate
535130. The purpose of riser is to
5352a) feed the cavity at a rate consistent with the rate of solidification
5353b) act as a reservoir for molten metal
5354c) help feed the casting until solidification takes place
5355d) feed molten metal from pouring basin to gate
535631. Preheating of parent metal plates before welding is done to
5357a) make the steel softer
5358b) burn away oil, grease, etc from the plate surface
5359c) prevent cold cracks
5360d) prevent plate distortions
536132. Metal better weldable with itself is
5362a) stainless steel
5363256
5364b) copper
5365c) bronze
5366d) mild steel
536733. Metal which can be suitable welded by TIG welding is
5368a) aluminum
5369b) stainless steel
5370c) pure titanium
5371d) aluminum, stainless steel and pure titanium
537234. Main advantage of MIG welding (GMAW) over TIG welding is that
5373a) the former can be used to weld hard metals
5374b) former permits use of large currents there by allowing higher deposition
5375c) welding rate is very fast
5376d) welding is completely automatic
537735. Thermit welding is
5378a) a process which uses a mixture of iron oxide and granular aluminum
5379b) accomplished by maintaining a hot molten metal pool between plates
5380c) a process in which arc is maintained under a blanket of flux
5381d) not a welding process
538236. Submerged arc welding is
5383a) a process which uses a mixture of iron oxide and granular aluminum
5384b) accomplished by maintaining a hot molten metal pool between the plates
5385c) a process in which arc is maintained under a blanket of flux
5386257
538737. In gas welding, maximum temperature occurs at
5388a) the tip of flame
5389b) the inner cone
5390c) next to the inner cone
5391d) at the outer cone
539238. Temperature of the plasma torch is of the order of
5393a) 1000 deg C
5394b) 5000 deg C
5395c) 10000 deg C
5396d) 30000 deg C
539739. In reverse polarity welding
5398a) electrode holder is connected to negative polarity and the work to the positive poloarity
5399b) electrode holder is connected to positive polarity and the work to the negative polarity
5400c) work is positive and the holder is earthed
5401d) holder is positive and the work is earthed
540240. Amperage setting in the electric arc welding (SMAW) depends on
5403a) work thickness
5404b) arc gap
5405c) electrode rod diameter
540641. Consumable electrode is used in the following welding process: -
5407a) TIG
5408b) MIG(GMAW)
5409c) Thermit
5410258
5411d) LBM
541242. Ratio of oxygen to acetylene for complete combustion is
5413a) 1:1
5414b) 1.5:1
5415c) 2:1
5416d) 2.5:1
541743. If two pieces of different metals are to be welded by projection welding, then the projection should be done on the metal piece having
5418a) higher conductivity
5419b) lower conductivity
5420c) same conductivity
542144. Multi spot welding is infact a
5422a) seam welding
5423b) projection welding
5424c) thermit welding
5425d) percussion welding
542645. Meterial difficult to be spot welded is
5427a) stainless steel
5428b) copper
5429c) mild steel
543046. In fusion welding, porosity defect is due to
5431a) high welding speed
5432259
5433b) low welding speed
5434c) wrong size of electrode
5435d) poor base metal
543647. Voltage during the arc-striking compared to the voltage during welding in electric arc welding is
5437a) same
5438b) more
5439c) less
5440d) unpredictable
544148. The weld pool is surrounded by an inert gas in
5442a) arc welding (SMAW)
5443b) carbon arc welding
5444c) MIG(GMAW)
5445d) submerged arc welding
544649. Filler metal is used in
5447a) electric spot welding
5448b) electric arc welding
5449c) projection welding
545050. Electroslag welding is
5451a) a process which uses a mixture of iron oxide and granular aluminum
5452b) accomplished by maintaining a hot molten metal pool between plates
5453c) a process in which arc is maintained under a blanket of flux
5454d) there is nothing called electro slag welding
5455260
545651. Arc length in an arc welding should be equal to
5457a) half the diameter of the electrode rod
5458b) diameter of the electrode rod
5459c) twice the diameter of the electrode rod
5460d) 2.5 times the electrode rod diameter
546152. Filler material is essentially used in
5462a) gas welding
5463b) spot welding
5464c) seam welding
546553. Grey iron is generally welded by
5466a) gas welding
5467b) arc welding
5468c) TIG welding
5469d) MIG welding
547054. Copper is
5471a) easily spot welded
5472b) very difficult to be spot welded
5473c) suitable for spot welding just as anyother metal
5474d) preferred to be welded by spot welding
547555. In electrical resistance welding
5476a) voltage is high and current is low
5477b) voltage if low and current is high
5478261
5479c) both voltage and current are high
5480d) both voltage and current are low
548156. An example of plastic welding is
5482a) arc welding
5483b) gas welding
5484c) forge welding
548557. In sintering stage of powder metallurgy, which of the following process take place?
5486a) all the pores reduce in size
5487b) the powder particles fuse and join together
5488c) Particles do not meet, but a bond is formed between them
5489d) some of the pores grow
549058. In production of precision components, the use of powder metallurgy technique mainly reduces
5491a) material cost
5492b) machining cost
5493c) equipment cost
5494d) tool-related costs
549559. Widely used metal powder production method for powder metallurgy is
5496a) crushing using impact
5497b) liquid metal spray
5498c) electrolytic deposition
549960. One of the process used to manufacture crankshafts is
5500262
5501a) cold heading
5502b) casting
5503c) pressure die casting
5504d) investment casting
550561. Most suitable process for manufacturing carburettor body is
5506a) cold heading
5507b) casting
5508c) pressure die casting
5509d) investment casting
551062. Most suitable process for manufacturing nails is
5511a) cold heading
5512b) casting
5513c) pressure die casting
5514d) investment casting
551563. Extrusion process can effectively reduce the cost of production through
5516a) in-process tooling costs
5517b) material saving
5518c) saving in adminstrative cost
551964. Major problem in hot extrusion is
5520a) design of punch
5521b) design of die
5522c) wear and tear of die
5523d) wear of punch
5524263
552565. An extrusion process is not the process where
5526a) complex sections are extruded from bar stocks
5527b) good surface finish and close tolerances are achievable
5528c) strength of finished product is improved if done in cold working
5529d) pulling foces are involved
553066. Upsetting or cold heading is a
5531a) rolling process
5532b) extrusion process
5533c) bending process
5534d) forging process
553567. Material good for extrusion is
5536a) stainless steel
5537b) brass casting
5538c) low carbon annealed steel
5539d) low carbon work hardened steel
554068. Seam less tube can be produced by
5541a) two high rolling mill
5542b) ring rolling combined with stretch forming
5543c) piercing
5544d) steam hammer forging
554569. A tooth paste tube can be produced by
5546a) solid forward extrusion
5547264
5548b) solid backward extrusion
5549c) hollow backward extrusion
5550d) hollow forward extrusion
555170. Rolling process can not be used to produce
5552a) a T section bar
5553b) a hollow circular section
5554c) a channel section bar
5555d) an I-section bar
555671. Bottom side of the sheet (tension side) do not have any contact with the die in
5557a) V-bending
5558b) air bending
5559c) wipe bending
556072. Stretch forming is a process in which
5561a) all deformations occur in the direction of stretch
5562b) all forces are applied in the direction of stretch
5563c) Plastic state induced due to stretch is exploited
5564d) no dies are used
556573. Advantage of cold forming is
5566a) grain refinement takes place
5567b) strength and hardness increase
5568c) no subsequent heat treatent is needed
5569d) force required is relatively small
5570265
557174. Close dimensional tolerances are maintained in cold formed parts because
5572a) dies are made of exact dimensions
5573b) no shrinkage occurs
5574c) strength increases
5575d) higher deforming force is applied
557675. Effect associated with the parts that are cold formed is
5577a) shrinkage
5578b) strain hardening
5579c) surface decoloring
5580d) surface roughness
558176. Which of the following machine part is not cold-formed?
5582a) Food container
5583b) stainless steel vessel
5584c) crankshaft
5585d) heating duct
558677. In sheet metal press operation, the size of the blanked part is dependent on the size of the
5587a) punch
5588b) die
5589c) average of punch and die
5590d) die plus clearance
559178. Which of the following processes start with a material that is in a fluid or semifluid state and solidifies the material in a cavity (two best answers):
5592a) casting
5593266
5594b) forging
5595c) machining
5596d) molding
5597e) pressing
559879. Which one of the following engineering materials is defined as a compound containing metallic and nonmetallic elements:
5599a) ceramic
5600b) composite
5601c) metal
5602d) polymer
560380. Deformation processes include which of the following (two correct answers):
5604a) casting
5605b) drilling
5606c) extrusion
5607d) forging
5608e) milling
560981. Which one of the following is a machine used to perform extrusion:
5610a) forge hammer
5611b) milling machine
5612c) rolling mill
5613d) press
5614e) torch
561582. Which of the following metals are used as the matrix material in fiber-reinforced MMCs (two best answers):
5616267
5617a) aluminum
5618b) copper
5619c) iron
5620d) magnesium
5621e) zinc
562283. Ceramic matrix composites are designed to overcome which of the following weaknesses of ceramics (two best answers):
5623a) compressive strength
5624b) hardness
5625c) hot hardness
5626d) modulus of elasticity
5627e) tensile strength
5628f) toughness
562984. Which one of the following polymer types are most commonly used in polymer matrix composites:
5630a) elastomers
5631b) thermoplastics
5632c) thermosets
563385. In glass working, a lehr is which of the following:
5634a) a lion's den
5635b) a melting furnace
5636c) a sintering furnace
5637d) an annealing furnace
5638268
563986. Which of the following are sections of a conventional extruder barrel for thermoplastics? (three best answers):
5640a) compression section
5641b) die section
5642c) feed section
5643d) heating section
5644e) metering section
5645f) shaping section
564687. Which two of the following are the principal components of an injection molding machine?
5647a) clamping unit
5648b) hopper
5649c) injection unit
5650d) mold
5651e) part ejection unit
565288. In rotational molding, centrifugal force is used to force the polymer melt against the surfaces of the mold cavity where solidification occurs:
5653a) true
5654b) false
565589. Hand lay-up is classified in which of the following general categories of PMC shaping processes (two best answers)?:
5656a) closed mold process
5657b) compression molding
5658c) contact molding
5659d) filament winding
5660269
5661e) open mold process
566290. Copper is a relatively easy metal to weld because its thermal conductivity is high:
5663a) true
5664b) false
566591. Metals that are easiest to weld in resistance welding are ones that have low resistivities since low
5666resistivity assists in the flow of electrical current:
5667a) true
5668b) false
566992. Which one of the following arc-welding processes produces the highest temperatures?
5670a) CAW
5671b) PAW
5672c) SAW
5673d) TIG
567493. MIG welding is a term sometimes applied when referring to which one of the following processes?
5675a) SMAW
5676b) GMAW
5677c) GTAW
5678d) SAW
567994. Which of the following processes are classified as fusion welding (three correct answers)?:
5680a) electrogas welding
5681270
5682b) electron-beam welding
5683c) explosion welding
5684d) forge welding
5685e) laserbeam welding
5686f) ultrasonic welding
568795. Welding can only be performed on metals that have the same melting point; otherwise, the metal
5688with the lower melting temperature always melts while the other metal remains solid:
5689a) true
5690b) false
569196. The holding force in cup-drawing is most likely to be
5692a) greater than the maximum cup-drawing force
5693b) equal to the maximum cup-drawing force
5694c) less than the maximum cup-drawing force
569597. Which of the following processes are classified as high-energy-rate forming processes (two best answers):
5696a) electrochemical machining
5697b) electromagnetic forming
5698c) electron beam cutting
5699d) explosive forming
5700e) Guerin process
5701f) hydroforming
5702g) redrawing
5703h) shear spinning
5704271
570598. Which of the following are variations of sheet-metal-bending operations (two best answers):
5706a) flanging
5707b) hemming
5708c) ironing
5709d) notching
5710e) shear spinning
5711f) trimming
5712g) tube bending
571399. Springback in a sheet-metal-bending operation is the result of which one of the following?:
5714a) elastic modulus of the metal
5715b) elastic recovery of the metal
5716c) overbending
5717d) overstraining
5718e) yield strength of the metal
5719100. Which one of the following is the best definition of bend allowance?:
5720a) amount by which the die is larger than the punch
5721b) amount of elastic recovery experienced by the metal after bending
5722c) safety factor used in calculating bending force
5723d) length of the straight sheetmetal section to be bent, before bending
5724Fundamentals of Manufacturing Processes
57251. Directional solidification in castings can be improved using
5726272
5727a) chills and chaplets
5728b) chills and padding
5729c) chaplets and padding
5730d) chills, chaplets and padding
57312. Misrun is a casting defect which occurs due to
5732a) very high pouring temperature of the metal
5733b) insufficient fluidity of the molten metal
5734c) absorption of gases by the liquid metal.
5735d) improper alignment of the mould flasks
57363. Which of the following pairs are correctly matched?
5737(1) Pit moulding...for large jobs
5738(2) Investment casting...Lost wax process
5739(3) Plaster moulding...Mould prepared in gypsum
5740a) 1, 2 and 3
5741b) 1 and 2
5742c) 1 and 3
5743d) 2 and 3
57444. If the melting ratio of a cupola is 10:1, then the coke requirement for one ton melt will be
5745a) 0.1 ton
5746b) 10 tons
5747c) 1 ton
5748d) 11 tons
57495. Which of the following are the requirements of an ideal gating system?
5750273
57511.The molten metal should enter the mould cavity with maximum possible velocity.
57522. It should facilitate complete filling of the mould cavity.
57533. It should be able to prevent the flowing molten metal from absorbing the air or gases from surroundings
5754a) 1,2 and 3
5755b) 1 and 2
5756c) 2 and 3
5757d) 1 and 3
57586. A spherical drop of molten metal of radius 2 mm is found to solidify in 10 seconds. A similar drop of radius 4 mm would solidify in
5759a) 14.14 seconds
5760b) 20 seconds
5761c) 18.3 seconds
5762d) 40 seconds
57637. During solidification of a casting, the compensation for solid contraction is
5764a) Provided by the oversize pattern
5765b) Achieved by properly placed risers.
5766c) Obtained by promoting direction solidification.
5767d) Made by providing chills
57688. The main purpose of chaplets is
5769a) To ensure directional solidification
5770b) To provide efficient venting
5771c) For aligning the mould boxes
5772d) To support the cores
5773274
57749. Which one of the following processes produce a casting where the pressure forces the molten metal into the mould cavity?
5775a) Shell moulding
5776b) Investment casting
5777c) Die casting
5778d) Continuous casting
577910. Shell moulding can be used for
5780a) producing milling cutters
5781b) making gold ornaments
5782c) producing heavy and thick walled casting
5783d) producing thin casting
578411. In liquid-state welding process, the zones formed are
5785a) gas sheilded zone, fusion zone, and unaffected original base metal zone
5786b) liquid zone, fusion zone and heat afftected unmelted zone
5787c) liquid-shielded zone, gas-shielded zone and flux-metal reactive zone
5788d) fusion zone, heat affected unmelted zone and unaffected original base metal zone
578912. Weldability depends on
5790a) Thermal conductivity and Surface condition only
5791b) Thermal conductivity and Change in microstructure only.
5792c) Thermal conductivity, Surface condition and Change in microstructure
5793d) Surface condition and Change in microstructure only
579413. The advantage of metal welding process is
5795a) It relieves the joint from residual stresses
5796275
5797b) It helps in checking of distortion of work piece
5798c) Large number of metals and alloys, both similar and / or dissimilar can be joined
5799d) Heat produced during the welding does not produce metallurgical changes
580014. Brittle welds are mainly obtained due to
5801a) Wrong electrode, faulty prheating and metal hardened by air
5802b) Faulty welds, faulty sequence and rigid joints
5803c) Wrong welding speed, current improperly adjusted and faulty preparation
5804d) Uneven heat, improper sequence and deposited metal shrinks
580515. Which of the following factors improves weldability of steel?
5806a) Low carbon content and Good affinity to oxygen
5807b) High carbon content and Good affinity to oxygen
5808c) Low carbon content and Poor affinity to oxygen
5809d) High carbon content and Poor affinity to oxygen
581016. In arc welding, the arc length should be equal to
5811a) 4.5 times the rod diameter
5812b) 3 times the rod diameter
5813c) 1.5 times the rod diameter
5814d) Rod diameter
581517. In an inert gas welding process, the commonly used gas is
5816a) Hydrogen
5817b) Oxygen
5818c) Helium or Argon
5819d) Krypton
5820276
582118. Good example for the application of friction welding can be
5822a) Uniting large-area sheets
5823b) Welding a rod to a flat surface
5824c) Fabrication of nuclear reactor components
5825d) Welding of very thin metal parts
582619. By which of the following welding process, gray-iron is usally welded?
5827a) TIG welding (GTAW)
5828b) MIG welding (GMAW)
5829c) Gas welding
5830d) Arc welding
583120. Best example for the application of explosive welding is
5832a) Welding a rod to a flat surface
5833b) Fabrication of nuclear reactor components
5834c) Welding very thin metal parts
5835d) Uniting large-area sheets
583621. A toothpaste tube can be produced by
5837a) solid forward extrusion
5838b) solid backward extrusion
5839c) hallow backward extrusion
5840d) solid forward extrusion
584122. In hot die forging, thin layer of material all around the forging is
5842a) gutter space, which fills up hot gases
5843277
5844b) flash, the width of ti is an indicator of the pressure developed in the cavity
5845c) coining, which indicates the quality of forging
5846d) cavity, which is filled with hot impurities in the material
584723. Extrusion process can effectively reduce the cost of product through
5848a) Material saving
5849b) Process time saving
5850c) Saving in tooling cost
5851d) Saving in adminstrative cost
585224. Which of the following is a high energy rate forming process?
5853a) Roll forming
5854b) Electrohydraulic forming
5855c) Rotary forging
5856d) Forward extrusion
585725. Which of the folowing stresses is involved in wire drawing process?
5858a) Compressive only
5859b) Tensile only
5860c) A combination of tensile and compressive stresses
5861d) A combination of tensile, compressive and shear stresses
586226. Which one of the following is NOT a high energy rate forming process?
5863a) Electro-magnetic
5864b) Roll-forming
5865c) Explosive forming
5866d) Electro-hydraulic forming
5867278
586827. Which of the following metal forming process is used for manufacture of long steel wire?
5869a) Deep drawing
5870b) Drawing
5871c) Forging
5872d) Extrusion
587328. Which of the following properties do the hydrostatic pressure in extrusion process improve
5874a) Ductility
5875b) Compressive strength
5876c) Brittleness
5877d) Tensile strength
587829. The process of removing burrs or flash from a forged component in drop forging is called
5879a) Swaging
5880b) Peroforating
5881c) Trimming
5882d) Fettling
588330. In a forging operation, fullering is done to
5884a) draw out the material
5885b) bend the material
5886c) upset the material
5887d) extrude the material
588831. In the rolling process, roll separating force can be decreased by
5889279
5890a) reducing the roll diameter
5891b) increasing the roll diameter
5892c) providing back-up rolls
5893d) increasing friction between the rolls and the material
589432. Best position of crank for blanking operation in a mechanical press is
5895a) top dead centre
5896b) 20 degrees below the tdc
5897c) 20 degrees before the bottom dead centre
5898d) bottom dead centre
589933. Which of the following is the correct temperature range for hot extrusion of aluminium?
5900a) 300-400 deg C
5901b) 350-400 deg C
5902c) 430-480 deg C
5903d) 550-600 deg C
590434. Which of the following metal forming process is associated with the term 'camber'?
5905a) Drawing
5906b) Rolling
5907c) Wire drawing
5908d) Sheet metal forming
590935. Which of the following metal forming process has the associated term 'Pilots'?
5910a) Drawing
5911b) Rolling
5912c) wire drawing
5913280
5914d) Sheet metal forming
591536. Which one of the following metal forming process has the associated term 'soap solutions'?
5916a) Drawing
5917b) Rolling
5918c) Wire drawing
5919d) Sheet metal forming
592037. Which one of the following is an advantage of the forging process?
5921a) Good surface finish
5922b) Low tooling cost
5923c) Close tolerance
5924d) Improved physical property
592538. In the wire drawing process, a bright shining surface on the output wire is obtained if one
5926a) is not using a lubricant
5927b) is using a lubricant
5928c) uses thick paste lubricant
5929d) uses thin fluid lubricant
593039. The defect 'chevron cracks' is associated with the following metal forming process,
5931a) Drawing
5932b) Extrusion
5933c) Sheet metal forming
5934d) forging
5935281
593640. Metal surfaces having higher hardness & fatigue strength can best be obtained by
5937a) Roll forming
5938b) Shot peening
5939c) Forging
5940d) Cold forming
5941282
5942Heat and Mass Transfer
59431. The internal energy of an ideal gas is a function of
5944a) temperature and pressure
5945b) volume and pressure
5946c) volume and pressure
5947d) temperature only
59482. Consider one-dimensional steady state heat conduction, without heat generation, in a plane wall; with boundary conditions as shown in the figure below. The conductivity of the wall is given by k = k0 + bT ; where k0 and b are positive constants, and T is temperature.
5949As x increases, the temperature gradient ( dT/dx ) will
5950a) remain constant
5951b) be zero
5952c) increase
5953d) decrease
59543. Consider one-dimensional steady state heat conduction along x-axis (0 ≤ x ≤ L), through a plane wall with the boundary surfaces (x=0 and x=L) maintained at temperatures of 0°C and 100°C. Heat is generated uniformly throughout the wall. Choose the CORRECT statement.
5955a) The direction of heat transfer will be from the surface at 100°C to the surface at 0°C.
5956b) The maximum temperature inside the wall must be greater than 100°C.
5957c) The temperature distribution is linear within the wall.
5958d) The temperature distribution is symmetric about the mid-plane of the wall.
59594. A steel ball of diameter 60 mm is initially in thermal equilibrium at 1030°C in a furnace. It is suddenly removed from the furnace and cooled in ambient air at 30°C, with convective heat transfer coefficient h = 20 W/m2K. The thermo-physical properties of steel are: density ρ = 7800 kg/m3, conductivity k = 40 W/mK and specific heat c = 600 J/kgK. The time required in seconds to cool the steel ball in air from 1030°C to 430°C is
5960283
5961a) 519
5962b) 931
5963c) 1195
5964d) 2144
59655. Two large diffuse gray parallel plates, separated by a small distance, have surface temperatures of 400 K and 300 K. If the emissivities of the surfaces are 0.8 and the Stefan-Boltzmann constant is 5.67 × 10-8W/m2K4, the net radiation heat exchange rate in kW/m2 between the two plates is
5966a) 0.66
5967b) 0.79
5968c) 0.99
5969d) 0.87
59706. Which one of the following configurations has the highest fin effectiveness?
5971a) Thin, closely spaced fins
5972b) Thin, widely spaced fins
5973c) Thick, widely spaced fins
5974d) Thick, closely spaced fins
59757. Water (Cp = 4.18 kJ/kg.K) at 80°C enters a counterflow heat exchanger with a mass flow rate of 0.5 kg/s. Air (Cp = 1kJ/kg.K) enters at 30°C with a mass flow rate of 2.09 kg/s. If the effectiveness of the heat exchanger is 0.8, the LMTD (in °C) is
5976a) 7
5977b) 4
5978c) 10
5979d) 8
5980284
59818. In a condenser of a power plant, the steam condenses at a temperature of 60oC. The cooling water enters at 30°C and leaves at 45°C. The logarithmic mean temperature difference (LMTD) of the condenser is
5982a) 16.2° C
5983b) 21.6° C
5984c) 30° C
5985d) 37.5° C
59869. A pipe of 25 mm outer diameter carries steam. The heat transfer coefficient between the cylinder and surroundings is 5 W/m2 K. It is proposed to reduce the heat loss from the pipe by adding insulation having a thermal conductivity of 0.05 W/mK. Which one of the following statements is TRUE?
5987a) The outer radius of the pipe is equal to the critical radius
5988b) The outer radius of the pipe is less than the critical radius
5989c) Adding the insulation will reduce the heat loss
5990d) Adding the insulation will increase the heat loss
599110. A spherical steel ball of 12 mm diameter is initially at 1000 K. It is slowly cooled in a surrounding of 300K. The heat transfer coefficient between the steel ball and the surrounding is 5 W/m2 K. The thermal conductivity of steel is 20 W/mK. The temperature difference between the centre and the surface of the steel ball is
5992a) large because conduction resistance is far higher than the convective resistance
5993b) large because conduction resistance is far less than the convective resistance
5994c) small because conduction resistance is far higher than the convective resistance
5995d) small because conduction resistance is far less than the convective resistance
5996285
5997Heat and Mass Transfer - MEE303
59981. A solid sphere and a hollow sphere of the same material and size are heated to the same temperature and allowed to cool in the same surroundings. If the temperature difference between the body and that of the surrounding is T, then
5999a) The hollow sphere will cool at a faster rate for all the values of T
6000b) Both the spheres will cool at the same rate for small values of T
6001c) Both the spheres will cool at the same rate for all values of T
6002d) The solid sphere will cool at a faster rate for all the values of T
60032. A furnace is made of a red brick wall of thickness 0.5 m and conductivity 0.7 W/mK. For the same heat loss and the temperature drop, this can be replaced by a layer of diatomite earth of conductivity of 0.14 W/mK and thickness should be
6004a) 0.5 m
6005b) 0.1 m
6006c) 0.2 m
6007d) 0.4 m
60083. Heat transfer takes place according to the statement of
6009a) Zeroth Law of Thermodynamics
6010b) First Law of Thermodynamics
6011c) Second Law of Thermodynamics
6012d) Third Law of Thermodynamics
60134. In a long cylindrical rod of radius R and a surface heat flux of Q, the uniform internal heat generation rate is
6014a) Q/R
6015b) 2Q/R
6016c) 3Q/R
6017286
6018d) 4Q/R
60195. For a current carrying metallic ball of 20 mm diameter exposed to air (h=25 W/m2K), maximum heat distribution occurs when the thickness of the insulation (K=0.5 W/mK) is
6020a) 10 mm
6021b) 20 mm
6022c) 30 mm
6023d) 40 mm
60246. Consider the following statements:
60251. Under certain conditions, an increase in thickness of insulation may increase the heat loss from a heated pipe.
60262. The heat loss from an insulated pipe reaches a maximum when the outside radius insulation is equal to the ratio of thermal conductivity to surface coefficient.
60273. Small diameter tubes are invariably insulated.
60284. For a steam pipe economic insulation is based on minimum heat loss from pipe.
6029a) 1 and 3
6030b) 2 and 4
6031c) 3 and 4
6032d) 1 and 2
60337. Consider the following statements:
6034The Fourier Heat conduction equation presumes:
60351. Steady state conditions.
60362. Constant value of thermal conductivity.
60373. Uniform temperatures at the wall surfaces.
60384. One-dimensional heat flow.
6039Of these statements, the correct statements are
6040287
6041a) 1, 2 and 3
6042b) 1, 2 and 4
6043c) 1, 3 and 4
6044d) 2, 3 and 4
60458. Two insulating materials of thermal conductivity k and 2k are available for lagging a pipe carrying a hot fluid. If the radial thickness of each material is the same
6046a) Material with higher thermal conductivity should be used for inner layer and one with lower thermal conductivity for the outer.
6047b) It is immaterial in which sequence the insulating materials are used.
6048c) It is not possible to judge unless numerical values of dimensions are given.
6049d) Material with lower thermal conductivity should be used for inner layer and one with higher thermal conductivity for the outer.
60509. A solid wall conducts 45 W of heat. It is desired to reduce the heat transfer rate to 15W by changing only the wall thickness. Then the thickness of the wall, now should be
6051a) 1/3rd of the original
6052b) 6 times the original
6053c) 3 times the original
6054d) 1/6th of the original
605510. Heat is lost through a brick wall (k=0.72W/mK), which is 4m long, 3m wide, and 25cm thick at a rate of 500W. If the inner surface of the wall is at 22 oC, the temperature at the midplane of the wall is
6056a) 0.8 oC
6057b) 11.3 oC
6058c) 14.8 oC
6059d) 22.1 oC
6060288
606111. Consider two different materials A and B. The ratio of thermal conductivities of A and B is 13, the ratios of densities of A and B is 0.045 and the ratio of specific heats of A and B is 16.90. Then the ratio of thermal diffusivities of A to B is
6062a) 17.1
6063b) 16.1
6064c) 13.3
6065d) 10.6
606612. A gas filled tube has 2 mm inside diameter and 25 cm length. The gas is heated by an electrical wire of diameter 50 μm located along the axis of the tube. Current and voltage drop across the heating element are 0.5 amps and 4 volts, respectively. If the measured wire and inside tube wall temperatures are 175 oC and 150 oC respectively, find the thermal conductivity of the gas filling tube
6067a) 0.12 W/m.K
6068b) 0.15 W/m.K
6069c) 0.16 W/m.K
6070d) 0.19 W/m.K
607113. Electric current is passed through a copper ball 1 mm in diameter. The ball is submerged in liquid water at atmospheric pressure, and the current is increased until the water boils. For this situation h = 5000 W/m2.K. How much electric power must be supplied to the wire to maintain the ball at 114 oC?
6072a) 0.2199 W
6073b) 21.99 W
6074c) 25.64 W
6075d) 0.2564 W
607614. Which of the following is having same dimensions as Thermal diffusivity
6077a) Thermal conductivity
6078b) kinematic viscosity
6079289
6080c) dynamic viscosity
6081d) heat capacity
608215. A 3-cm-long, 2 mm × 2 mm rectangular cross-section aluminum fin (k = 237 W/m⋅ºC) is attached to a surface. If the fin efficiency is 65 percent, the effectiveness of this single fin is
6083a) 30
6084b) kinematic viscosity
6085c) dynamic viscosity
6086d) heat capacity
608716. Which of the following materials have low temperature gradient for same thickness of the slab
6088a) silver
6089b) copper
6090c) alumnum
6091d) carbon steel
609217. Radial heat transfer rate through hollow cylinder decreases as the ratio of outer to inner radius
6093a) decreases
6094b) increases
6095c) constant
6096d) can not predict
609718. From a metallic wall at 100 oC, a metallic rod protrudes to the ambient air. The temperature at the tip will be minimum when the rod is made of
6098a) aluminum
6099b) gold
6100290
6101c) diamond
6102d) silver
610319. Which of the following is correct with respect to thermal conductivity (k) of material
6104a) kgases > Kinsulators > Kliquids
6105b) kgases = Kinsulators = Kliquids
6106c) both a & b
6107d) kgases<Kinsulators<Kliquids
610820. A steel ball of mass 1kg and specific heat 0.4 kJ/kg is at a temperature of 60°C. It is dropped into 1kg water at 20°C. The final steady state temperature of water is
6109a) 23.5°C
6110b) 32.3°C
6111c) 13.5°C
6112d) 42.1°C
611321. In current carrying conductors, if the radius of the conductor is less than the critical radius, then addition of electrical insulation is desirable, as
6114a) It reduces the heat loss from the conductor and thereby enables the
6115conductor to carry a higher current.
6116b) It increases the heat loss from the conductor and thereby enables the
6117conductor to carry a higher current.
6118c) It increases the thermal resistance of the insulation and thereby enables the
6119conductor to carry a higher current.
6120d) It reduces the thermal resistance of the insulation and thereby enables the
6121conductor to carry a higher current.
6122291
612322. A steam pipe is to be lined with two layers of insulating materials of different thermal conductivities. For minimum heat transfer
6124a) The better insulation must be put inside
6125b) The better insulation must be put outside
6126c) One could place either insulation on either side
6127d) One should take into account the steam temperature before deciding as to which insulation is put where.
612823. In order to substantially reduce leakage of heat from atmosphere into cold refrigerant flowing in small diameter copper tubes in a refrigerant system, the radial thickness of insulation, cylindrically wrapped
6129around the tubes, must be:
6130a) Higher than critical radius of insulation
6131b) Slightly lower than critical radius of insulation
6132c) Equal to the critical radius of insulation
6133d) Considerably higher than critical radius of insulation
613424. From a metallic wall at 100°C, a metallic rod protrudes to the ambient air. The temperatures at the tip will be minimum when the rod is made of:
6135a) Aluminum
6136b) Steel
6137c) Copper
6138d) Silver
613925. Provision of fins on a given heat transfer surface will be more it there are:
6140a) Fewer number of thick fins
6141b) Fewer number of thin fins
6142c) Large number of thin fins
6143d) Large number of thick fins
6144292
614526. In order to achieve maximum heat dissipation, the fin should be designed in such a way that:
6146a) It should have maximum lateral surface at the root side of the fin
6147b) It should have maximum lateral surface towards the tip side of the fin
6148c) It should have maximum lateral surface near the centre of the fin
6149d) It should have minimum lateral surface near the centre of the fin
615027. Consider the following statements pertaining to large heat transfer rate using fins:
61511. Fins should be used on the side where heat transfer coefficient is small
61522. Long and thick fins should be used
61533. Short and thin fins should be used
61544. Thermal conductivity of fin material should be large
6155Which of the above statements are correct?
6156a) 1, 2 and 3
6157b) 1, 2 and 4
6158c) 2, 3 and 4
6159d) 1, 3 and 4
616028. Consider the following statements pertaining to heat transfer through fins:
61611. Fins are equally effective irrespective of whether they are on the hot side or cold side of the fluid.
61622. The temperature along the fin is variable and hence the rate of heat transfer varies along the elements of the fin.
61633. The fins may be made of materials that have a higher thermal conductivity than the material of the wall.
61644. Fins must be arranged at right angles to the direction of flow of the working fluid.
6165Of these statements:
6166293
6167a) 1 and 2 are correct
6168b) 2 and 4 are correct
6169c) 1 and 3 are correct
6170d) 2 and 3 are correct
617129. The value of Biot number is very small (less than 0.01) when
6172a) The convective resistance of the fluid is negligible
6173b) The conductive resistance of the fluid is negligible
6174c) The conductive resistance of the solid is negligible
6175d) None of these
617630. A spherical thermocouple junction of diameter 0.706 mm is to be used for the measurement of temperature of a gas stream. The convective heat transfer co-efficient on the bead surface
6177is 400 W/m2K. Thermophysical properties of thermocouple material are k = 20 W/mK, C =400 J/kg, K and ρ = 8500 kg/m3. If the thermocouple initially at 30°C is placed in a hot stream
6178of 300°C, then time taken by the bead to reach 298°C, is:
6179a) 2.35 s
6180b) 4.9 s
6181c) 14.7 s
6182d) 29.4 s
618331. A small copper ball of 5 mm diameter at 500 K is dropped into an oil bath whose temperature is 300 K. The thermal conductivity of copper is 400 W/mK, its density 9000 kg/m3 and its
6184specific heat 385 J/kg.K.1f the heat transfer coefficient is 250 W/m2K. What will be the value of Biot number?
6185a) 0.0005208
6186b) 0.00123
6187294
6188c) 0.004923
6189d) 0.0093234
619032. Which one of the following statements is correct? The curve for unsteady state cooling or heating of bodies
6191a) Parabolic curve asymptotic to time axis
6192b) Exponential curve asymptotic to time axis
6193c) Exponential curve asymptotic both to time and temperature axis
6194d) Hyperbolic curve asymptotic both to time and temperature axis
619533. A thermocouple in a thermo-well measures the temperature of hot gas flowing through the pipe. For the most accurate measurement of temperature, the thermo-well should be made of:
6196a) Steel
6197b) Brass
6198c) Copper
6199d) Aluminum
620034. Heisler charts are used to determine transient heat flow rate and temperature distribution when:
6201a) Solids possess infinitely large thermal conductivity
6202b) Internal conduction resistance is small and convective resistance is large
6203c) Internal conduction resistance is large and the convective resistance is small
6204d) Both conduction and convention resistance are almost of equal significance
620535. Assertion (A): During the temperature measurement of hot gas in a duct that has relatively cool walls, the temperature indicated by the thermometer will be lower than the true hot gas
6206temperature. Reason(R): The sensing tip of thermometer receives energy from the hot gas and loses heat to the duct walls.
6207295
6208a) Both A and R are individually true and R is the correct explanation of A
6209b) Both A and R are individually true but R is not the correct explanation of A
6210c) A is true but R is false
6211d) A is false but R is true
621236. The Biot number can be thought of as the ratio of
6213a) the conduction thermal resistance to the convective thermal resistance.
6214b) the convective thermal resistance to the conduction thermal resistance.
6215c) The thermal energy storage capacity to the conduction thermal resistance.
6216d) The thermal energy storage capacity to the convection thermal resistance.
621737. Heating or Cooling of a road surface can be analysed using
6218a) lumped parameter model
6219b) Infinite slab model
6220c) Semi infinite slab model
6221d) none of these
622238. Choose the correct statement, Semi infinite model can be adopted when
6223a) thickness of the solid is very large
6224b) heat diffusion is very slow
6225c) short time period
6226d) all of these
622739. A 320 cm high vertical pipe at 15 oC wall temperature is in a room with still air at 10 oC. This pipe supplies heat at the rate of 8 kW into room air by natural convection. Assuming laminar flow, the height of the pipe needed to supply 1 kW only is
6228a) 10 cm
6229b) 20 cm
6230296
6231c) 40 cm
6232d) 80 cm
623340. Free convection flow depends on all of the following except
6234a) Density
6235b) Coefficient of viscosity
6236c) Gravity
6237d) Velocity
623841. Peclet number is the product of _______________ number and ______________ number.
6239a) Reynolds, Nusselt
6240b) Reynolds, Prandtl
6241c) Nusselt, Reynolds
6242d) Nusselt, Grasshoff
624342. In bank of tubes, heat transfer will be highest when arrangement is
6244a) Linear with lower longitudinal pitch
6245b) Staggered with lower longitudinal pitch
6246c) Staggered equal pitch
6247d) Linear with square pitch
624843. The thickness of thermal and hydrodynamic boundary layer is equal if
6249a) Prandtl Number = Nusselt Number
6250b) Prandtl Number = 1
6251c) Nusselt Number = 1
6252d) Grashoff Number = 1
6253297
625444. If velocity of water inside a smooth tube is doubled, then turbulent flow heat transfer coefficient between the water and the tube will:
6255a) Remain unchanged
6256b) Increase to double its value
6257c) Increase but will not reach double its value
6258d) Increase to more than double its value
625945. A sphere, a cube and a thin circular plate, all made of same material and having same mass are initially heated to a temperature of 250 oC and then left in air at room temperature for
6260cooling. Then, which one of the following is correct?
6261a) All will be cooled at the same rate
6262b) Circular plate will be cooled at lowest rate
6263c) Sphere will be cooled faster
6264d) Cube will be cooled faster than sphere but slower than circular plate
626546. A thin flat plate 2 m by 2 m is hanging freely in air. The temperature of the surroundings is 25°C. Solar radiation is falling on one side of the rate at the rate of 500 W/m2. The temperature
6266of the plate will remain constant at 30°C, if the convective heat transfer coefficient (in W/m2 °C) is:
6267a) 25
6268b) 50
6269c) 100
6270d) 200
627147. Air at 20°C blows over a hot plate of 50 × 60 cm made of carbon steel maintained at 220°C. The convective heat transfer coefficient is 25 W/m2K. What will be the heat loss from the plate?
6272a) 1500 W
6273298
6274b) 2500 W
6275c) 3000 W
6276d) 4000 W
627748. For calculation of heat transfer by natural convection from a horizontal cylinder, what is the characteristic length in Grashof Number?
6278a) Diameter of the cylinder
6279b) Length of the cylinder
6280c) Circumference of the base of the cylinder
6281d) Half the circumference of the base of the cylinder
628249. Assertion (A): For the similar conditions the values of convection heat transfer coefficients are more in forced convection than in free convection.
6283Reason (R): In case of forced convection system the movement of fluid is by means of external agency.
6284a) Both A and R are individually true and R is the correct explanation of A
6285b) Both A and R individually true but R in not the correct explanation of A
6286c) A is true but R is false
6287d) A is false but R is true
628850. The properties of mercury at 300 K are: density = 13529 kg/m3, specific heat at constant pressure = 0.1393 kJ/kg-K, dynamic viscosity = 0.001523 N.s/m2 and thermal conductivity =
62898.540 W/mK. The Prandtl number of the mercury at 300 K is:
6290a) 0.0248
6291b) 2.48
6292c) 24.8
6293d) 248
6294299
629551. Assertion (A): A slab of finite thickness heated on one side and held horizontal will lose more heat per unit time to the cooler air if the hot surface faces upwards when compared with the
6296case where the hot surface faces downwards.
6297Reason (R): When the hot surface faces upwards, convection takes place easily whereas when the hot surface faces downwards, heat transfer is mainly by conduction through air.
6298a) Both A and R are individually true and R is the correct explanation of A
6299b) Both A and R are individually true but R is not the correct explanation of A
6300c) A is true but R is false
6301d) A is false but R is true
630252. Heat is lost from a 100 mm diameter steam pipe placed horizontally in ambient at 30°C. If the Nusselt number is 25 and thermal conductivity of air is 0.03 W/mK, then the heat transfer co-efficient in W/m2.K will be:
6303a) 7.5
6304b) 16.2
6305c) 25.2
6306d) 30
630753. Which one of the following non-dimensional numbers is used for transition from laminar to turbulent flow in free convection?
6308a) Reynolds number
6309b) Grashoff number
6310c) Peclet number
6311d) Rayleigh number
631254. Which one of the following numbers represents the ratio of kinematic viscosity to the thermal diffusivity?
6313a) Gashoff number
6314b) Prandtl number
6315300
6316c) Mach number
6317d) Nusselt number
631855. Nusselt number for a pipe flow heat transfer coefficient is given by the equation NuD = 4.36. Which one of the following combinations of conditions does exactly apply for use of this equation?
6319a) Laminar flow and constant wall temperature
6320b) Turbulent flow and constant wall heat flux
6321c) Turbulent flow and constant wall temperature
6322d) Laminar flow and constant wall heat flux
632356. A 320 cm high vertical pipe at 150°C wall temperature is in a room with still air at 10°C. This pipe supplies heat at the rate of 8 kW into the room air by natural convection. Assuming
6324laminar flow, the height of the pipe needed to supply 1 kW only is:
6325a) 10 cm
6326b) 20 cm
6327c) 40 cm
6328d) 80 cm
632957. Natural convection heat transfer coefficients over surface of a vertical pipe and vertical flat plate for same height and fluid are equal. What is/are the possible reasons for this?
63301. Same height
63312. Both vertical
63323. Same fluid
63334. Same fluid flow pattern
6334Select the correct answer using the code given below:
6335a) 1 only
6336b) 1 and 2
6337301
6338c) 3 and 4
6339d) 4 only
634058. The average Nusselt number in laminar natural convection from a vertical wall at 180°C with still air at 20°C is found to be 48. If the wall temperature becomes 30°C, all other parameters
6341remaining same, the average Nusselt number will be:
6342a) 8
6343b) 16
6344c) 24
6345d) 32
634659. The ratio of energy transferred by convection to that by conduction is called
6347a) Stanton number
6348b) Nusselt number
6349c) Biot number
6350d) Peclet number
635160. Consider the following phenomena:
63521. Boiling
63532. Free convection in air
63543. Forced convection
63554. Conduction in air
6356Their correct sequence in increasing order of heat transfer coefficient is:
6357a) 4, 2, 3, 1
6358b) 4, 1, 3, 2
6359c) 4, 3, 2, 1
6360d) 3, 4, 1, 2
6361302
636261. Consider the following statements regarding condensation heat transfer:
63631. For a single tube, horizontal position is preferred over vertical position for better heat transfer.
63642. Heat transfer coefficient decreases if the vapour stream moves at high velocity.
63653. Condensation of steam on an oily surface is dropwise.
63664. Condensation of pure benzene vapour is always dropwise.
6367Of these statements
6368a) 1 and 2 are correct
6369b) 2 and 4 are correct
6370c) 1 and 3 are correct
6371d) 3 and 4 are correct
637262. When all the conditions are identical, in the case of flow through pipes with heat transfer, the velocity profiles will be identical for:
6373a) Liquid heating and liquid cooling
6374b) Gas heating and gas cooling
6375c) Liquid heating and gas cooling
6376d) Heating and cooling of any fluid
637763. Drop wise condensation usually occurs on
6378a) Glazed surface
6379b) Smooth surface
6380c) Oily surface
6381d) Coated surface
638264. Consider the following statements regarding nucleate boiling:
63831. The temperature of the surface is greater than the saturation temperature of the liquid.
6384303
63852. Bubbles are created by the expansion of entrapped gas or vapour at small cavities in the surface.
63863. The temperature is greater than that of film boiling.
63874. The heat transfer from the surface to the liquid is greater than that in film boiling.
6388Of these correct statements are:
6389a) 1, 2 and 4
6390b) 1 and 3
6391c) 1, 2 and 3
6392d) 2, 3 and 4
639365. In spite of large heat transfer coefficients in boiling liquids, fins are used advantageously when the entire surface is exposed to:
6394a) Nucleate boiling
6395b) Film boiling
6396c) Transition boiling
6397d) All modes of boiling
639866. When a liquid flows through a tube with sub-cooled or saturated boiling, what is the process known?
6399a) Pool boiling
6400b) Bulk boiling
6401c) Convection boiling
6402d) Forced convection boiling
640367. For film-wise condensation on a vertical plane, the film thickness δ and heat transfer coefficient h vary with distance x from the leading edge as
6404a) δ decreases, h increases
6405b) Both δ and h increase
6406304
6407c) δ increases, h decreases
6408d) Both δ and h decrease
640968. Saturated steam is allowed to condense over a vertical flat surface and the condensate film flows down the surface. The local heat transfer coefficient for condensation
6410a) Remains constant at all locations of the surface
6411b) Decreases with increasing distance from the top of the surface
6412c) Increases with increasing thickness of condensate film
6413d) Increases with decreasing temperature differential between the surface and
6414vapour
641569. Consider the following statements:
64161. If a condensing liquid does not wet a surface drop wise, then condensation will take place on it.
64172. Drop wise condensation gives a higher heat transfer rate than filmwise condensation.
64183. Reynolds number of condensing liquid is based on its mass flow rate.
64194. Suitable coating or vapour additive is used to promote film-wise condensation.
6420Of these statements:
6421a) 1 and 2 are correct
6422b) 2, 3 and 4 are correct
6423c) 4 alone is correct
6424d) 1, 2 and 3 are correct
642570. A hollow encloser is formed between two infinitely long concentric cylinders of radii 1 m ans 2 m, respectively. Radiative heat exchange takes place between the inner surface of the
6426larger cylinder (surface-2) and the outer surface of the smaller cylinder (surface- I). The radiating surfaces are diffuse and the medium in the enclosure is non-participating. The fraction of
6427the thermal radiation leaving the larger surface and striking itself is:
6428305
6429a) 0.25
6430b) 0.5
6431c) 0.75
6432d) 1
643371. The shape factors with themselves of two infinity long black body concentric cylinders with a diameter ratio of 3 are ___________ for the inner and ________________ for the outer.
6434a) 0, 2/3
6435b) 0, 1/3
6436c) 1, 1/9
6437d) 1, 1/3
643872. The radiative heat transfer rate per unit area (W/m2) between two plane parallel grey surfaces (emissivity = 0.9) maintained at 400 K and 300 K is:
6439(Stefan Boltzman constant. σ = 5.67 × 10–8 W/m2 K4)
6440a) 992
6441b) 812
6442c) 464
6443d) 567
644473. Fraction of radiative energy leaving one surface that strikes the other surface is called
6445a) Radiative flux
6446b) Emissive power of the first surface
6447c) View factor
6448d) Re-radiation flux
6449306
645074. Assertion (A): Heat transfer at high temperature is dominated by radiation rather than convection.
6451Reason (R): Radiation depends on fourth power of temperature while convection depends on unit power relationship.
6452a) Both A and R are individually true and R is the correct explanation of A
6453b) Both A and R are individually true but R is not the of A
6454c) A is true but R is false
6455d) A is false but R is true
645675. Consider following parameters:
64571. Temperature of the surface
64582. Emissivity of the surface
64593. Temperature of the air in the room
64604. Length and diameter of the pipe
6461The parameter(s) responsible for loss of heat from a hot pipe surface in a room without fans would include
6462a) 1 alone
6463b) 1 and 2
6464c) 1, 2 and 3
6465d) 1, 2, 3 and 4
646676. When α is absorbtivity, ρ is reflectivity and τ is transmisivity, then for diathermanous body, which of the following relation is valid?
6467a) α = 1, ρ = 0, τ = 0
6468b) α = 0, ρ = 1, τ = 0
6469c) α = 0, ρ = 0, τ = 1
6470d) α + ρ = 1, τ = 0
6471307
647277. If the temperature of a solid state changes from 27°C to 627°C, then emissive power changes which rate
6473a) 6 : 1
6474b) 9 : 1
6475c) 27 : 1
6476d) 81 : 1
647778. An enclosure consists of the four surfaces 1, 2, 3 and 4. The view factors for radiation heat transfer (where the subscripts 1, 2, 3, 4 refer to the respective surfaces) are F11 = 0.1, F12 =
64780.4 and F13 = 0.25. The surface areas A1 and A4 are 4 m2 and 2 m2 respectively. The view factor F41 is:
6479a) 0.75
6480b) 0.5
6481c) 0.25
6482d) 0.1
648379. Two long parallel surfaces, each of emissivity 0.7 are maintained at different temperatures and accordingly have radiation exchange between them. It is desired to reduce 75% of this
6484radiant heat transfer by inserting thin parallel shields of equal emissivity (0.7) on both sides.
6485What would be the number of shields?
6486a) 1
6487b) 2
6488c) 3
6489d) 4
649080. For an opaque plane surface the irradiation, radiosity and emissive power are respectively 20, 12 and 10 W/m2.What is the emissivity of the surface?
6491a) 0.2
6492308
6493b) 0.4
6494c) 0.8
6495d) 1.0
649681. In a counter flow heat exchanger, for the hot fluid the heat capacity = 2 kJ/kg K, mass flow rate = 5 kg/s, inlet temperature = 150°C, outlet temperature = 100°C. For the cold fluid, heat
6497capacity = 4 kJ/kg K, mass flow rate = 10 kg/s, inlet temperature = 20°C. Neglecting heat transfer to the surroundings, the outlet temperature of the cold fluid in °C is:
6498a) 7.5
6499b) 32.5
6500c) 45.5
6501d) 70.0
650282. In a condenser, water enters at 30°C and flows at the rate 1500 kg/hr. The condensing steam is at a temperature of 120°C and cooling water leaves the condenser at 80°C. Specific heat
6503of water is 4.187 kJ/kg K. If the overall heat transfer coefficient is 2000 W/m2K, then heat transfer area is:
6504a) 0.707 m2
6505b) 7.07 m2
6506c) 70.7 m2
6507d) 141.4 m2
650883. The logarithmic mean temperature difference (LMTD) of a counterflow heat exchanger is 20°C. The cold fluid enters at 20°C and the hot fluid enters at 100°C. Mass fl0w rate of the cold
6509fluid is twice that of the hot fluid. Specific heat at constant pressure of the hot fluid is twice that of the cold fluid. The exit temperature of the cold fluid is
6510a) 40°C
6511309
6512b) 60°C
6513c) 80°C
6514d) can not be determined
651584. In a counter flow heat exchanger, hot fluid enters at 60°C and cold fluid leaves at 30°C. Mass flow rate of the hot fluid is 1 kg/s and that of the cold fluid is 2 kg/s. Specific heat of the hot
6516fluid is 10 kJ/kgK and that of the cold fluid is 5 kJ/kgK. The Log Mean Temperature Difference (LMTD) for the heat exchanger in °C is:
6517a) 15
6518b) 30
6519c) 35
6520d) 45
652185. For the same inlet and outlet temperatures of hot and cold fluids, the Log Mean Temperature Difference (LMTD) is:
6522a) Greater for parallel flow heat exchanger than for counter flow heat
6523exchanger.
6524b) Greater for counter flow heat exchanger than for parallel flow heat
6525exchanger.
6526c) Same for both parallel and counter flow heat exchangers.
6527d) Dependent on the properties of the fluids.
652886. Hot oil is cooled from 80 to 50°C in an oil cooler which uses air as the coolant. The air temperature rises from 30 to 40°C. The designer uses a LMTD value of 26°C. The type of heat exchanger is:
6529a) Parallel flow
6530b) Double pipe
6531c) Counter flow
6532310
6533d) Cross flow
653487. Air can be best heated by steam in a heat exchanger of
6535a) Plate type
6536b) Double pipe type with fins on
6537steam side
6538c) Double pipe type with fins on air side
6539d) Shell and tube type
654088. Which one of the following heat exchangers gives parallel straight line pattern of temperature distribution for both cold and hot fluid?
6541a) Parallel-flow with unequal heat capacities
6542b) Counter-flow with equal heat capacities
6543c) Parallel-flow with equal heat capacities
6544d) Counter-flow with unequal heat capacities
654589. For a balanced counter-flow heat exchanger, the temperature profiles of the two fluids are:
6546a) Parallel and non-linear
6547b) Parallel and linear
6548c) Linear but non-parallel
6549d) Divergent from one another
655090. Consider the following statements:
6551The flow configuration in a heat exchanger, whether counterflow or otherwise, will NOT matter if:
65521. A liquid is evaporating
65532. A vapour is condensing
6554311
65553. Mass flow rate of one of the fluids is far greater
6556Of these statements:
6557a) 1 and 2 are correct
6558b) 1 and 3 are correct
6559c) 2 and 3 are correct
6560d) 1, 2 and 3 are correct
656191. Consider the following statements:
6562In a shell and tube heat exchanger, baffles are provided on the shell side to:
65631. Prevent the stagnation of shell side fluid
65642. Improve heat transfer
65653. Provide support for tubes
6566Select the correct answer using the codes given below:
6567a) 1, 2, 3 and 4
6568b) 1, 2 and 3
6569c) 1 and 2
6570d) 2 and 3
657192. In a heat exchanger, the hot liquid enters with a temperature of 180 ºC and leaves at 160 ºC. The cooling fluid enters at 30 ºC and leaves at 110 ºC. The capacity ratio of the heat exchanger is:
6572a) 0.25
6573b) 0.4
6574c) 0.5
6575d) 0.55
657693. Assertion (A): It is not possible to determine LMTD in a counter flow heat exchanger with equal heat capacity rates of hot and cold fluids.
6577312
6578Reason (R): Because the temperature difference is invariant along the length of the heat exchanger.
6579a) Both A and R are individually true and R is the correct explanation of A
6580b) Both A and R are individually true but R is not the correct explanation of A
6581c) A is true but R is false
6582d) A is false but R is true
658394. Given the following data,
6584Inside heat transfer coefficient = 25 W/m2K, Outside heat transfer coefficient = 25 W/m2K, Thermal conductivity of bricks (15 cm thick) = 0.15 W/mK,
6585The overall heat transfer coefficient (in W/m2K) will be closer to the
6586a) Inverse of heat transfer coefficient
6587b) Heat transfer coefficient
6588c) Thermal conductivity of bricks
6589d) Heat transfer coefficient based on the thermal conductivity of the bricks
6590alone
659195. In a heat exchanger with one fluid evaporating or condensing the surface area required is least in
6592a) Parallel flow
6593b) Counter flow
6594c) Cross flow
6595d) Same in all above
659696. After expansion from a gas turbine, the hot exhaust gases are used to heat the compressed air from a compressor with the help of a cross flow compact heat exchanger of 0.8
6597effectiveness. What is the number of transfer units of the heat exchanger?
6598a) 2
6599313
6600b) 4
6601c) 8
6602d) 16
660397. In a counter flow heat exchanger, the product of specific heat and mass flow rate is same for the hot and cold fluids. If NTU is equal to 0.5, then the effectiveness of the heat exchanger is:
6604a) 1.0
6605b) 0.5
6606c) 0.33
6607d) 0.2
660898. ε -NTU method is particularly useful in thermal design of heat exchangers when
6609a) The outlet temperature of the fluid streams is not known as a priori
6610b) Outlet temperature of the fluid streams is known as a priori
6611c) The outlet temperature of the hot fluid streams is known but that of the cold
6612fluid streams is not known as a priori
6613d) Inlet temperatures of the fluid streams are known as a priori
661499. A cross-flow type air-heater has an area of 50 m2. The overall heat transfer coefficient is 100 W/m2K and heat capacity of both hot and cold stream is 1000 W/K. The value of NTU is:
6615a) 1000
6616b) 500
6617c) 5
6618d) 0.2
6619100. A counter flow shell - and - tube exchanger is used to heat water with hot exhaust gases. The water (Cp = 4180 J/kg°C) flows at a rate of 2 kg/s while the exhaust gas (1030 J/kg°C)
6620314
6621flows at the rate of 5.25 kg/s. If the heat transfer surface area is 32.5 m2 and the overall heat transfer coefficient is 200 W/m2°C, what is the NTU for the heat exchanger?
6622a) 1.2
6623b) 2.4
6624c) 4,5
6625d) 8.6
6626ADDITIONAL QUESTION
66271. Which of the following statement is wrong?
6628a) The heat transfer in liquid and gases takes place according to convection.
6629b) The amount of heat flow through a body is dependent upon the material of the body.
6630c) The thermal conductivity of solid metals increases with rise in temperature,
6631d) Logarithmic mean temperature difference is not equal to the arithmetic mean temperature difference.
66322. Logarithmic mean temperature difference is not equal to the arithmetic mean temperature difference.
6633a) Reynold's number
6634b) Grashoff's number
6635c) Reynold's number, Grashoff's number
6636d) Prandtl number, Grashoff's number
66373. In a refrigerating machine, heat rejected is __________ heat absorbed.
6638a) equal to
6639b) less than
6640c) greater than
6641315
6642d) none of the options
66434. Thermal diffusivity is a
6644a) function of temperature
6645b) physical property of a substance
6646c) dimensionless parameter
6647d) all of these
66485. The total radiation from a black body per second per unit area is __________ fourth power of the absolute temperature. This statement is known as Stefan-Boltzmann law.
6649a) equal to
6650b) directly proportional to
6651c) inversely proportional to
6652d) none of these answers
66536. The amount of radiation mainly depends upon the
6654a) nature of the body
6655b) temperature of the body
6656c) type of surface of the body
6657d) all of these
66587. The highest thermal diffusivity is of
6659a) iron
6660b) lead
6661c) concrete
6662d) wood
6663316
66648. The heat transfer takes place according to
6665a) Zeroth law of thermodynamics
6666b) First law of thermodynamics
6667c) Second law of thermodynamics
6668d) Kirchhoff's law
66699. Thermal conductivity of water __________ with rise in temperature.
6670a) remains same
6671b) decreases
6672c) increases
6673d) may increase or decrease depending upon temperature
667410. The thickness of thermal and hydrodynamic boundary layer is equal if Prandtl number is
6675a) equal to one
6676b) greater than one
6677c) less than one
6678d) equal to Nusselt number
667911. A perfect black body is one which
6680a) is black in colour
6681b) absorbs heat radiations of all wave lengths falling on it
6682c) reflects all the heat radiations
6683d) transmits the heat radiations
668412. The critical radius is the insulation radius at which the resistance to heat flow is
6685a) maximum
6686b) minimum
6687317
6688c) zero
6689d) none of these
669013. Upto the critical radius of insulation,
6691a) Added insulation will increase heat loss
6692b) Added insulation will decrease heat loss
6693c) Convective heat loss will be less than conductive heat loss
6694d) Heat flux will decrease
669514. Unit of thermal diffusivity is
6696a) m²/hr
6697b) m²/hr °C
6698c) kcal/m² hr
6699d) kcal/m. hr °C
670015. The rate of energy transferred by convection to that by conduction is called
6701a) Stanton number
6702b) Nusselt number
6703c) Biot number
6704d) Peclet number
670516. Thermal conductivity of wood depends on
6706a) Moisture
6707b) Density
6708c) Temperature
6709d) All the answers given in the options.
6710318
671117. A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is
6712a) 20°C
6713b) 40°C
6714c) 60°C
6715d) 66.7°C
671618. LMTD in case of counter flow heat exchanger as compared to parallel flow heat exchanger is
6717a) Higher
6718b) Lower
6719c) same
6720d) Depends on the area of heat exchanger
672119. In heat exchangers, degree of approach is defined as the difference between temperatures of
6722a) Cold water inlet and outlet
6723b) Hot medium inlet and outlet
6724c) Hot medium outlet and cold water inlet
6725d) Hot medium outlet and cold water outlet
672620. In a shell and tube heat exchanger, baffles are provided on the shell side to
6727a) Improve heat transfer
6728b) Provide support for tubes
6729c) Prevent stagnation of shell side fluid
6730d) All of the options given
6731319
673221. Fourier's law of heat conduction gives the heat flow for
6733a) Irregular surfaces
6734b) Nonuniform temperature surfaces
6735c) One dimensional cases only
6736d) Two dimensional cases only
673722. The value of Prandtl number for air is about
6738a) 0.1
6739b) 0.3
6740c) 0.7
6741d) 1.7
674223. The product of Reynolds number and Prandtl number is known as
6743a) Stanton number
6744b) Biot number
6745c) Peclet number
6746d) Grashoff number
674724. An electric cable of aluminium conductor (k = 240 W/mK) is to be insulated with rubber (k = 0.15 W/mK). The cable is to be located in air (h = 6 W/m²). The critical thickness of insulation will be
6748a) 25 mm
6749b) 40 mm
6750c) 160 mm
6751d) 800 mm
675225. Stefan Boltzmann law is applicable for heat transfer by
6753a) Conduction
6754320
6755b) Convection
6756c) Radiation
6757d) Conduction and radiation combined
675826. The thermal diffusivities for gases are generally
6759a) More than those for liquids
6760b) Less than those for liquids
6761c) More than those for solids
6762d) Dependent on the viscosity
676327. The process of heat transfer from one particle of the body to another is called conduction, when the particles of the body
6764a) Move actually
6765b) Do not move actually
6766c) Affect the intervening medium
6767d) Does not affect the intervening medium
676828. The total emissivity power is .defined as the total amount of radiation emitted by a black body per unit
6769a) Temperature
6770b) Thickness
6771c) Area
6772d) Time
677329. The ratio of the energy absorbed by the body to total energy falling on it is called
6774a) Absorptive power
6775b) Emissive power
6776c) Absorptivity
6777321
6778d) Emissivity
677930. 40% of incident radiant energy on the surface of a thermally transparent body is reflected back. If the transmissivity of the body be 0.15, then the emissivity of surface is
6780a) 0.45
6781b) 0.55
6782c) 0.40
6783d) 0.75
678431. The amount of radiation mainly depends on
6785a) Nature of body
6786b) Temperature of body
6787c) Type of surface of body
6788d) All the options given
678932. Depending on the radiating properties, a body will be opaque when
6790a) P = 0, x = 0 and a = 1
6791b) P=1, x = 0 and a = 0
6792c) P = 0, x = 1 and a = 0
6793d) X = 0, a + p = 1
679433. The emissive power of a body depends upon its
6795a) Temperature
6796b) Wave length
6797c) Physical nature
6798d) All of the given options
6799322
680034. Absorptivity of a body will be equal to its emissivity
6801a) At all temperatures
6802b) At one particular temperature
6803c) When system is under thermal equilibrium
6804d) At critical temperature
680535. Two plates spaced 150 mm apart are maintained at 1000°C and 70°C. The heat transfer will take place mainly by
6806a) Convection
6807b) Radiation
6808c) Forced convection
6809d) Free convection
681036. In regenerator type heat exchanger, heat transfer takes place by
6811a) Direct mixing of hot and cold fluids
6812b) A complete separation between hot and cold fluids
6813c) Flow of hot and cold fluids alternately over a surface
6814d) Generation of heat again and again
681537. A perfect black body is one which
6816a) Is black in colour
6817b) Reflects all heat
6818c) Transmits all heat radiations
6819d) Absorbs heat radiations of all wave lengths falling on it
682038. Thermal conductivity of non-metallic amorphous solids with decrease in temperature
6821323
6822a) Increases
6823b) Decreases
6824c) Remain constant
6825d) May increase or decrease depending on temperature
682639. In free convection heat transfer transition from laminar to turbulent flow is governed by the critical value of the
6827a) Reynold's number
6828b) Grashoff's number
6829c) Reynold's number, Grashoff's number
6830d) Prandtl number, Grashoff's number
683140. Which of the following statement is wrong?
6832a) The heat transfer in liquid and gases takes place according to convection
6833b) The amount of heat flow through a body is dependent upon the material of the body
6834c) The thermal conductivity of solid metals increases with rise in temperature
6835d) Logarithmic mean temperature difference is not equal to the arithmetic mean temperature difference
6836Industrial Engineering and Management
68371. In computer aided process planniing determination of process sequence for manufacture of any part design without predefined standard plans is known as
6838a) Variant type process planning
6839b) Reteival type process planning
6840c) Generative type process planning
6841d) Group technology based process planning
68422. Aline balancing problem is solved inthe context of
6843324
6844a) Process layout
6845b) Product layout
6846c) Fixed position layout
6847d) Production scheduling
68483. Material Requirements Planning DOES NOT incude
6849a) Material price
6850b) Bill of material
6851c) Inventory level
6852d) Production Schedule
68534. As per the principles of motion economy which one of the following is NOT a PIVOT for a classified movement of a human body
6854a) Knee
6855b) Wrist
6856c) Torso
6857d) Elbow
68585. Which one of the following is NOT in the scope of Enterprise Resource Planning (ERP) system?
6859a) General ledger entries
6860b) Materials management system
6861c) Order management system
6862d) Employee promotion policy
68636. In a flexible manufacturing sytems AGVs move at a speed of 50 m/min, cover an average distance of 150 m to deleiver and 100 m for return. If the time required to pick-up and drop is 30 seconds each, neglecting idle times, the number of AGVs required to meet the demand of 50 deliveries per hour is
6864325
6865a) 7
6866b) 6
6867c) 5
6868d) 8
68697. A manufacturing line requires 7.2 minutes to make a product. The line has six work-stations.Total production required is 300 products in 7.5 hours. At steady state, the line efficiency is
6870a) 75%
6871b) 80%
6872c) 83%
6873d) 84%
68748. A single facility is to be located to meet the demand at coordinates (1,2), (2,3), (3,5), and (4,1). the demand at these points is 700, 100, 300, and 500 respectively. Using the rectilinear distance and weighted distance minimization criterion, the facility should be located
6875a) Anywhere on the line joining points (2,2) and (3,2)
6876b) at the point (2,3)
6877c) Anywhere on the line joining points (2,3) and (3,3)
6878d) at the point (3,3)
68799. In a time study experiment, the observed time is 15 minutes, operator rating is 90%, personal need allowance is 4%, fatigue allowance is 3%, contingency allowance for work is 3%, contingency allowance for delay is 2%. The total work content in minutes is
6880a) 15.34
6881b) 14
6882c) 16
6883d) 13.5
6884326
688510. For a canteen, the actual demand for disposable cup was 500 units in January, 600 units in February. The forecast for the month of January was 400 units. the forecast for the month of March considering smoothing coefficient as 0.75 is
6886a) 568.75
6887b) 571
6888c) 567
6889d) 555
689011. Annual demand of a product is 50000 units, and the ordering cost is Rs. 7000 per order. Considering the basic EOQ model, the economic order quantity is 10000 units. The annual inventory holding cost is
6891a) Rs.3.8/unit/year
6892b) Rs.3.6/unit/year
6893c) Rs.3.5/unit/year
6894d) Rs.3.9/unit/year
689512. Number of units sold in January, February, March, April and May are 10, 11, 16, 19, and 25 respectively. Regarding forecast for the month of June, which of the following statements is TRUE?
6896a) Moving average will forecast a higher valuecompared to regression.
6897b) Higher the value of order N, the greater will be the forecast value by moving average.
6898c) Exponential smoothing will forecast a higher valuecompared to regression.
6899d) Regression will forecast a higher valuecompared to moving average.
690013. Amanufacturer has the following data regarding a product. Fixed cost Rs.50000; Variable cost Rs.200; Selling price per unit Rs.300; Production capacity 1500 units per month; If the production is carried out at 80% of the rated capacity, then the monthly profit is
6901a) 65000
6902b) 70000
6903c) 66000
6904327
6905d) 71000
690614. The annual demand for an item is 10000 units. The unit cost is Rs.100 and the carrying cost is 14.4% of the unit cost per annum. The cost of one procurement is Rs.2000. The time between two consecutive orders to meet the above demand is
6907a) 1.41 months
6908b) 1.53 months
6909c) 1.6 months
6910d) 1.7 months
691115. The demand for two wheeler was 900 units and 1030 units in april 2015 and May 2015 respectively. The forecast for the month April was 850, considering smoothing constant of 0.6, forecast for the month of June 2015 is
6912a) 850 units
6913b) 927 units
6914c) 965 units
6915d) 970 units
6916328
6917Industrial Engineering and Management
69181. Qualitative forecasting methods
6919a) are made objectively by the forecaster
6920b) are made subjectively by the forecaster
6921c) are made using existing data sources
6922d) are based on mathematical models
69232. Which forecasting method seeks to develop a consensus among a group of experts?
6924a) Market research
6925b) Executive opinion
6926c) Delphi method
6927d) Naïve method
69283. Which forecasting method is particular good for predicting technological changes and scientific advances?
6929a) Market research
6930b) Executive opinion
6931c) Delphi method
6932d) Naïve approach
69334. Which forecasting method assumes that next period’s forecast is equal to this period’s actual value?
6934a) Simple mean
6935b) exponential smoothing
6936c) Basic
6937d) Naïve
6938329
69395. Suppose that you are using the naïve forecasting method with trend to forecast sales. If sales have been declining by 20% per week, and this week’s sales amounted to $200, what would your forecast be for next week?
6940a) $200
6941b) $ 40
6942c) $240
6943d) $160
69446. Suppose that you are using the simple mean to make a forecast. This period’s forecast was equal to 100 units, and it was based on 6 periods of demand. This period’s actual demand was 86 units. What is your forecast for next period?
6945a) 98
6946b) 100
6947c) 93
6948d) 86
69497. Suppose that you are using the four-period simple moving average method to forecast sales, and sales have been decreasing by 10% every period. How will your forecasts perform?
6950a) Forecasts will be lower than actual.
6951b) Forecasts will be higher than actual.
6952c) Forecasts will equal actual.
6953d) Forecasts will be decreasing by 2.5% every period.
69548. In exponential smoothing, what values can the smoothing constant have?
6955a) [-1, 1]
6956b) [1, 100]
6957c) [0, -1]
6958d) [0, 1]
6959330
69609. In linear regression, what are we trying to forecast?
6961a) Beta parameter
6962b) Dependent variable
6963c) Independent variable
6964d) Y-intercept of the line
696510. What does the linear regression line do?
6966a) Minimizes sum of errors
6967b) Minimizes product of squared errors
6968c) Minimizes sum of squared errors
6969d) Minimizes product of errors
697011. What value of the correlation coefficient implies that there is a perfect positive linear relationship between the two variables of a linear regression model?
6971a) 100
6972b) 0
6973c) 0.5
6974d) 1
697512. In a linear regression analysis, coefficient of determination value 0.984 implies what?
6976a) 98.4% of the variability of the independent variable is explained by the dependent variable
6977b) 98.4% of the variability of the dependent variable is explained by the independent variable
6978c) 1.6% of the variability of the independent variable is explained by the dependent variable
6979d) 1.6% of the variability of the dependent variable is explained by the independent variable
698013. What value of the correlation coefficient implies that there is no relationship between the two variables of a linear regression model?
6981331
6982a) 1
6983b) 0
6984c) 0.5
6985d) 1
698614. What is the statistic that measures the direction and strength of the linear relationship between two variables?
6987a) Coefficient of determination
6988b) Coefficient of variation
6989c) Variance
6990d) Correlation coefficient
699115. Which of the following values of the correlation coefficient implies that the value of the dependent variable decreases as the value of the independent variable increases?
6992a) -0.2
6993b) 0
6994c) 0.2
6995d) 1
699616. The following correlation coefficient values come from five different linear regression models. Which model “fits” the data the best?
6997a) 0.99
6998b) 0.5
6999c) -1
7000d) 0
700117. Suppose that Sally’s company uses exponential smoothing to make forecasts. Further suppose that last period’s demand forecast was for 20,000 units, and last period’s actual
7002332
7003demand was 21,000 units. Sally’s company uses a smoothing constant (α) equal to 40%. What should be the forecast for this period?
7004a) 20,000
7005b) 21,000
7006c) 20,600
7007d) 20,400
700818. Suppose that you are using the four-period simple moving average method to forecast sales, and sales have been increasing by 20% every period. How will your forecasts perform?
7009a) Forecasts will be lower than actual.
7010b) Forecasts will be higher than actual.
7011c) Forecasts will equal actual.
7012d) Forecasts will be increasing by 5.0% every period.
701319. Suppose that you are using the four-period simple moving average method to forecast sales, and sales have been increasing by 40% every period. How will your forecasts perform?
7014a) Forecasts will be decreasing by 53.76% every period.
7015b) Forecasts will be higher than actual.
7016c) Forecasts will equal actual.
7017d) Forecasts will be increasing by 10.0% every period.
701820. Which of the following is has positive price elasticity?
7019a) Products that do not obey the law of demand
7020b) Products that obey the law of demand
7021c) Substitute goods
7022d) Essential goods
7023333
702421. The coefficient of determination for an independent variable in a linear regression model is 0.81. The correlation coefficient is
7025a) 0.8175
7026b) 0.6561
7027c) 0.9
7028d) 0.6
702922. Economics indicates that the world economy fluctuates over the long term. What type of data pattern would this be?
7030a) cycles
7031b) linear
7032c) seasonal
7033d) level
703423. Price elasticity is equal to 1 for a product, which of the following is true?
7035a) Total revenue will not change
7036b) Total revenue will decrease
7037c) Total revenue will increase
7038d) total revenue will increse by 20%
703924. The variation in the actual sales of a product can be described using a single independent variable if the
7040a) Correlation coefficient is close to 1
7041b) Coefficient of determination is exactly 1
7042c) the mean of the dependent variable is more than 200
7043d) the trend and seasonal factors are occasionally present
7044334
704525. A hospital wants to improve its existing layout. Which algorithm would you suggest
7046a) ALDEP
7047b) CRAFT
7048c) CORELAP
7049d) Rank order clustering
705026. CRAFT considers exchange of locations for those departments which
7051a) Have the same area
7052b) Have a common border
7053c) Departments in the centre
7054d) Have same costs per unit distance
705527. While using the ALDEP algorithm for layout design, the algorithm starts with the randomly selected department to be positioned in the top left corner of the layout. The adjacent department is selected based on
7056a) Closeness rating
7057b) Placement rating
7058c) The size of the department and TCR value
7059d) Minimum department preference (MDP)
706028. Ship building and construction of dams are the typical examples of
7061a) Fixed position layout
7062b) Functional layout
7063c) Product layout
7064d) Project type layout
706529. Which of the following is a two handed process chart
7066a) SIMO
7067335
7068b) Flow process chart (Material)
7069c) Operation process chart
7070d) Flow process chart(Operator type)
707130. Repetitive strain injuries can be reduced by
7072a) Time study
7073b) Method study
7074c) Ergonomic design of work place
7075d) Work sampling
707631. The challenge in process layouts is to arrange resources to maximize _____ and minimize ____
7077a) movement, effectiveness
7078b) effectiveness, efficiency
7079c) efficiency, waste of movement
7080d) efficiency, effectiveness
708132. A company with a pure continuous processing system is most likely to use which layout type?
7082a) inverted
7083b) hybrid
7084c) process
7085d) product
708633. Process layouts have
7087a) less automation
7088b) more automation
7089c) fewer employees
7090336
7091d) more cycle time
709234. A job shop is most likely to use which layout type?
7093a) inverted
7094b) hybrid
7095c) process
7096d) fixed position
709735. A grocery store is most like which of the following layout types?
7098a) inverted
7099b) circular
7100c) process
7101d) fixed position
710236. A company with a pure intermittent processing system is most likely to use which layout type?
7103a) Product
7104b) Process
7105c) Cellular
7106d) Fixed position
710737. A single-line cafeteria is an example of which layout type?
7108a) product
7109b) process
7110c) cellular
7111d) hybrid
7112337
711338. A car wash is an example of which layout type?
7114a) product
7115b) process
7116c) cellular
7117d) fixed position
711839. A high-volume paper mill is an example of which layout type?
7119a) process
7120b) product
7121c) hybrid
7122d) cellular
712340. Which of the following is least like a product layout?
7124a) high-volume paper mill
7125b) automobile plant
7126c) hospital
7127d) car wash
7128Industrial Engineering and Management
71291. Which company is widely considered to be the leader of just-in-time production?
7130a) Ford
7131b) Timex
7132c) Gateway
7133d) Toyota
71342. What are the two primary tools used to identify closeness measures during the layout design process?
7135338
7136a) REL chart and from-to matrix
7137b) MRP chart and from-to matrix
7138c) x-bar chart and from-to matrix
7139d) MRP chart and x-bar chart
71403. How many different layout solutions are possible with 7 departments?
7141a) 7
7142b) 720
7143c) 28
7144d) 5040
71454. How many pairs of departments you have to swap if the given layout has 5 departments
7146a) 5
7147b) 10
7148c) 15
7149d) 20
71505. What is the term for the maximum amount of time each workstation has to complete its assigned task?
7151a) output rate
7152b) task time
7153c) station time
7154d) cycle time
71556. Group technology creates groupings of products primarily based on what?
7156a) product cost
7157b) raw materials requirements
7158339
7159c) similar processing requirements
7160d) operating characteristics
71617. What technique eliminates unnecessary tasks and improves the process for completing tasks?
7162a) method study
7163b) time study
7164c) work sampling
7165d) ergonomics
71668. Method study results in
7167a) a graph of how long each step takes
7168b) an evaluation of current employees
7169c) guidance for designing jobs
7170d) a standard, detailed procedure for an operation
71719. The steps involved in a time study include all except which of the following?
7172a) Time each element, record the times, and rate the worker’s performance.
7173b) Tell the worker whose job you will be studying.
7174c) Calculate the number of cycles you must observe.
7175d) Determine the probability distribution that best fits the observed times.
717610. Typically the job chosen for the time study will be
7177a) a routine job that is labor intensive
7178b) a simple job performed by many different people
7179c) done primarily by machine
7180d) done only occasionally
7181340
718211. The formula for determining the number of observations needed depends upon all except which of the following values?
7183a) the number of standard deviations needed for the desired confidence
7184b) the maximum observed value in the sample
7185c) the standard deviation of the sample observations
7186d) the mean of the sample observations
718712. How many standard deviations is required for a 98% confidence level?
7188a) 2
7189b) 2.05
7190c) 2.17
7191d) 2.33
719213. What is the effect of an increase in the desired confidence level on the number of observations necessary in a time study?
7193a) increases
7194b) decreases
7195c) unchanged
7196d) may increase or decrease
719714. When performing a time study, the analyst converts the observed time into the time an "average" worker would require working at an acceptable pace by using which of the following?
7198a) allowance factor
7199b) mean time modulation
7200c) methods analysis
7201d) performance rating factor
7202341
720315. Which of the following values for performance rating factor would be for an above-average work pace?
7204a) 90%
7205b) 100%
7206c) 65%
7207d) 140%
720816. In a time study, personal time, fatigue, and unavoidable delays (PFD) during the typical work day are accounted for in what?
7209a) the normal time
7210b) an allowance factor
7211c) the performance rating
7212d) how the work elements are defined
721317. If OT = the mean observed time, PRF = the performance rating factor, F = the frequency of occurrence, and PFD = the percentage allowance based on time worked, what is the formula to compute the standard time?
7214a) (OT)(PRF)(F)
7215b) (OT)(PRF)(F)(1 + PFD)
7216c) (OT)(PRF)(F) / (1 – PFD)
7217d) (OT)(PRF)(F) / (1 + PFD)
721818. If OT = the mean observed time, PRF = the performance rating factor, F = the frequency of occurrence, and PFD = the percentage allowance adjustment based on job time, what is the formula to compute the standard time?
7219a) (OT)(PRF)(F)
7220b) (OT)(PRF)(F)(1 + PFD)
7221c) (OT)(PRF)(F) / (1 – PFD)
7222342
7223d) (OT)(PRF) / (F)
722419. Which of the following would not be a basic element into which a job would be split when using predetermined time data?
7225a) reach
7226b) sort
7227c) grasp
7228d) insert
722920. Which of the following is a basic difference of work sampling compared to a time study?
7230a) It does not require any observations.
7231b) It requires fewer observations to accomplish the same thing.
7232c) It is better suited for short, repetitive tasks.
7233d) It does not provide standard times.
723421. Work sampling provides
7235a) normal time
7236b) standatrd time
7237c) proportion of time a person is spending on each of the assigned tasks
7238d) allowances
723922. Cross price elasticity of demand for substitutes
7240a) positive
7241b) negative
7242c) exponential
7243d) cannot be estimated
7244343
724523. Cross price elasticity of demand for compliments
7246a) positive
7247b) negative
7248c) unity
7249d) zero
725024. which of the following will have positive price elasticity
7251a) vanity bags
7252b) budget cars
7253c) movie ticket
7254d) petrol
725525. Vebeln goods are
7256a) very costly goods
7257b) cheap goods
7258c) moderately priced goods
7259d) rare items
726026. Giffin goods are
7261a) very costly goods
7262b) cheap goods
7263c) moderately priced goods
7264d) substitutes
726527. petrol and car are
7266a) substitte goods
7267b) complement goods
7268344
7269c) essential goods
7270d) luxary goods
727128. Opening stock of raw material should be
7272a) added to the prime cost
7273b) added to the factory cost
7274c) added to the total cost
7275d) added to the administarive overhead
727629. opening stock of work in progress should be
7277a) added to the prime cost
7278b) added to the factory cost
7279c) added to the total cost
7280d) added to the cost of production
728130. Depreciation of machineries should be added to
7282a) prime cost
7283b) factory cost
7284c) cost of production
7285d) total cost
728631. Ergonomics deals with
7287a) work system design
7288b) method study
7289c) safety
7290d) time study
7291345
729232. JIT aims at
7293a) maximum inventory
7294b) single piece flow
7295c) enhancing the worker safety
7296d) minimizing the material handling
729733. KANBAN is a
7298a) push system
7299b) pull system
7300c) method study process
7301d) work sampling process
730234. The number of 1s outside the machine-part cells are called as
7303a) voids
7304b) exceptional elements
7305c) unproductive activity
7306d) non-critical activity
730735. The number of zeros inside the machine-part cells are called as
7308a) voids
7309b) exceptional elements
7310c) non critical elements
7311d) critical elements
731236.
7313In the CORELAP algorithm for layout design, the department with maximum TCR is placed in the
7314346
7315a) top left corener
7316b) top right corner
7317c) center
7318d) bottom left corner
731937. Placement rating is used in the CORELAP algorithm for
7320a) deciding the position of the first department with maximum TCR
7321b) deciding the position for the second department
7322c) deciding the position of the third department and the subsequent departments
7323d) deciding the number of iterations required
732438. Grouping efficacy of the machine-part cells is calculated using
7325a) voids
7326b) exceptional elements
7327c) voids and exceptional elements
7328d) total number of 1s in the matrix, exceptional elements and voids
732939. Total number of 1s in the machine-part incidence matrix is 40. The number of exceptional elements and voids are 5 and 4 respectively. The grouping efficacy is
7330a) 0.6534
7331b) 0.7954
7332c) 0.7132
7333d) 0.8345
733440. Total number of 1s in the machine-part incidence matrix is 100. The number of exceptional elements and voids are 15 and 13 respectively. The grouping efficacy is
7335a) 0.7522
7336b) 0.6522
7337347
7338c) 0.5522
7339d) 0.8522
734041. The Mean observed time of an activity is 90 seconds. If the rating factor is 110%, what is the normal time?
7341a) 109 seconds
7342b) 99 seconds
7343c) 103 seconds
7344d) 89 seconds
734542. The Mean observed time of an activity is 90 seconds. If the rating factor is 110%, 13% PFD allowance is given. What is the Standard time based on the time worked?
7346a) 112.79
7347b) 111.79
7348c) 114.79
7349d) 113.79
735043. The standard deviation and the mean of a time study experiment based on 10 observations are 0.010 and 0.12 respectively. How many observations are required to deicde the standard time to be within 5% of the true mean with 95% confidence (z = 1.96).
7351a) 15
7352b) 10
7353c) 23
7354d) 11
735544. For all the goods except the veblen and giffin goods, the price elacticity of demand is
7356a) negative
7357b) positive
7358348
7359c) infinity
7360d) between 2 and 3
736145. Operation process chart is for recording
7362a) two hand movements of an operator
7363b) operations and inspections
7364c) flow of material
7365d) flow of operator
7366Kinematics of Machinery
73671. The mechanism used in a shaping machine is
7368a) a closed 4-bar chain having 4 revolute pairs
7369b) a closed 6-bar chain having 6 revolute pairs
7370c) a closed 4-bar chain having 2 revolute pair and 2 sliding pairs
7371d) an inversion of the single slider-crank chain
73722. The legnths of the links of a 4-bar linkage with revolute pairs only are p, q, r and s units. Given that p < q < r < s. Which of these links should be the fixed one, for obtaining a "double crank" mechanism?
7373a) links of length p
7374b) links of length q
7375c) links of length r
7376d) links of length s
73773. The number of degrees of reedom of a planar linkage with 8 links and 9 simple revolute joint is
7378a) 1
7379b) 2
7380349
7381c) 3
7382d) 4
73834. In a four- bar linkage, S denotes the shortest link length, L is the longest link length, P and Q are the lengths of other two links. At least one of the three moving links will rotate by 360 degree if
7384a) S + L less than or equal to P + Q
7385b) S + L > to P + Q
7386c) S + P less than or equal to L + Q
7387d) S + P > to L + Q
73885. Mobility of a statically indeterminate structure is
7389a) Less than equal to -1
7390b) 0
7391c) 1
7392d) Greater than or equal to 2
73936. For a four bar linkage in toggle position, the value of mechanical advantage is?
7394a) 0
7395b) 0.5
7396c) 1
7397d) infinite
73987. A 1.5kW motor is running at 1440 rev/min. It is to be connected to a stirrer running at 36 rev/min. The gearing arrangement suitable for this application is?
7399a) differential gear
7400b) helical gear
7401c) spur gear
7402350
7403d) spur gear
74048. The cam follower generally used in automobile engines is
7405a) knife edge follower
7406b) knife edge follower
7407c) spherical faced follower
7408d) roller follower
74099. A chain consisting of four links and four joints is called ....
7410a) kinematic chain
7411b) pair
7412c) structure
7413d) redundant chain
741410. The inversion of a mechanism is
7415a) changing of a higher pair to a lower pair
7416b) turning its upside down
7417c) obtained by fixing different links in a kinematic chain
7418d) obtained by reversing the input and output motion
7419Kinematics of Machinery
74201. When particle moves with a uifrom velocity along a circular path, then the particle has
7421a) tangetial acceleration only
7422b) centreipetal acceleration only
7423c) both centreipetal acceleration and tangetial acceleration only
7424d) coriolis only
7425351
74262. The connection between the piston and cylinder in reciprocating corresponding to
7427a) completly constrained kinematic pair
7428b) incompletly constrained kinematic pair
7429c) Sucessfully constrained kinematic pair
7430d) single link
74313. which of the following are examples of force closed kinmatics pairs
74321. cam and roller mechanism
74332. Door closing mechanism
74343. slider crank mechanism
74354. Automotive clutch opearting mechansim
7436a) 1,2 and 4
7437b) 1 and 3
7438c) 2,3 and 4
7439d) 1,2,3 and 4
74404. consider the following pairs
74411. pair of gear in mesh
74422. Belt and pulley
74433. cylinder and pistonn
74444. cam and follower
7445Among these, the higher pairs are
7446a) 1 and 4
7447b) 2 and 4
7448c) 1,2 and 3
7449352
7450d) 1,2 and 4
74515. A linkage is shown below in the figure in which ABC and DEF are ternary links where as AF, BE and CD are binary links.
7452The degree of freedom of the linkage when link ABC is fixed are
7453<img src="dof.png" alt="dof.png" title="dof" width="477" height="298"></img>
7454a) 0
7455b) 1
7456c) 2
7457d) 3
74586. The centre of gravity of the coupler link in a 4-bar mechanism would
7459experience
7460a) No acceleration
7461b) only linear acceleration
7462c) Only angular acceleration
7463d) both linear and angular accelerations
74647. In order to draw the acceleration diagram, it is necessary to determine the
7465Corioli’s component of acceleration in the case of
7466a) crank and slotted lever quick return mechanism
7467b) slider-crank mechanism
7468c) four bar mechanism
7469d) pantograph
7470353
74718. In a mechanism, the fixed instataneous centres are those centres which
7472a) remain in same place for all configration of the mechanism
7473b) vary with the configuration of the mechansim
7474c) moves as the mechanism moves
7475d) fixed
74769. when a slider moves on a curved surface, their instantanous center liies
7477a) on the poin of contact
7478b) at the center of curvature
7479c) at the center of circle
7480d) at the pin joint
748110. The direction of linear velocity of any point on a link with respect to another point on the same link is
7482a) parallel to the link
7483b) perpendicular to the link joining the points
7484c) at 45 degree to the link joining the points
7485d) at 30 degree
748611. In a reciprocating engine, which of the following forms a kinematic link
7487a) cylinder and piston
7488b) piston and connecting rod
7489c) crank shaft and flywheel
7490d) flywheel and engine frame
749112. Ball and socket forms a
7492a) turning pair
7493354
7494b) rolling pair
7495c) sliding pair
7496d) spherical pair
749713. The lead screw of lathe with nut forms a
7498a) turning pair
7499b) rolling pair
7500c) screw pair
7501d) force closed pair
750214. when the element of the pair are kept in contact by the action of external forces, the pairs are said to be
7503a) lower pair
7504b) higher pair
7505c) self closed pair
7506d) force closed pair
750715. A combination of kinematic pairs, joined in such a way that the relative motion between link is completly constrained, is called as
7508a) structure
7509b) mechanism
7510c) kinematic chain
7511d) inversion
751216. The relation between number of pairs (p) forming a kinematic chain and number of links (l) is
7513a) l = 2p - 2
7514b) l = 2p - 3
7515355
7516c) l = 2p - 4
7517d) l = 2p - 5
751817. A kinematic chian is known as a mechanism when
7519a) none of the links fixed
7520b) one of the links fixed
7521c) two of the links fixed
7522d) all of the links are to be fixed
752318. which of the following is an inversion of slider crank chain?
7524a) beam engine
7525b) watt indicator
7526c) elliptical trammel
7527d) whit worth quick return motion mechanism
752819. which of the following is an inversion of double slider crank chain ?
7529a) coupling of a locomotive
7530b) pendulum pump
7531c) elliptical trammel
7532d) oscilating cylinder engine
753320. When relative motion between two element is completely or successfully constrained, the these two elements from a
7534a) mechanism
7535b) machine
7536c) kinematic pair
7537d) kinematic chain
7538356
753921. Ball bearing and roller bearing form a
7540a) turning pair
7541b) rolling pair
7542c) sliding pair
7543d) spherical pair
754422. Which one of the following is a lower pair?
7545a) ball and roller bearing
7546b) automobile steering gear
7547c) cam and follower
7548d) belt and chain drives
754923. Choose the correct statement
7550a) sliding pair has incompletely constrained motion
7551b) a pair of friction discs constitutes a lower pair
7552c) rectilinear motion of a piston is converted into rotary motion by slider crank
7553d) automobile steering gear is an example of higher pair
755424. The motion of a shaft with collars at each endin a circular hole is an example of
7555a) incompletely constrained motion
7556b) completely constrained motion
7557c) successfully constrained motion
7558d) none of the above
755925. motion of a shaft a circular hole is an example of
7560a) incompletely constrained motion
7561357
7562b) completely constrained motion
7563c) successfully constrained motion
7564d) force closed
756526. The differential mechanism of an automobile is having degree of freedom
7566a) 1
7567b) 2
7568c) 3
7569d) 4
757027. The Ackermann steering gear is the inversion of
7571a) slider crank chain
7572b) four bar chain
7573c) crossed slider crank chain
7574d) double slider crank chain
757528. Oldham's coupling and elliptic trammels are the inversion of
7576a) double slider crank chain
7577b) single slider crank chain
7578c) four bar chain
7579d) crossed slider crank chain
758029. any point on a link connecting double slider chain will trace a
7581a) straight line
7582b) circle
7583c) ellipse
7584d) parabola
7585358
758630. a mechanism is assemblage of
7587a) two links
7588b) three linnks
7589c) four links or more than four links
7590d) five link
759131. a sliding crank chain consists of following number of turning and sliding pairs
7592a) 1, 3
7593b) 2,2
7594c) 3,1
7595d) 4,1
759632. The tendency of body to resist change from rest or motion is known as
7597a) resisting torque
7598b) friction
7599c) inertia
7600d) resisting force
760133. Typewriter constitutes
7602a) Machine
7603b) structure
7604c) mechansim
7605d) pair
760634. A cam mechanism imparts following motion
7607a) rotating
7608359
7609b) ocsillating
7610c) reciprocating
7611d) not any of the above
761235. open pairs are thosee which have
7613a) point or line contact
7614b) surface contact
7615c) elements of pair are not held together mechanically
7616d) two elements permits relative motion
761736. For a kinematic chain to be considered as mechanism
7618a) two links should be fixed
7619b) one links should be fixed
7620c) none of the above
7621d) there is no such criterion
762237. In simplest form, a cam mechanism consists of following number of links
7623a) 1
7624b) 2
7625c) 3
7626d) 4
762738. In SHM motion, acceleration is proportional to
7628a) velocity
7629b) displacement
7630c) rate of change of velocity
7631d) stroke
7632360
763339. For a SHM motion of the follower, a cosine curve represents
7634a) displacement
7635b) velocity
7636c) acceleration
7637d) jerk
763840. The number of links and instantaneous centers in a reciprocating engine mechanism are
7639a) 4,6
7640b) 4,5
7641c) 5,4
7642d) 6,4
764341. According to kennndys theorem, if three bodies have plane motion, their instantaneous centers lie on
7644a) triangle
7645b) a point
7646c) two lines
7647d) a straight line
764842. Angular acceleration of a link can be determined by dividing the
7649a) centrepetal component of accelration with length of link
7650b) tangential component of accelration with length of link
7651c) resultant with link length
7652d) velocity
765343. Klien's construction is useful to determine
7654361
7655a) velocity of various parts
7656b) acceleration of various parts
7657c) displacement of varoius parts
7658d) angular accelearion of various parts
765944. A circle passing through the pitch point with its center at the center of cam axis is known as
7660a) pitch circle
7661b) base circle
7662c) prime circle
7663d) cam circle
766445. The two parallel and coplanar shafts are connected by gears having teeth parallel to the axis of the shaft. This arrangement is called
7665a) Spur gearing
7666b) helical gearing
7667c) Bevel Gear
7668d) Spiral gear
766946. The size of the gear is usually give by
7670a) Addendum circle
7671b) Dedendum
7672c) pitch circle
7673d) clearance circle
767447. The radial distance of tooth from the pitch circle to the top of the tooth is called
7675a) Dedendum
7676b) addendum
7677362
7678c) clearance
7679d) working depth
768048. The product of diametral pitch and circular pitch is equal to
7681a) 1
7682b) 1/Ï€
7683c) π
7684d) 2Ï€
768549. Involute profile is preferred to cycloid because
7686a) The pitch is easy to cut
7687b) Only one curve is required to cut
7688c) all of above
7689d) none of the above
769050. The contact ratio for gear is
7691a) 0
7692b) 1
7693c) more than 1
7694d) 1.5
769551. cam size depends on
7696a) base circle
7697b) pitch circle
7698c) prime circle
7699d) outer circle
7700363
770152. The maximum value of pressure angle in case of cam is kept as
7702a) 10 degree
7703b) 14 degree
7704c) 20 degree
7705d) 30 degree
770653. For the same lift and same angle of ascent, a smaller base circle will give
7707a) small value of pressure angle
7708b) large value of pressure angle
7709c) there is no such relation
7710d) something else
771154. A rigid body possesses_____degrees of freedom.
7712a) 1
7713b) 2
7714c) 4
7715d) 6
771655. Transmission angle is the angle between
7717a) Input link and coupler
7718b) Input link and fixed link
7719c) Output link and coupler
7720d) Output link and fixed link
772156. ________ is an inversion of Double slider crank chain.
7722a) Coupling rod of a locomotive
7723b) Scotch yoke mechanism
7724364
7725c) Hand pump
7726d) Reciprocating engine
772757. The Kutzbach criterion for determining the number of degrees of freedom (n) is (where l = number of links, j = number of joints and h = number of higher pairs)
7728a) n = 3(l-1)-2j-h
7729b) n = 2(l-1)-2j-h
7730c) n = 3(l-1)-3j-h
7731d) n = 2(l-1)-3j-h
773258. A fixed gear having 200 teeth is in mesh with another gear having 50 teeth. The two gears are connected by an arm. The number of turns made by the smaller gear for one revolution of arm about the centre of bigger gear is
7733a) 2
7734b) 4
7735c) 3
7736d) 5
773759. Which gear is used for connecting two coplanar and intersecting shafts?
7738a) Spur gear
7739b) Helical gear
7740c) Bevel gear
7741d) worm gear
774260. Module of a gear is
7743a) D/T
7744b) T/D
7745c) 2D/T
7746365
7747d) 2T/D
774861. Length of arc of contact is given by
7749a) Arc of approach - Arc of recess
7750b) Arc of approach + Arc of recess
7751c) Arc of approach / Arc of recess
7752d) Arc of approach x Arc of recess
775362. The type of gears used to connect two non parallel and non intersecting shafts is
7754a) Spur gear
7755b) Helical gear
7756c) Bevel gear
7757d) Spiral gear
775863. In which of the following type of gear train the first gear and the last gear are co-axial.
7759a) Simple gear train
7760b) Compound gear train
7761c) Reverted gear train
7762d) epicyclic
776364. Which gear train is used for higher velocity ratios in a small space?
7764a) Simple gear train
7765b) Compound gear train
7766c) Reverted gear train
7767d) Epicyclic gear train
776865. Which type of gear train is used in clock mechanism to join hour hand and minute hand?
7769366
7770a) Simple gear train
7771b) Compound gear train
7772c) Reverted gear train
7773d) Epicyclic gear train
777466. Which type of gearing is used in steering system of an automobile?
7775a) Rack and pinion
7776b) Worm and wheel
7777c) Spiral gears
7778d) None of the above
777967. Which one of the following is an exact straight line mechanism using lower pairs?
7780a) Watt’s mechanism
7781b) Grasshopper mechanism
7782c) Robert’s mechanism
7783d) Paucellier’s mechanism
778468. Consider the following mechanisms:
77851.Oscillating cylinder engine mechanism
77862.Toggle mechanism
77873. Radial cylinder engine mechanism
77884. Quick return mechanism
7789Which of the above are inversions of slider crank mechanism?
7790a) 1, 2 and 4
7791b) 2, 3 and 4
7792c) 1, 2 and 3
7793367
7794d) 1, 3 and 4
779569. Which of the following is open pair
7796a) journal bearing
7797b) Ball and socket joint
7798c) leave screw and nut
7799d) all of the above
780070. which of the gear train is used for higher velocity ratios in small space?
7801a) simple gear train
7802b) compound gear train
7803c) reverted gear train
7804d) epicyiclic gear train
780571. The component of acceleration,parallel to the veloity of the particle, at the given instant is called
7806a) radial component
7807b) tangential componnent
7808c) coriolis component
7809d) resultant
781072. The radial distance of a tooth from pitch circle to the bottom of the tooth is called
7811a) dedundum
7812b) addendum
7813c) clearance
7814d) working depth
7815368
781673. The module is reciprocal of
7817a) diametral pitch
7818b) circular pitch
7819c) pitch diameter
7820d) pressure angle
782174. Mitre gears are used for
7822a) great speed reduction
7823b) equal speed
7824c) minimum axial thrust
7825d) minimum backlash
782675. The condtion for correct gearing is
7827a) pitch line velocities of teeth be same
7828b) radius of curavture of two profile be same
7829c) common normal to the pitch surface cuts the line of centres at a fixed point
7830d) pitch line velocities of teeth different
783176. Involute profile is prefered to cycloid because
7832a) the profile is easy to cut
7833b) only one curve is required to cut
7834c) the rack has straight line profile and hence can be cut accurately
7835d) smoother operation
783677. Interfernece can be avoided in involute gears with 20 degree pressure angle by
7837a) cutting involute correctly
7838b) using as small umber of teeth as possible
7839369
7840c) using more than 20 teeth
7841d) using more than 8 teeht
784278. In simple gear train, if the number of idle gears is odd, then the motion of driven gear will
7843a) be same as that of driving gear
7844b) be opposite as that of driving gear
7845c) depend upon the number of teeth on the driving gear
7846d) none of the above
784779. The train value of gear is
7848a) equal to velocity ration of a gear train
7849b) reciprocal of velocityy ratio of a gear train
7850c) always greater that unity
7851d) always less than unity
785280. In a gear train, when the axes of the shafts, over which the gears are mounted, move relative to a fixed axis is called
7853a) epicyclic gear train
7854b) reverted gear train
7855c) compound gear train
7856d) simple gear train
785781. A differential gear in an automobile is a
7858a) simple gear train
7859b) epicyclic
7860c) compound gear train
7861d) compound gear
7862370
786382. A differential gear in automobile is used to
7864a) reduce the speed
7865b) assist in changing in speed
7866c) provide jerk free movement of vehicle
7867d) help in turning
786883. The angle between the direction of the follower motion and a normal to the pitch curve is called
7869a) pitch angle
7870b) prime angle
7871c) base angle
7872d) pressure angle
787384. The cam follower generally used in automobile
7874a) kife edge follower
7875b) flat faced folower
7876c) spherical faced follwer
7877d) roller follwer
787885. The cam follower extensively used in air craft engines is
7879a) knife edge follower
7880b) flat faced follower
7881c) spherical faced follower
7882d) roller follwer
788386. In a radial cam, the follower moves
7884371
7885a) in a direction perpendicular to the cam axis
7886b) in a direction parallel to cam axis
7887c) in any direction irrespective of the cam axis
7888d) along the cam axis
788987. A radial follower is one
7890a) That reciprocates in the guides
7891b) that ocillates
7892c) in which the follower translates along an axis passing throgh the cam centre of rotation
7893d) translates
789488. offset is provided to a cam follower mechanism to
7895a) minimise the side thrust
7896b) accelerate
7897c) avoid jerk
7898d) reduced the noise
789989. For a low and moderate speed engines, the cam follower should move with
7900a) uniform velocity
7901b) simple harmonic motion
7902c) uniform acceleration and retardation
7903d) cycloidal motion
790490. For high speed engines, the cam and follwer should move with
7905a) uniform velocity
7906b) simple harmonic motion
7907c) uniform acceleration and retardation
7908372
7909d) cycloidal motion
791091. which of the following displacement diagrams should be chosen for better dynamic perforamance of cam follower motion
7911a) simple harmonic motion
7912b) parabolic motion
7913c) cycloidal motion
7914d) tangent
791592. A combination of kinematic pairs, joined in such a way that the relaitve motion between the linkage is compltly constrained is called as
7916a) structure
7917b) mechanism
7918c) kinematic chain
7919d) inversion
792093. The mechanism forms a structure, when the number of degree of freedom is equal to
7921a) 0
7922b) 1
7923c) 2
7924d) -1
792594. In a four bar chain or quadric cycle
7926a) each of the four pairs is turning pair
7927b) one is a turning pair and three sliding pairs
7928c) three are turning pairs and one is sliding pair
7929d) all are sliding pairs
7930373
793195. The total number of instantaneous centers for a mechanism consiting of n links are
7932a) n/2
7933b) n
7934c) (n-1)/2
7935d) [n(n-1)]/2
793696. The instantaneous centers which vary with the configuration of the mechanism are called
7937a) permanet instantaneous centres
7938b) fixed instantaneous centres
7939c) neither fixed norpermanet instantaneous centres
7940d) flexible instantaneous centres
794197. The two parallel and coplanar shafts are connected by gears having parallel teeth to the axis of the shaft. the arrangement is called
7942a) spur gearing
7943b) helical gearing
7944c) bevel gearing
7945d) spiral gearing
794698. An imaginary circle which by pure rolling action gives the same motion as the actual gear is called
7947a) addendum circle
7948b) dedundum circle
7949c) pitch circle
7950d) clearance circle
795199. which of the following is incorrect relationship for gears
7952a) circular pitch X diameteral pitch = 3.14
7953374
7954b) module = pcd/No of teeth
7955c) dedendum = 1.157 module
7956d) addedendum = 2.157 module
7957100. The train value of a gear train is
7958a) equal to velocity ratio
7959b) reciprocal of velocity ratio
7960c) >1
7961d) <1
7962375
79631. The minimum number of teeth on the pinion which will mesh with any gear without interference for 20° full depth involute teeth will be
7964a) 12
7965b) 14
7966c) 18
7967d) 24
79682. The coriolis component of acceleration leads the sliding velocity by
7969a) 45 degree
7970b) 90 degree
7971c) 135 degree
7972d) 180 degree
79733. The magnitude of linear velocity of a point B on a link AB relative to point A is (where ω = Angular velocity of the link AB)
7974a) ω x AB
7975b) ω (AB)2
7976c) ω (AB)2
7977d) ω (AB)2
79784. The mechanism in which two are turning pairs and two are sliding pairs, is called a
7979a) double slider crank chain
7980b) crank slider
7981c) four bar
7982d) beam engine
7983376
79845. Which of the following is an inversion of a double slider crank chain?
7985a) Oldham's coupling
7986b) beam engine
7987c) engine mechanism
7988d) elliptical trammel
79896. Which of the following is a turning pair?
7990a) Piston and cylinder of a reciprocating steam engine
7991b) shaft with collars at both ends fitted into a circular hole
7992c) lead screw
7993d) Ball and a socket joint
79947. The method of obtaining different mechanisms by fixing in turn different links in a kinematic chain, is known as
7995a) structure
7996b) machine
7997c) inversion
7998d) compound mecahnism
79998. The mechanismm used in a petrol engine is
8000a) crank mechanism
8001b) slider mechanism
8002c) crank slider mechanism
8003d) circular mechanism
80049. The coriolis component of acceleration is taken into account for
8005377
8006a) slider crank mechanism
8007b) four bar chain mechanism
8008c) quick return motion mechanism
8009d) straight line mechanism
801010. According to Kennedy's theorem, if three bodies move relatively to each other, their instantaneous centres will lie on a
8011a) straight line
8012b) parabolic curve
8013c) triangle
8014d) triangle
801511. The relation l = (j + 2) apply only to kinematic chains in which lower pairs are used. This may be used to kinematic chains in which higher pairs are used, but each higher pair may be taken as equivalent to
8016a) one lower pair and two additional links
8017b) two lower pairs and one additional link
8018c) two lower pairs and two additional links
8019d) any one of these
802012. The relation between number of links (l) and number of joints (j) in a kinematic chain is
8021a) l = (j + 2)
8022b) l = 2/3 (j + 2)
8023c) l = (j + 2)
8024d) l = j + 4
802513. In a pantograph, all the pairs are
8026a) turning pairs
8027378
8028b) sliding pairs
8029c) spherical pairs
8030d) self-closed pairs
803114. The velocity of a body moving with simple harmonic motion is __________ at the mean position
8032a) zero
8033b) unity
8034c) minimum
8035d) maximim
803615. The magnitude of velocities of the points on a rigid link is
8037a) directly proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
8038b) directly proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
8039c) inversely proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre
8040d) inversely proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre
804116. The mechanism consisting of three turning pairs and one sliding pair, is called a
8042a) single slider crank chain
8043b) single slider crank chain
8044c) crank and slotted lever quick return motion mechanism
8045d) all above
8046379
804717. When the nature of contact between the elements of a pair is such that one element can turn about the other by screw threads, the pair is known as a
8048a) screw pair
8049b) spherical pair
8050c) turning pair
8051d) sliding pair
805218. Which of the following statement is correct as regard to the difference between a machine and a structure?
8053a) The parts of a machine move relative to one another, whereas the members of a structure do not move relative to one another
8054b) The links of a machine may transmit both power and motion, whereas the members of a structure transmit forces only
8055c) A machine transforms the available energy into some useful work, whereas in a structure no energy is transformed into useful work
8056d) all of the above
805719. he dedendum circle diameter is equal to (where φ = Pressure angle)
8058a) pitch circle dia. x cos φ
8059b) addendum circle dia. x cos φ
8060c) clearance circle dia. x cos φ
8061d) pitch circle dia. x sin φ
806220. Pitch point of a cam is
8063a) a point on the pitch curve having minimum pressure angle
8064b) a point on the pitch curve having maximum pressure angle
8065c) any point on the pitch curve
8066380
8067d) any point on the prime circle
806821. Which of the following mechanism is an approximate straight line motion mechanism?
8069a) Watt's mechanism
8070b) Watt's mechanism
8071c) Robert's mechanism
8072d) all of above
807322. The maximum velocity of a particle moving with simple harmonic motion is
8074a) ω
8075b) ωr
8076c) ω2r
8077d) ω/r
807823. In gears, interference takes place when
8079a) the tip of a tooth of a mating gear digs into the portion between base and root circles
8080b) gears do not move smoothly in the absence of lubrication
8081c) pitch of the gears is not same
8082d) gear teeth are undercut
808324. The two links OA and OB are connected by a pin joint at O. If the link OA turns with angular velocity ω1 rad/s in the clockwise direction and the link OB turns with angular velocity ω2 rad/s in the anti-clockwise direction, then the rubbing velocity at the pin joint O is (where r = Radius of the pin at O)
8084a) ω1.ω2.r
8085b) ( ω1 - ω2)r
8086c) ( ω1 + ω2)r
8087d) ( ω1 - ω2)2r
8088381
808925. The size of cam depends upon
8090a) base circle
8091b) base circle
8092c) prime circle
8093d) pitch curve
809426. The acceleration of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by
8095a) ω2R cos θ
8096b) ω2(R - r1)cos θ
8097c) ω2(R - r1)sin θ
8098d) ω2r1 sin θ
809927. The sense of coriolis component 2 ωv is same as that of the relative velocity vector v rotated at
8100a) 45° in the direction of rotation of the link containing the path
8101b) 45° in the direction of rotation of the link containing the path
8102c) 90° in the direction of rotation of the link containing the path
8103d) 180° in the direction opposite to the rotation of the link containing the path
810428. A point B on a rigid link AB moves with respect to A with angular velocity ω rad/s. The total acceleration of B with respect to A will be equal to
8105a) vector sum of radial component and coriolis component
8106b) vector sum of radial component and coriolis component
8107c) vector sum of radial component and tangential component
8108d) vector difference of radial component and tangential component
8109382
811029. The Ackerman steering gear mechanism is preferred to the Davis steering gear mechanism, because
8111a) whole of the mechanism in the Ackerman steering gear is on the back of the front wheels
8112b) the Ackerman steering gear consists of turning pairs
8113c) the Ackerman steering gear consists of turning pairs
8114d) both (a) and (b)
811530. In a gear having involute teeth, the normal to the involute is a tangent to the
8116a) pitch circle
8117b) base circle
8118c) addendum circle
8119d) dedendum circle
812031. The component of the acceleration, parallel to the velocity of the particle, at the given instant is called
8121a) radial component
8122b) tangential component
8123c) coriolis component
8124d) resultant
812532. The example of successfully constrained motion is a
8126a) motion of an I.C. engine valve
8127b) motion of the shaft between a foot-step bearing
8128c) piston reciprocating inside an engine cylinder
8129d) all of the above
813033. The cam follower generally used in air-craft engines is
8131a) knife edge follower
8132383
8133b) flat faced follower
8134c) spherical faced follower
8135d) roller follower
813634. The following are the data for two crossed helical gears used for speed reduction
8137Gear I : Pitch circle diameter in the plane of rotation 80 mm and helix angle 300
8138GEAR II : Pitch circle diameter in the plane of rotation 120 mm and helix angle 22.50
8139a) 1200
8140b) 900
8141c) 875
8142d) 720
814335. In a circular arc cam with roller follower, the acceleration in any position of the lift will depend only upon
8144a) total lift, total angle of lift, minimum radius of cam and cam speed
8145b) radius of circular arc, cam speed, location of centre of circular arc and roller diameter
8146c) mass of cam follower linkage, spring stiffness and cam speed
8147d) total lift, centre of gravity of the cam and cam speed
814836. When the connection between the two elements is such that only required kind of relative motion occurs, it is known as
8149a) force closed
8150b) self-closed pair.
8151c) open
8152d) both a and b
815337. The Whitworth quick return motion mechanism is formed in a slider crank chain when the
8154384
8155a) coupler link is fixed
8156b) longest link is a fixed link
8157c) slider is a fixed link
8158d) smallest link is a fixed link
815938. An automobile steering gear is an example of
8160a) sliding pair
8161b) rolling pair
8162c) lower pair
8163d) higher pair
816439. The gear train usually employed in clocks is a
8165a) simple gear train
8166b) reverted gear train
8167c) sun and planet gear
8168d) differential gear
816940. The working depth of a gear is the radial distance from the
8170a) pitch circle to the bottom of a tooth
8171b) pitch circle to the top of a tooth
8172c) top of a tooth to the bottom of a tooth
8173d) addendum circle to the clearance circle
8174385
8175Machining Processes and Metrology
81761. Built-up edge formation decreases under the conditions listed below EXCEPT
8177a) At low cutting speeds
8178b) Using large positive rake angle
8179c) With sharper tool
8180d) Using cutting fluid
81812. During turning of mild steel work material, the maximum temperature is observed at
8182a) Primary deformation zone
8183b) tool and chip interface
8184c) tool-flank and work interface
8185d) machined sub-surface
81863. Which of the following DO NOT influence the material removal rate in Electrical Discharge Machining process
8187(i) Hardness of the work piece material (ii) Melting temperature of the work piece material (iii) Hardness of tool material (iv) Discharge current and frequency
8188a) (i) and (II)
8189b) (i) and (iii)
8190c) (iii) and (iv)
8191d) (i), (ii) and (iii)
81924. The angle of a twist drill that determines its rake angle is
8193a) lip relief angle
8194b) chisel edge angle
8195c) helix angle
8196d) point angle
8197386
81985. Which one of the following statements related to grinding process is INCORRECT
8199a) Grinding wheels made up of finer abrasive grains produce better surface finish
8200b) Abrasive grains tend to fracture frequently during the grinding process
8201c) Specific energy in grinding is higher than that in turning
8202d) cutting speed in grinding process is much lower than that in face milling
82036. Two cuttng tools are been compared for a machining operation. The tool life equations are (i) Carbide tool: VT^1.6 = 3000 (ii) HSS tool: VT^0.6 = 200. In these equations, V is the cutting speed in m/min and T is the tool life in min. The carbide tool will provide higher tool life if the cutting speed in m/min exceeds
8204a) 15.0
8205b) 39.4
8206c) 49.3
8207d) 60.0
82087. In water jet machining, the water jet is issued through a 0.3mm diameter orifice at a pressure of 400 MPa. THe density of water is 1000 kg/cubic meter. The coefficient of discharge is 1.0. Neglecting all loses during water jet formation through the orifice, the power of the water in kW is _________
8209a) 25.3
8210b) 50.6
8211c) 75.9
8212d) 101.2
82138. In orthogonal turning of a bar of 100mm diameter with a feed of 0.25mm/rev, depth of cut of 4mm and cutting velocity of 90 m/min, it is observed that the main (tangential) cutting force is perpendicular to the friction force acting at the chip-tool interface. If the main (tangential) cutting force is 1500 N, the orthogonal rake angle of the cutting tool is ___________
8214a) ZERO Degrees
8215387
8216b) 3.58 Degrees
8217c) 5.0 Degrees
8218d) 7.16 Degrees
82199. In orthogonal turning of a bar of 100mm diameter with a feed of 0.25mm/rev, depth of cut of 4mm and cutting velocity of 90 m/min, it is observed that the main (tangential) cutting force is perpendicular to the friction force acting at the chip-tool interface. If the main (tangential) cutting force is 1500 N, the normal force acting at the chip-tool interface is ________
8220a) 1000 N
8221b) 1500 N
8222c) 2000 N
8223d) 2500 N
822410. A disc of 200mm outer and 80mm inner diameter is faced at a feed of 0.1 mm/rev with a depth of cut of 1mm. The facing operation is undertaken at a constant cutting speed of 90m/min in a CNC lathe. The main (tangential) cutting force is 200 N. Neglecting the contribution of feed force towards cutting power, the specific cutting energy is _________
8225a) 0.2 Joules/cubic mm
8226b) 2.0 Joules/cubic mm
8227c) 200 Joules/cubic mm
8228d) 2000 Joules/cubic mm
822911. A disc of 200mm outer and 80mm inner diameter is faced at a feed of 0.1 mm/rev with a depth of cut of 1mm. The facing operation is undertaken at a constant cutting speed of 90m/min in a CNC lathe. The main (tangential) cutting force is 200 N. Assuming approach and over-travel of the cutting tool to be Zero, the machining time is __________
8230a) 2.93 minutes
8231b) 5.86 minutes
8232c) 6.66 minutes
8233d) 13.33 minutes
8234388
8235Machining Processes and Metrology
82361. Segmental chips are formed during machining
8237a) cast iron
8238b) high speed steel
8239c) mild steel
8240d) high carbon steel
82412. A single point thread cutting tool should ideally have
8242a) point angle
8243b) zero rake angle
8244c) positive rake angle
8245d) negative rake angle
82463. Cast iron during machining produces
8247a) discontinuous chips
8248b) continuous chips
8249c) continuous chips with built-up-edge
8250d) none of these
82514. When the cutting edge of the tool is dull, then during machining
8252a) discontinuous chips are formed
8253b) continuous chips with built-up edge are formed
8254c) continuous chips are formed
8255d) no chips are formed
8256389
82575. The tool made of cemented carbide wear out faster at
8258a) fast speeds
8259b) slow speeds
8260c) medium speeds
8261d) very fast speeds
82626. The silicon carbide abrasive is chiefly used for grinding
8263a) ceramic
8264b) cast iron
8265c) cemented carbide
8266d) all of these
82677. Side rake angle of a single point cutting tool is the angle
8268a) between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base
8269b) by which the face of the tool is inclined towards back
8270c) by which the face of the tool is inclined sideways
8271d) between the surface of the flank immediately below the point and a plane at right angles to the centre line of the point of the tool
82728. The cutting tool in a milling machine is mounted on
8273a) spindle
8274b) column
8275c) knee
8276d) arbor
82779. Drilling is an example of
8278390
8279a) orthogonal cutting
8280b) uniform cutting
8281c) oblique cutting
8282d) simple cutting
828310. Crater wear occurs mainly on the
8284a) cutting edge only
8285b) face of the cutting tool at a short distance from the cutting edge only
8286c) nose part, front relief face and side relief face of the cutting tool
8287d) front face only
828811. A push broach as compared to pull broach
8289a) has less number of teeth
8290b) removes less material for each pass of the tool
8291c) is short and stocky
8292d) all of the above
829312. The lip angle of a single point tool is usually
8294a) 40° to 60°
8295b) 20° to 40°
8296c) 60° to 80°
8297d) none of these
829813. A twist drill is a
8299a) end cutting tool
8300b) side cutting tool
8301c) front cutting tool
8302391
8303d) none of these
830414. The maximum production of small and slender parts is done by
8305a) sliding head stock automatic lathe
8306b) multispindle automatic lathe
8307c) watch maker's lathe
8308d) capastan lathe
830915. The method of grinding used to produce a straight or tapered surface on a workpiece, is
8310a) surface grinding
8311b) internal cylindrical grinding
8312c) form grinding
8313d) external cylindrical grinding
831416. Gear lapping is an operation
8315a) prior to heat treatment
8316b) after heat treatment
8317c) for gear reconditioning
8318d) none of these
831917. In up milling, the thickness of chip is
8320a) minimum at the beginning of the cut and maximum at the end of the cut
8321b) maximum at the beginning of the cut and minimum at the end of the cut
8322c) uniform throughout the cut
8323d) none of these
832418. The facing is an operation of
8325392
8326a) bevelling the extreme end of a workpiece
8327b) embossing a diamond shaped pattern on the surface of a workpiece
8328c) reducing the diameter of a workpiece over a very narrow surface
8329d) machining the ends of a workpiece to produce a flat surface square with the axis
833019. The lathe spindles are usually made hollow and provided with
8331a) internal taper
8332b) internal and external taper
8333c) external taper
8334d) no taper
833520. Which of the following statement is incorrect with reference of lathe cutting tools?
8336a) The base is that surface of the shank which bears against the support and takes tangent pressure of the cut
8337b) The flank of the tool is the surface or surfaces below and adjacent to the cutting edges
8338c) The nose is the corner, arc or chamfer joining the side cutting and the end cutting edges
8339d) The heel is that part of the tool which is shaped to produce the cutting edges and face
834021. In machining metals, chips break due to __________ of work material.
8341a) work hardening
8342b) toughness
8343c) elasticity
8344d) ductility
834522. The lead screw of a lathe has __________ threads.
8346a) multi-start square
8347b) double start square
8348393
8349c) single start square
8350d) any one of these
835123. Lapping is an operation of
8352a) making a cone-shaped enlargement of the end of a hole
8353b) smoothing and squaring the surface around a hole
8354c) sizing and finishing a small diameter hole
8355d) producing a hole by removing metal along the circumference of a hollow cutting tool
835624. Which of the following parameters influence the axial feed rate in centreless grinding?
8357a) Angle between the axes of grinding and regulating wheels
8358b) Speed of the regulating wheel
8359c) Regulating wheel diameter
8360d) all of the above
836125. The machining of titanium is difficult due to
8362a) chemical reaction between tool and work
8363b) high thermal conductivity of titanium
8364c) low tool-chip contact area
8365d) none of these
836626. High speed steel drills can be operated at about __________ the speed of high carbon steel drills.
8367a) four times
8368b) one-fourth
8369c) one-half
8370d) double
8371394
837227. The rear teeth of a broach
8373a) remove minimum metal
8374b) perform burnishing operation
8375c) remove maximum metal
8376d) remove no metal
837728. In hot machining, tool is made of
8378a) stainless steel
8379b) tungsten carbide
8380c) brass or copper
8381d) diamond
838229. Grinding wheels should be tested for balance
8383a) only at the time of manufacture
8384b) before starting the grinding operation
8385c) at the end of grinding operation
8386d) occasionally
838730. In ultrasonic machining, the metal is removed by
8388a) using abrasive slurry between the tool and work
8389b) direct contact of tool with the work
8390c) maintaining an electrolyte between the work and tool in a very small gap between the two
8391d) erosion caused by rapidly recurring spark discharges between the tool and work
839231. In a shaper, the length of stroke is increased by
8393a) increasing the centre distance of bull gear and crank pin
8394395
8395b) increasing the length of the arm
8396c) decreasing the centre distance of bull gear and crank pin
8397d) decreasing the length of the slot in the slotted lever
839832. In metal machining, the work-tool contact zone is a zone where heat is generated due to
8399a) friction between the moving chip and the tool face
8400b) burnishing friction
8401c) plastic deformation of metal
8402d) none of the above
840333. The method of centreless grinding used to produce taper is
8404a) through feed grinding
8405b) infeed grinding
8406c) endfeed grinding
8407d) any one of these
840834. The angle made by the face of the tool and the plane parallel to the base of cutting tool is called
8409a) cutting angle
8410b) rake angle
8411c) clearance angle
8412d) lip angle
841335. Which of the following statement is correct for orthogonal cutting system?
8414a) The cutting edge clears the width of the workpiece on either ends.
8415b) The cutting edge of the tool is perpendicular to the direction of tool travel.
8416c) The chip flows over the tool face and the direction of the chip flow velocity is normal to the cutting edge.
8417396
8418d) all of the above
841936. The abrasive recommended for grinding materials of high tensile strength is
8420a) silicon carbide
8421b) aluminium oxide
8422c) sand stone
8423d) diamond
842437. Crater wear is predominant in
8425a) tungsten carbide tools
8426b) carbon tool steels
8427c) high speed steel tools
8428d) ceramic tools
842938. The factor responsible for the formation of continuous chips with built up edge is
8430a) high cutting speed and small rake angle
8431b) high cutting speed and large rake angle
8432c) low cutting speed and small rake angle
8433d) low cutting speed and large rake angle
843439. Glazing in grinding wheels can be decreased by
8435a) using a softer wheel or by decreasing the wheel speed
8436b) using a softer wheel or by increasing the wheel speed
8437c) using a harder wheel or by increasing the wheel speed
8438d) using a harder wheel or by decreasing the wheel speed
843940. The cutting speed is minimum while machining __________ with a high speed steel tool.
8440397
8441a) cast iron
8442b) brass
8443c) mild steel
8444d) aluminium
844541. In centreless grinding, the surface speed of regulating wheel is
8446a) 5 to 15 m/min
8447b) 60 to 90 m/min
8448c) 15 to 60 m/min
8449d) 90 to 120 m/min
845042. A process of removing metal by pushing or pulling a cutting tool is called
8451a) up milling
8452b) down milling
8453c) forming
8454d) broaching
845543. An important geometrical quantity in the cutting of metals which can be used as a criterion for machinability of metals is
8456a) feed rate
8457b) shear angle
8458c) cutting speed
8459d) tool geometry
846044. In metal cutting, use of low feeds and high cutting speeds is desired when the objective is
8461a) surface finish
8462b) dry machining
8463398
8464c) high metal removal rate
8465d) use of soft cutting tool
846645. The angle on which the strength of the tool depends is
8467a) cutting angle
8468b) lip angle
8469c) rake angle
8470d) clearance angle
847146. Larger than 15° side cutting edge angle
8472a) decreases tool life
8473b) increases tool life
8474c) produces chipping and decreases tool life
8475d) results in excessive stress concentration and greater heat generation
847647. The swing diameter over the bed is __________ the height of the centre measured from the bed of the lathe
8477a) twice
8478b) thrice
8479c) equal to
8480d) one and a half
848148. Which of the following operations can be performed with milling cutters?
8482a) cutting external screw threads
8483b) cutting teeth of spur gears
8484c) cutting key ways on shafts
8485d) all of these
8486399
848749. In grinding irregular, curved, tapered, convex and concave surfaces, the grinder used is
8488a) tool and cutter grinder
8489b) cylindrical grinder
8490c) internal grinder
8491d) surface grinder
849250. Down milling is also called
8493a) end milling
8494b) climb milling
8495c) conventional milling
8496d) face milling
849751. The hardness of a grinding wheel is specified by
8498a) Rockwell hardness number
8499b) Brinell hardness number
8500c) Vickers pyramid number
8501d) letter of alphabet
850252. Any number of equal divisions can be obtained on milling machine by
8503a) simple indexing
8504b) differential indexing
8505c) direct indexing
8506d) compound indexing
850753. The type of tool used on lathe, shaper and planer is
8508a) two point cutting tool
8509400
8510b) multi-point cutting tool
8511c) three point cutting tool
8512d) single point cutting tool
851354. In order to grind soft material
8514a) fine grained grinding wheel is used
8515b) medium grained grinding wheel is used
8516c) coarse grained grinding wheel is used
8517d) any one of these
851855. The type of reamer used for reaming operation in a blind hole, is
8519a) straight fluted reamer
8520b) left hand spiral fluted reamer
8521c) right hand spiral fluted reamer
8522d) any one of these
852356. The depth of cut in drilling is __________ the drill diameter.
8524a) one-half
8525b) equal to
8526c) one-fourth
8527d) double
852857. In a single point tool, the angle between the surface of the flank immediately below the point and a line drawn from the point perpendicular to the base, is known as
8529a) side rake angle
8530b) side relief angle
8531c) end relief angle
8532401
8533d) back rake angle
853458. A set of eight form relieved milling cutters for each module is provided to enable cutting of gears of different
8535a) width of gears
8536b) number of teeth
8537c) types of gears
8538d) materials
853959. The purpose of jigs and fixtures is to
8540a) increase machining accuracy
8541b) facilitate interchangeability
8542c) decrease expenditure on quality control
8543d) all of these
854460. The trade name of a non-ferrous cast alloy composed of cobalt, chromium and tungsten is called
8545a) diamond
8546b) ceramic
8547c) cemented carbide
8548d) stellite
854961. The velocity of tool along the tool face is known as
8550a) chip velocity
8551b) shear velocity
8552c) cutting velocity
8553d) mean velocity
8554402
855562. The grinding operaion is a
8556a) forming operation
8557b) shaping operation
8558c) surface finishing operation
8559d) dressing operation
856063. The machine tool guideways are of
8561a) flat type
8562b) dovetail type
8563c) V-type
8564d) any one of these
856564. A measurement system only includes operators and gauges
8566a) Can't predict
8567b) False
8568c) Always True
8569d) May be true or false
857065. Precision is related to the accuracy of the measurements
8571a) True
8572b) Always False
8573c) May be true or false
8574d) can't predict
857566. Which one of the following methods produces gear by generating process
8576a) Hobbing
8577b) Casting
8578403
8579c) Punching
8580d) Milling
8581e) Broaching
858267. In metrology, a feeler gauge is used to check
8583a) Radius
8584b) Screw pitch
8585c) Surface roughness
8586d) Thickness of clearance
858768. In surface roughness measurements, the term "secondary texture" represents ______
8588a) roughness
8589b) Flaw
8590c) Lay direction
8591d) Waviness
859269. Tomlinson's surface meter and Taylor Hobson Talysurf are _______ instruments
8593a) surface roughness measuring
8594b) lay direction measuring
8595c) Surface waviness measuring
859670. Slip gauges are _________standards
8597a) wave length
8598b) secondary
8599c) Line
8600d) end
8601404
860271. Dial gauge is a ________
8603a) linear measring instrument
8604b) Angular measuring instrument
8605c) Surface measuring instrument
8606d) None of these
860772. Among the various terminologies related to surface roughness, 'Ra' represents _______
8608a) Roughness average
8609b) Root Mean square value
8610c) Mean roughnes depth
8611d) sampling length
861273. The least measurement that can be detected by a measuring instrument is _______
8613a) accuracy
8614b) Sensitivity
8615c) calibration
8616d) Precision
861774. The closeness of the measured value to the actual value is ________
8618a) Accuracy
8619b) Precision
8620c) Repeatability
8621d) Sensitivity
862275. The comparators eliminate the __________
8623a) Measuring time
8624b) need for machining
8625405
8626c) surface roughness
8627d) sourface waviness
862876. The scientist 'Carl Edvard Johansson' invented ________
8629a) Sine bar
8630b) Comparators
8631c) Slip gauges
8632d) Surface table
863377. Primary standards are kept at all leading industries across the globe
8634a) True
8635b) False
863678. The closeness among the measured value is ___________
8637a) Accuracy
8638b) Precision
8639c) Repeatability
8640d) Calibration
864179. The outer most profile circle of a gear is ________
8642a) pitch circle
8643b) Addendum circle
8644c) Dedendum circle
864580. In gears, the face width is the width of ___________
8646a) Top land
8647b) Face
8648406
8649c) Bottom land
8650d) clearance
865181. In gears, the inner most profile circle is _________
8652a) Addendum
8653b) dedundum
8654c) Pitch
8655d) Clearance
865682. Milling machine uses a ___________
8657a) Single point cutting tool
8658b) Diamond tool
8659c) Multipoint cutting tool
8660d) Drill bit
866183. If the milling cutter axis is parallel to the surface generated, it comes under the category of _________
8662a) face milling
8663b) peripheral milling
8664c) end milling
8665d) straddle miling
866684. _____________milling refers to the use of two or more milling cutters mounted on the same arbor
8667a) Profile milling
8668b) gang milling
8669c) End milling
8670d) form milling
8671407
867285. The measured forces/force in Merchant Circle diagram are/is _______
8673a) Friction force
8674b) shear force and Cutting force
8675c) Cutting force and tangential force
8676d) Normal force
867786. In grinding wheel designation, the structure of the grinding wheel is represented by ________
8678a) an alphabet
8679b) a number
8680c) a special character
868187. In milling machine operations, 'T-slots' are made by ______________
8682a) Form cutters
8683b) T-Slot milling cutters
8684c) End mill and T-slot milling cutter
8685d) Profile milling cutter
868688. Simple indexing mechanism consists of _____________
8687a) Worm, worm gear assembly
8688b) Index plates
8689c) Worm worm gear assembly and Index plates
8690d) spur gear and worm gear assembly
869189. In a lathe, 'Half-nut' mechanism is engaged during ________ operation
8692a) taper turning
8693408
8694b) Step turning
8695c) Facing and turning
8696d) Thread cutting
869790. In lathe turning parameters, another name for depth of cut is __________
8698a) longtitudinal feed
8699b) facing
8700c) cross feed
8701d) speed
870291. In a lathe, the best possible way to hold irregular work piece is by using a ___________
8703a) 3-Jaw self centering chuck
8704b) 4-jaw independent chuck
8705c) face plates and clamps
8706d) Magnetic chuck
870792. In shaper, the clapper box mechanism _____
8708a) lifts the cutting tool vertically up during cutting stroke
8709b) lifts the cutting tool vertically up during return stroke
8710c) Lowers the shaper table
8711d) Swivels the cutting tool during the return stroke
871293. While a drill bit drills a hole, the chips are removed through _________
8713a) the other side of the work piece
8714b) the flutes
8715c) the shank
8716d) land
8717409
871894. A boring tool __________ a hole
8719a) generates
8720b) super finishes
8721c) enlarges
8722d) all the above
872395. Choose the most appropriate option to match the terminology "rise per teeth".
8724a) Broach tool
8725b) grinding wheeel abrasives
8726c) Angular milling cutter
8727d) Milling cutter
872896. Merchant Circle Diagram is ____________
8729a) an analytical approach find the friction force, Normal friction force, Shear force and Normal shear force.
8730b) a Finite element method
8731c) a graphical approach to find the cutting force and tangential force
8732d) a graphical approach to find the friction force, Normal friction force, Shear force and Normal shear force.
873397. Taylor's tool life equation optimises _________
8734a) Cutting speed and tool life
8735b) tool life and cutting angle
8736c) cutting speed and end relif angle
8737d) none of the above
873898. In a shaper, the Pawl mechanism is to provide ____________
8739410
8740a) feed movement to the tool
8741b) feed movement to the table
8742c) Swivel the tool head
8743d) Rotate the bull gear
874499. In metrology, angular measurements are made using __________
8745a) sine bar alone
8746b) surface platesand slip gauges
8747c) Sine bar and slip gauges
8748d) Slip gauge alone
8749100. In metrology, calibration is performed to __________
8750a) manufacture the equipments
8751b) measure the repeatabiity of the instrument.
8752c) measure the surface roughness
8753d) to fix the errors
8754Machining Processes and Metrology (Fresh 40 questions)
87551. Double helical gears are also known as _________
8756a) Herringbone gears
8757b) double bevel gears
8758c) rack and pinion geras
8759d) Conical gears
87602. _________ gears transmit power between two perpendicular shafts
8761411
8762a) Conical
8763b) Spur
8764c) Bevel
8765d) helical
87663. ____________ is mandatory for electrochemical machining
8767a) copper material
8768b) Electrolyte
8769c) brass material
8770d) water bath
87714. The energy domain in water jet machining ang abrasive jet machining is different
8772a) True
8773b) False
8774c) It depends on the work piece material
8775d) It depends on the jet pressure
87765. _________ is an essential part in abrasive jet machining.
8777a) gear pump
8778b) gears
8779c) Nozzle
8780d) oxygen cylinder
87816. In lathe, the half nut mechanism is to engage automatic _________ movement.
8782a) speed
8783b) depth of cut
8784c) speed and depth of cut
8785412
8786d) feed
87877. In conventional machining process, the tool is ______ than the work piece.
8788a) softer
8789b) Smaller
8790c) Longer
8791d) Harder
87928. Gear honing is a collective name for both gear finishing and gear forming operations.
8793a) False
8794b) Cannot judge
8795c) True, but depends on the gear material
8796d) Always true
87979. EDM stands for _____________
8798a) Electric Dielectric Machining
8799b) Electro Discharge Machining
8800c) Energy Discharge Machining
8801d) None of these answers
880210. __________ comes under non-conventional machining process
8803a) turning
8804b) grinding
8805c) lapping
8806d) drilling
880711. In laser beam machining, the work piece comes as a part of the electrical circuit
8808413
8809a) True
8810b) Partially true
8811c) partially false
8812d) always False
881312. Prolonged usage of a loaded grinding wheel produces ___________
8814a) grinding wheel fracture
8815b) glazed surface
8816c) superfinshed work piece
8817d) dressed grinding wheel.
881813. In broaching operation, RPT means ______________
8819a) Rotations Per Tooth
8820b) Rise Per Tooth
8821c) Radius Per Tooth
8822d) Robustness Per Tooth
882314. In a milling machine, the position of _________ determines the type of milling machine
8824a) work table
8825b) radial arm
8826c) column
8827d) Arbor
882815. Can a drill bit produce square holes?
8829a) Yes, with an ordinary drill bit
8830b) Yes, with special drill bits
8831c) Yes, with a simple indexing mechanism
8832414
8833d) Never
883416. In shaper, the maximum pssible one side travel of the ram is temed as ____________
8835a) Stroke length
8836b) Skew length
8837c) Indexing length
8838d) Pitch circle diameter
883917. Rack is type of gear with ______ radius
8840a) Finite, but less than 50mm
8841b) infinite
8842c) 60mm
8843d) 60.55mm
884418. The use of metal working fluids
8845a) increase the tool life
8846b) produce better surface finish
8847c) prevent rise in temperature
8848d) All the options are correct
884919. Which of the following is added to the cutting fluids so that soapy film is produced between the workpiece and tool and chip and tool face?
8850a) Sulphur
8851b) Chlorine
8852c) Both Sulphur and Chlorine
8853d) None of the answers
8854415
885520. Usually no cutting oil is used in
8856a) Broaching
8857b) Planning and shaping
8858c) Thread rolling
8859d) Honing
886021. Which one of the following process is not a machining process?
8861a) Planing
8862b) Boring
8863c) Turning
8864d) Forging
886522. What is the disadvantage of the machining processes?
8866a) Machining processes cannot produce complex geometries.
8867b) Machining processes cannot produce dimensions to very close tolerances.
8868c) In machining processes there is loss of material in the form of chips.
8869d) Only a few numbers of materials can be machined
887023. Which one of the following is NOT a guideline for the designing of the machined parts?
8871a) Whenever possible, machining processes should be used to manufacture a part.
8872b) Sharp corners and sharp points in the cutting tool should be avoided.
8873c) Avoiding interrupted cuts, undercutting.
8874d) Providing relief space for the burr removal.
887524. Which of the following tool is BEST used for turning?
8876a) Multi point cutting tool
8877b) Single point cutting tool
8878416
8879c) Hand tool
8880d) End cutting tool
888125. Turning is an operation in which
8882a) Work piece rotates and tool reciprocates
8883b) Work piece is fixed and tool rotates and reciprocates
8884c) Tool is fixed and work piece reciprocates
8885d) Tool rotates and work piece reciprocates
888626. In turning, the metal removal takes place by_____________
8887a) Plastic deformation
8888b) Plastic deformation and shearing
8889c) Shearing
8890d) Elastic deformation
889127. In the drilling process, the drill bit should be always _____________to the drilling
8892surface.
8893a) Parallel
8894b) Perpendicular
8895c) Angular (45 degrees)
8896d) None of these answers
889728. Which is the costliest process for making round holes?
8898a) Boring
8899b) Reaming
8900c) Drilling
8901d) Perforatting
8902417
890329. Accuracy of the drilled holes depends on_____________
8904a) correctness of drill sharpening
8905b) Thermal coefficient of expansion of material
8906c) Drill bushing
8907d) All the answers are correct
890830. In reamed holes, what is the recommended tolerance for the hole diameter over 50 mm?
8909a) ± 0.025
8910b) ± 0.05
8911c) ± 0.08
8912d) All the answers are correct
891331. In milling operation, materials having higher hardness require the cutting speed and
8914feed per tooth.
8915a) Higher cutting speed and reduced feed
8916b) Lower cutting speed and increased
8917feed
8918c) Lower cutting speed and reduced feed
8919d) Higher cutting speed and increased
8920feed
892132. Which type cutters are more prone to vibration, chatter, and deflection of tool and
8922machine components?
8923a) Small size
8924b) Large size
8925c) Both
8926418
8927d) None of the answers
892833. In peripheral milling, the machining is performed by cutting edges
8929a) On both the ends of the cutter
8930b) On the outside periphery of the cutter
8931c) On the inner periphery of the cutter
8932d) None of the answers
893334. Which one milling process is an economical approach if product design permits
8934stacking or slicing operations?
8935a) Plain milling
8936b) Face milling
8937c) Form milling
8938d) Spot facing
893935. Which type of materials is processed by milling process?
8940a) Ferrous
8941b) Nonferrous
8942c) Both ferous and non ferrous
8943d) None of the answers
894436. In planning the motion is accomplished by the ______________.
8945a) Work piece
8946b) Tool
8947c) Cross slide
8948d) Arbor
8949419
895037. Inaccessible surfaces those cannot be machined with other types of equipment can be
8951produced by __________.
8952a) Turning
8953b) Broaching
8954c) Grinding
8955d) Shaping
895638. Which of the following is not a design recommendation for broaching?
8957a) A part to be broached should be designed so that it can be easily located
8958b) The forged parts should be kept as close dimension as possible, allowing only minimum stock for finishing
8959c) Thin wall sections are to be provided
8960d) If similar broaching operation is to be carried out for a group of parts, then it is advisable to design the parts in such a way that same broaching tool is used
896139. What is broaching?
8962a) Broaching is the cutting of a machinable material using single point cutting tool by moving the tool linearly relative to the work in the direction of tool axis
8963b) Broaching is the cutting of a machinable material using multiple tooth cutting tools
8964by moving the tool linearly relative to the work in the direction of tool axis
8965c) Broaching is the cutting of a machinable material using multiple tooth cutting tools
8966by moving the tool perpendicularly relative to the work in the direction of tool axis
8967d) None of these answers
896840. Which of the following does not require broaching operation?
8969a) Square, circular or irregular holes
8970b) Gears and ratchets
8971c) Cam forms
8972420
8973d) None of the answers
8974421
8975Materials Engineering & Technology
89761. Which one of the following metals is commonly alloyed with iron to improve its corrosion resistance?
8977a) Co
8978b) Cr
8979c) Ti
8980d) Nb
89812. The number of slip systems in a metal with FCC crystal structureis
8982a) 4
8983b) 6
8984c) 8
8985d) 12
89863. The material property which depends only on the basic crystal structure is
8987a) Fatigue strength
8988b) Work hardening
8989c) Fracture strength
8990d) Elastic constant
89914. What is a surface imperfection, which separates crystals of different orientations in a poly-crystalline aggregate, called?
8992a) Edge dislocation
8993b) Stacking fault
8994c) Grain boundary
8995d) Screw dislocation
8996422
89975. The B.C.C. and H.C.P. metals undergo plastic deformation by:
8998a) Slip
8999b) Twinning
9000c) Edge dislocation
9001d) Twinning in combination with slip
90026. Martensite is a super-saturated solution of carbon in
9003a) Alpha iron
9004b) Beta iron
9005c) Gamma iron
9006d) Delta iron
90077. Which one of the following cast irons consists of carbon in rosette form?
9008a) White cast iron
9009b) Gray cast iron
9010c) Malleable cast iron
9011d) Nodular cast iron
90128. Monel metal is an alloy of
9013a) Iron and carbon
9014b) Copper and zinc
9015c) Aluminium and copper
9016d) Copper and nickel
90179. Cutting tool material 18-4-1 HSS has which one of the following compositions?
9018a) 18% W, 4% Cr, 1% V
9019b) 18% Cr, 4% W, 1% V
9020423
9021c) 18% W, 4% Ni, 1% V
9022d) 18% Cr, 4% Ni, 1% V
902310. Cubic boron nitride
9024a) Has a very high hardness which is comparable to that of diamond.
9025b) Has a hardness which is slightly more than that of HSS.
9026c) Is used for making cylinder blocks of aircraft engines.
9027d) Is used for making optical glasses.
9028MATERIALS ENGINEERING & TECHNOLOGY
90291. The number of atoms present in the unit cell of face centered cubic (FCC) structure is
9030a) 2
9031b) 4
9032c) 6
9033d) 8
90342. Which one of the following is the correct ascending order of packing density for the given crystal structures of metals?
9035a) Simple cubic – Face centred cubic – Body centred cubic
9036b) Body centred cubic - Simple cubic - Face centred cubic
9037c) Simple cubic - Body centred cubic - Face centred cubic
9038d) Face centred cubic - Body centred cubic - Simple cubic -
90393. The number of atoms present on (100) plane in the unit cell of face centered cubic (FCC) structure is:
9040424
9041a) 2
9042b) 3
9043c) 4
9044d) 6
90454. Which one of the following factors is more relevant to represent complete solubility of two metals in each other?
9046a) Chemical affinity
9047b) Valency factor
9048c) Crystal structure factor
9049d) Relative size factor
90505. Decreasing grain size in a polycrystalline material
9051a) increases yield strength and corrosion resistance.
9052b) decreases yield strength and corrosion resistance
9053c) decreases yield strength but increases corrosion resistance
9054d) increases yield strength but decreases corrosion resistance
90556. The reaction that yields two solid phases on cooling a single solid phase is called
9056a) eutectic
9057b) peritectoid
9058c) peritectic
9059d) eutectoid
90607. Phase formed of diffusionless reaction:
9061a) Coarse Pearlite
9062b) Fine Pearlite
9063425
9064c) Bainite
9065d) Martensite
90668. Pearlite phase in steel is made up of
9067a) alternate layers of martensite and cementite
9068b) alternate layers of ferrite and cementite
9069c) alternate layers of ferrite and martensite
9070d) alternate layers of bainite and cementite
90719. Which one of the following is not correct
9072a) Martensite has a BCC structure
9073b) Austenite has FCC structure
9074c) α-ferrite has BCC structure
9075d) alternate layers of bainite and cementite
907610. Frenkel and Schottky defects are:
9077a) dislocations in ionic crystals
9078b) grain boundaries in covalent crystals
9079c) point defects in ionic crystals
9080d) point defects in covalent crystals
908111. α-iron has BCC structure. In a unit cell of α-iron, the iron atoms occupy
9082a) 74% of volume of unit cell
9083b) 80% of volume of unit cell
9084c) 68% of volume of unit cell
9085d) 90% of volume of unit cell
9086426
908712. Consider the following temperature ranges: (a) Room temperature (b) 0 to 910 degree C (c) 910 degree C to 1400 degree C (d) 1400 degree C to below melting point
9088In which of the above temperature ranges ferrite with body centered cubic (BCC) structure is
9089indicated in the Fe-Fe3C phase diagram?
9090a) a, b, d
9091b) b, c, d
9092c) a, c
9093d) b, c
909413. A measure of Rockwell hardness is the
9095a) depth of penetration of indenter
9096b) surface area of indentation
9097c) projected area of indentation
9098d) height of rebound
909914. Consider the following statements about FCC and HCP crystal structure: (a) Both have same coordination number and atomic packing fraction, (b) Both represent closely packed crystal structures, (c) Both structures are generated by stacking of close packed plants on top of one another, but only the stacking sequence is different. Which of the statements given above are correct?
9100a) a, b
9101b) b, c
9102c) a, b, c
9103d) a, c
910415. Chemicals attack atoms within grain boundaries preferentially because they have
9105a) lower energy than those in the grains
9106b) higher energy than those in the grains
9107427
9108c) higher number of atoms than in the grains
9109d) lower number of atoms than in the grains
911016. What is the movement of block of atoms along certain crystallographic planes and directions, termed as?
9111a) Glide
9112b) Twinning
9113c) Slip
9114d) Jog
911517. The B.C.C. and H.C.P. metals undergo plastic deformation by:
9116a) Slip
9117b) Twinning
9118c) Edge dislocation
9119d) Twinning in combination with slip
912018. Consider the following statements about medium carbon steel: (a) It can be quench-hardened but not case-hardened, (b) It cannot be quench-hardened but case-hardening can be done,(c) It exhibits distinct yield point under tension test. Which of the following statements given above are correct?
9121a) a & b
9122b) b & c
9123c) a & c
9124d) a, b & c
912519. Which of the following factors influence in a plain carbon steel? (a) Percentage carbon, (b) Quenching media, (c) Work size.
9126Select the correct answer using the code given below:
9127a) a & b
9128428
9129b) a & c
9130c) b & c
9131d) a, b & c
913220. According to Gibbs' phase rule, the number of degrees of freedom of an eutectic point in a binary system is
9133a) 0
9134b) 1
9135c) 2
9136d) 3
913721. In a eutectic system, two elements are completely
9138a) insoluble in solid and liquid states
9139b) soluble in liquid state
9140c) soluble in solid state
9141d) insoluble in liquid state
914222. Eutectic reaction for iron-carbon system occurs at
9143a) 600°C
9144b) 723°C
9145c) 1150°C
9146d) 1493°C
914723. Increase of ferrite phase in steel increases:
9148a) Strength
9149b) Hardness
9150c) Ductility
9151429
9152d) Brittleness
915324. Pearlite consists of
9154a) 6.67% C and 93.33% ferrite
9155b) 13% Fe and 87% cementite
9156c) 13% C and 87% ferrite
9157d) 13% cementite and 87% ferrite
915825. Which one of the following sets of constituents is expected in equilibrium cooling of a hypereutectoid steel from austenitic state?
9159a) Ferrite and pearlite
9160b) Cementite and pearlite
9161c) Ferrite and bainite
9162d) Cementite and martensite
916326. Which one of the following sets of constituents is expected in equilibrium cooling of a hypoeutectoid steel from austenitic state?
9164a) Ferrite and pearlite
9165b) Cementite and pearlite
9166c) Ferrite and bainite
9167d) Cementite and martensite
916827. Martensite is a super-saturated solution of carbon in
9169a) alpha iron
9170b) beta iron
9171c) gamma iron
9172d) delta iron
9173430
917428. Nodular grey cast iron is obtained from the grey cast iron by adding a small amount of
9175a) Manganese
9176b) Phosphorus
9177c) Magnesium
9178d) Chromium
917929. An iron-carbon binary alloy has 0.5% C by weight. What is this alloy called?
9180a) Eutectoid alloy
9181b) Eutectic alloy
9182c) Hypo-eutectoid alloy
9183d) Hypereutectoid alloy
918430. The percentage of carbon in gray cast iron is in the range of
9185a) 0.25 to 0.75 percent
9186b) 1.25 to 1.75 percent
9187c) 3 to 4 percent
9188d) 8 to 10 percent
918931. 18/8 stainless steel contains
9190a) 18% stainless, 8% chromium
9191b) 18% chromium, 8% nickel
9192c) 18% tungsten, 8% nickel
9193d) 18% tungsten, 8% chromium
919432. TTT diagram indicates time and temperature transformation of
9195a) Cementite
9196b) Pearlite
9197431
9198c) Ferrite
9199d) Austenite
920033. The ductility of a material with work hardening
9201a) increases
9202b) decreases
9203c) remains unaffected
9204d) unpredictable
920534. Tempering is a process of annealing
9206a) martensite at low temperatures
9207b) martensite at higher temperatures
9208c) bainite at low temperatures
9209d) bainite at higher temperatures
921035. Austempering is employed to obtain:
9211a) 100% martensitic structure
9212b) 100% bainitic structure
9213c) 50% martensitic and 50% bainitic structure
9214d) 100% pearlitic structure
921536. Martempering is employed to obtain:
9216a) 100% martensitic structure
9217b) 100% bainitic structure
9218c) 50% martensitic and 50% bainitic structure
9219d) 100% pearlitic structure
9220432
922137. Tempering of quenched martensitic steel is necessary to improve the
9222a) hardness of the metal
9223b) surface texture or the metal
9224c) corrosion resistance of the metal
9225d) ductility or the metal
922638. On completion of heat treatment, the resulting structure will have retained Austenite if
9227a) rate of cooling is greater than the critical cooling rate
9228b) rate of cooling is less than the critical cooling rate
9229c) martensite formation starting temperature is above the room temperature
9230d) martensite formation finish temperature is below the room temperature
923139. The complete phase recrystallization and fine grain structure is obtained in casting, forging and rolled parts by:
9232a) Process annealing
9233b) Normalizing
9234c) Spheroidizing
9235d) Austenising
923640. Heating the hypo eutectoid steels to 30 degC above the upper critical temperature line, soaking at that temperature and then cooling slowly to room temperature to form a coarse pearlite and ferrite structure, is known as
9237a) Full Annealing
9238b) Process Annealing
9239c) Spherodizing
9240d) Normalizing
924141. Globular form of cementite in the structure of steel is obtained through
9242433
9243a) Normalizing
9244b) Malleabilising
9245c) Spheroidizing
9246d) Carbonizing
924742. During heat treatment of steel, the hardness of various structures in increasing order is
9248a) martensite, fine pearlite, coarse pearlite, spherodite
9249b) fine pearlite, coarse pearlite, spherodite, martensite
9250c) martensite, coarse pearlite, fine pearlite, spherodite
9251d) spherodite, coarse pearlite, fine pearlite, martensite
925243. In case carburising Carbon is introduced to form a high carbon layer at the surface. The carbon is introduce in the form of
9253a) graphite flakes
9254b) pearlite
9255c) cementite
9256d) free carbon
925744. Induction hardening is basically a
9258a) carburising process
9259b) surface hardening process
9260c) core-hardening process
9261d) none of the above
926245. Carburized machine components have high endurance limit because carburization
9263a) raises the yield point of the material
9264b) produces a better surface finish
9265434
9266c) introduces a compressive layer on the surface
9267d) suppresses any stress concentration produced in the component.
926846. Yield stress is
9269a) stress corresponding to proportional limit
9270b) stress causing materials to break
9271c) stress causing a specific permanent deformation usually 0.1% or 0.2%
9272d) not related with engineering
927347. Which one of the following is the correct definition of ultimate tensile strength, as derived from the results of a tensile test on a metal specimen:
9274a) the stress encountered when the stress strain curve transforms from elastic to plastic behavior
9275b) the maximum load divided by the final area of the specimen
9276c) the maximum load divided by the original area of the specimen
9277d) the stress observed when the specimen finally fails
927848. In brittle material, normally, fracture stress is:
9279a) higher than ultimate stress
9280b) lower than ultimate stress
9281c) equals with ultimate stress
9282d) none of the above
928349. With melting points given in brackets, tick the material which will creep significantly at 180 degC
9284a) Pb (327 degC)
9285b) Fe (1538 degC)
9286435
9287c) Cu (1084 degC)
9288d) W (3410 degC)
928950. The treatment in which the brittleness of martensite is reduced is called which one of the following
9290a) annealing
9291b) austenitizing
9292c) normalizing
9293d) tempering
929451. Plain carbon steels are designated in the AISI code system by which of the following:
9295a) 01XX
9296b) 10XX
9297c) 11XX
9298d) 12XX
929952. Glass products are based primarily on which one of the following minerals:
9300a) alumina
9301b) corundum
9302c) kaolinite
9303d) silica
930453. What are the materials which show direction dependent properties, called?
9305a) Homogeneous materials
9306b) Viscoelastic materials
9307c) Isotropic materials
9308d) Anisotropic materials
9309436
931054. Quartz is a
9311a) ferroelectric material
9312b) ferromagnetic material
9313c) piezoelectric material
9314d) diamagnetic material
931555. Which one of the following is true?
9316a) Structure of metallic materials consists of atoms having valence of 5, 6 or 7
9317b) Ceramic materials have long range electron matrix bond
9318c) Polymers are composed of long chain of repeating molecules
9319d) Ceramics are weaker than metals because of weak electrostatic bond
932056. Weldable type plastic(s) include (s)
9321a) thermosets alone
9322b) thermoplastics alone
9323c) both thermosets and thermoplastics
9324d) neither thermosets and thermoplast
932557. Which one among the following is the most effective strengthening mechanism of non-ferrous metal?
9326a) Solid solution hardening
9327b) Strain hardening
9328c) Grain size refinement
9329d) Precipitation hardening
933058. The Jominy end-quench test is designed to indicate which one of the following:
9331437
9332a) cooling rate
9333b) ductility
9334c) hardenability
9335d) hardness
933659. The correct order of coordination number in BCC, FCC and HCP unit cells is
9337a) 12, 8, 6
9338b) 8, 12, 12
9339c) 6, 8, 12
9340d) 12, 8, 24
934160. Magnesium crystallizes in HCP structure. If the lattice constant is 0.32 nm, the nearest neighbour distance in magnesium is
9342a) 0.64 nm
9343b) 0.32 nm
9344c) 0.16nm
9345d) 0.8 nm
934661. In Hume Rothery rules for extensive solid solubility, the atomic diameter of the solute and the solvent atoms should not differ by more than
9347a) 15 %
9348b) 50 %
9349c) 2 %
9350d) 0 %
935162. In a tensile test, necking starts at
9352a) Ultimate tensile stress
9353b) Lower yield stress
9354438
9355c) Upper yield stress
9356d) None of the above
935763. Which phenomenon is not used in the measurment of hardness?
9358a) Wear
9359b) Fracture
9360c) Scratch
9361d) Indentation
936264. Which hardness method can measure hardness of a grain?
9363a) Knoop
9364b) Brinel
9365c) Vicker
9366d) Rockwell
936765. The fatigue strength of mild steel is
9368a) equal to its yield strength
9369b) lower than its yield strength
9370c) equal to its tensile strength
9371d) lower than its tensile strength
937266. The reaction that on heating one solid phase yields another solid phase together with one liquid phase is termed
9373a) peritectic
9374b) peritectoid
9375c) eutectic
9376d) eutectoid
9377439
937867. Burger’s vector of an edge dislocation is
9379a) parallel to dislocation line
9380b) perpendicular to dislocation line
9381c) at any angle with dislocation line including 0 and 90°
9382d) none of the above
938368. Yield point in mild steel occurs because
9384a) carbon atom occupy the vacancy line just below the dislocation and anchor dislocation by reducing
9385its energy.
9386b) slip is promoted by carbon atoms to take place in several parallel plans simultaneously
9387c) carbon atoms form iron carbide with iron
9388d) none of the above
938969. The metals which do not form adherent oxide film on surface are
9390a) Gold and Silver
9391b) Iron and Steel
9392c) Copper and Aluminium
9393d) Nickel and Titanium
939470. The highest percentage of chromium that can be added to steel is usually
9395a) 25
9396b) 18
9397c) 15
9398d) Nickel and Titanium
9399440
940071. Whiskers are
9401a) very thin steel wires
9402b) very thin copper wires
9403c) very thin single crystals
9404d) none of the above
940572. Copper is ductile, because
9406a) it is a perfect crystal.
9407b) it contains a very high density of dislocations.
9408c) it has glassy structure.
9409d) the stress to move a dislocation in it is low.
941073. The ASTM grain size number of a material which has 64 grains per sq. in. at a magnification 50 X is about
9411a) 14
9412b) 7
9413c) 5
9414d) 6
941574. A silicate glass has a relatively low fracture strength, because
9416a) the Young's modulus of glass is low
9417b) the cracks propagate, before Griffith criterion is satisfiiied
9418c) plastic deformation during crack propagation causes fracture
9419d) the cracks are sharp and propagate as soon as Griffith condition is met
942075. Liberty ships in world war II failed by brittle fracture due to:
9421a) going above the ductile-brittle transition temperature
9422441
9423b) going below the ductile-brittle transition temperature
9424c) glass superstructure
9425d) defective reveting
942676. The matrix phase of fibrous composites may be
9427a) a metal only
9428b) a polymer only
9429c) a ceramic only
9430d) a metal, polymer, or ceramic
943177. A laminar composite is composed of
9432a) one-dimensional sheets or panels
9433b) two-dimensional sheets or panels
9434c) three-dimensional sheets or panels
9435d) none of the above
943678. Major load carrier in dispersion-strengthened composites
9437a) Matrix
9438b) Fiber
9439c) Both
9440d) Can’t define
944179. Following is not the 2-dimensional imperfection
9442a) Twin boundary
9443b) Dislocation
9444c) Surface
9445d) Grain boundary
9446442
944780. Thermodynamically stable defects
9448a) Point defects
9449b) Line defects
9450c) Surface defects
9451d) Volume defects
945281. Which of the following is false?
9453a) Line defects are thermodynamically stable
9454b) Dislocation can end inside a crystal without forming loop
9455c) ABC ABC ABC…is stacking sequence for HCP crystal
9456d) All
945782. Plastic deformation results from the following
9458a) Slip
9459b) Twinning
9460c) Both
9461d) None
946283. Minimum number of slip systems that must be operative during plastic deformation
9463a) 3
9464b) 4
9465c) 5
9466d) 6
946784. If ASTM grain size number is 1, approximate grain diameter (in mm)
9468a) 0.1
9469443
9470b) 0.2
9471c) 0.25
9472d) 10
947385. Usually materials with following crystal structure fail in ductile mode
9474a) FCC
9475b) BCC
9476c) HCP
9477d) None
947886. Brittle fracture is more dangerous than ductile fracture because
9479a) No warning sign
9480b) Crack propagates at very high speeds
9481c) No need for extra stress during crack propagation
9482d) All
948387. Not a characteristic property of ceramic material
9484a) high temperature stability
9485b) high mechanical strength
9486c) low elongation
9487d) low hardness
948888. Mechanical properties of fiber-reinforced composites depend on
9489a) Properties of constituents
9490b) Interface strength
9491c) Fiber length, orientation, and volume fraction
9492d) All the above
9493444
949489. Kevlar is commercial name for
9495a) Glass fibers
9496b) Carbon fibers
9497c) Aramid fibers
9498d) Cermets
949990. Which of the following material can elongate the most in room temperature?
9500a) Metal
9501b) Polymer
9502c) Ceramic
9503d) Composite
950491. Which one of the following is not the purpose of full annealing
9505a) refines grains
9506b) induces softness
9507c) removes strains and stresses
9508d) produces hardest material
950992. Miller indices of the diagonal plane of a cube are
9510a) (200)
9511b) (111)
9512c) (110)
9513d) (100)
951493. Find out the degree of freedom when BCC and FCC iron coexist in equilibrium.
9515a) 0
9516445
9517b) 1
9518c) 2
9519d) 3
952094. Which of the following statement is incorrect about duralumin?
9521a) It is prone to age hardening
9522b) It can be forged
9523c) It has good machining properties
9524d) It is lighter than pure aluminium
952595. Wood is a natural composite consisting of which of the following?
9526a) Lignin fibres in collagen matrix
9527b) Lignin fibres in apatite matrix
9528c) Cellulose fibres in apatite matrix
9529d) Cellulose fibres in lignin matrix
953096. Which one of the following processes or processing steps is not applicable in glassworking:
9531a) annealing
9532b) pressing
9533c) quenching
9534d) sintering
953597. Which one of the following processes for the new ceramic materials accomplishes shaping and sintering simultaneously:
9536a) doctor-blade process
9537b) freeze drying
9538c) hot pressing
9539446
9540d) injection molding
954198. Tensile strength of a mild steel specimen can be roughly predicted from following hardness test
9542a) Brinell
9543b) Rockwell
9544c) Vicker
9545d) none of the above
954699. Which one of the following elements is an austenite stabilizer?
9547a) Nickel
9548b) Chromium
9549c) Vanadium
9550d) Tungsten
9551100. To be considered corrosion resistant, steels have to include minimally:
9552a) 11 %
9553b) 18 %
9554c) 6 %
9555d) 3 %
95561. All are attributes of ceramics,except
9557a) covalent bond
9558b) low melting point
9559c) high stiffness
9560d) high hardness
9561447
95622. What class of material might be useful at temperatures 1100°C?
9563a) pure metals
9564b) polymer-polymer composites
9565c) ceramic-cermic composites
9566d) lead-tin metal alloy
95673. Steel is best characterized as a:
9568a) Al-Cu alloy, possibly with other alloying elements
9569b) Cu-Zn alloy
9570c) Fe-Ni alloy
9571d) Fe-C alloy, possibly with other alloying elements
95724. Malleable iron is made from which of the following irons
9573a) Pig iron
9574b) White cast iron
9575c) Gray cast iron
9576d) Wrought iron
95775. Which one of the following is not a synthetic abrasive material?
9578a) Silicon Carbide
9579b) Aluminium Oxide
9580c) Titanium Nitride
9581d) Cubic Boron Nitride
95826. Which one of the following is not a ceramic?
9583a) Alumina
9584448
9585b) Porcelain
9586c) Whisker
9587d) Pyrosil
95887. Carburized machine components have high endurance limit because carburization
9589a) Raises the yield point of the material
9590b) Produces a better surface finish
9591c) Introduces a compressive layer on the surface
9592d) Suppresses any stress’s, concentration produced in the component.
95938. The iron-carbon diagram and the TTT curves are determined under
9594a) Equilibrium and non-equilibrium conditions respectively
9595b) Non-equilibrium and equilibrium conditions respectively
9596c) Equilibrium conditions for both
9597d) Non-equilibrium conditions for both.
95989. TTT diagram indicates time and temperature transformation of
9599a) Cementite
9600b) Pearlite
9601c) Ferrite
9602d) Austenite
960310. The correct composition of austenitic stainless steel used for domestic utensils is
9604a) 0.08% C, 18% Cr, .8% Ni, 2% Mn, 1% Si
9605b) 0.08% C, 24% Cr, 12% Ni, 2% Mn, 1% Si
9606c) 0.15% C, 12% Cr, 0.5% Ni, 1% Mn, 1% Si
9607d) 0.30% C, 12% Cr, 0.4% Ni, 1% Mn, 1% Si
9608449
960911. Which of the following composites are 'dispersion-strengthened composites’?
9610a) Particulate composites
9611b) Laminar composites
9612c) Fiber reinforced composites
9613d) Short-fiber discontinuous composites
961412. Which one of the following materials is not a composite?
9615a) Wood
9616b) Concrete
9617c) Plywood
9618d) Sialon
961913. Which one of the following is true?
9620a) Structure of metallic materials consists of atoms having valence of 5, 6 or 7
9621b) Ceramic materials have long range electron matrix bond
9622c) Polymers are composed of long chain of repeating molecules
9623d) Ceramics are weaker than metals because of weak electrostatic bond
962414. For a ductile material, toughness is a measure of
9625a) resistance to scratching
9626b) ability to absorb energy up to fracture
9627c) ability to absorb energy till elastic limit
9628d) resistance to indentation
962915. Which of the following descriptions would not be applicable to ceramics?
9630a) Mixed ionic and covalent bonding
9631450
9632b) Brittle
9633c) Ductile
9634d) Structure comprising Metal cations with non-metallic anions
963516. One close packed direction in an FCC unit cell can be described as
9636a) [100]
9637b) [010]
9638c) [110]
9639d) [111]
964017. Epoxy is an example of a
9641a) metal
9642b) ceramic
9643c) thermoplastic polymer
9644d) thermoset polymer
964518. Which one of the following crystal structures has the fewest slip directions and therefore the metals with this structure are generally more difficult to deform at room temperature?
9646a) FCC
9647b) BCC
9648c) HCP
9649d) None
9650e) None
965119. Which of the following materials has the highest specific heat?
9652a) aluminum
9653b) concrete
9654451
9655c) polyethylene
9656d) water
965720. Of the following quenching media, which one produces the most rapid cooling rate?
9658a) air
9659b) brine
9660c) oil
9661d) pure water
966221. In precipitation hardening, the hardening and strengthening of the metal occurs in which one of the following steps (one answer only)?
9663a) aging
9664b) quenching
9665c) solution treatment
9666d) annealing
966722. A family of directions is represented by
9668a) (hkl)
9669b) <uvw>
9670c) {hkl}
9671d) [uvw]
967223. Which one of the following does NOT improve fatigue life of a steel component?
9673a) Nitriding
9674b) Decarburization
9675c) Improving surface finish
9676d) Shot-peening
9677452
967824. Binary phase diagrams of two component systems are usually
9679a) two dimensional plots of temperature and pressure.
9680b) two dimensional plots of temperature and composition.
9681c) two dimensional plots of pressure and composition.
9682d) two dimensional plots of pressure, temperature and composition.
968325. Solder is an alloy consisting of
9684a) tin, antimony, copper
9685b) tin and lead
9686c) lead and copper
9687d) lead and antimony
968826. Pure iron is the structure of
9689a) ferrite
9690b) pearlite
9691c) cementite
9692d) bainite
969327. Slow plastic deformation of metal under a constant stress is known as
9694a) Creep
9695b) fatigue
9696c) endurance
9697d) non plastic deformation
969828. The fraction of pearlite in a 0.55% C steel is
9699a) 0.55
9700453
9701b) 0.31
9702c) 0.69
9703d) 0
970429. Heat treatment that requires heating a part below A1 temperature, i.e. between 550°C and 650°C is called as
9705a) hardening
9706b) normalizing
9707c) process annealing
9708d) full annealing
970930. Which one of the following is not correct
9710a) Martensite has a BCC structure
9711b) Austenite has FCC structure
9712c) Martensite is a solid solution of carbon in BCC iron
9713d) The martensite which is formed during quenching is too brittle
971431. Decreasing grain size in a polycrystalline material
9715a) Increases yield strength and corrosion resistance
9716b) Decreases yield strength and corrosion resistance
9717c) Decreases yield strength but increases corrosion resistance
9718d) Increases yield strength but decreases corrosion resistance.
971932. When the temperature of a solid metal increases,
9720a) Strength of the metal decreases but ductility increases
9721b) Both strength and ductility of the metal decrease
9722c) Both strength and ductility of the metal increase
9723454
9724d) Strength of the metal increases but ductility decreases
972533. Which one of the following factors is more relevant to represent complete solubility of two metals in each other?
9726a) Chemical affinity
9727b) Valency factor
9728c) Crystal structure factor
9729d) Relative size factor
973034. Assertion (A): Elements are classified into metals and non-metals on the basis of their atomic weights.
9731Reason (R): The valence electron structures contribute to the primary bonding between the atoms to form aggregates.
9732a) Both A and R are true and R is the correct explanation of A
9733b) Both A and R are true but R is NOT the correct explanation of A
9734c) A is true but R is false
9735d) A is false but R is true
973635. Which of the following statement is true about brittle fracture?
9737a) High temperature and low strain rates favour brittle fracture
9738b) Many metal with HCP crystal structure commonly show brittle fracture
9739c) Brittle fracture is always preceded by noise
9740d) Cup and cone formation is characteristic for brittle materials
974136. Assertion (A): Cast iron is generally hard, brittle and wear resistant.
9742Reason (R): Cast iron contains more than 2% carbon and as such the percentage cementite in it is higher.
9743a) Both A and R are individually true and R is the correct explanation of A
9744455
9745b) Both A and R are individually true but R is not the correct explanation of A
9746c) A is true but R is false
9747d) A is false but R is true
974837. Assertion (A): The notch sensitivity of cast iron component is zero.
9749Reason (R): Cast iron does not have a yield point.
9750a) Both A and R are individually true and R is the correct explanation of A
9751b) Both A and R are individually true but R is not the correct explanation of A
9752c) A is true but R is false
9753d) A is false but R is true
975438. Addition of magnesium to cast iron increases its
9755a) Hardness
9756b) Ductility and strength in tension
9757c) Corrosion resistance
9758d) Creep strength
975939. Assertion (A): Machine tool beds are generally made of grey cast iron.
9760Reason (R): Cast iron possesses good self-lubricating properties.
9761a) Both A and R are individually true and R is the correct explanation of A
9762b) Both A and R are individually true but R is not the correct explanation of A
9763c) A is true but R is false
9764d) A is false but R is true
976540. Assertion (A): Austenitic stainless steel contains 18% chromium and 8% nickel. Since it retains its austenitic structure at room temperature, it is called austenitic stainless steel.
9766Reason (R): Chromium present in the steel improves its corrosion resistance by forming a thin film of chromium oxide on the surface.
9767456
9768a) Both A and R are individually true and R is the correct explanation of A
9769b) Both A and R are individually true but R is not the correct explanation of A
9770c) A is true but R is false
9771d) A is false but R is true
9772457
9773OPERATIONS RESEARCH
97741. Customers arrive at a ticket counter at a rate of 50 per hr and tickets are issued in the order of their arrival. The average time taken for issuing a ticket is 1 min. Assuming that customer arrivals form a Poisson process and service times are exponentially distributed, the average waiting time in queue in min is
9775a) 3
9776b) 4
9777c) 5
9778d) 6
97792. A linear programming problem is shown below.
9780Maximize 3x + 7y
9781Subject to 3x + 7y ≤ 10
97824x + 6y ≤ 8
9783x, y ≥ 0
9784It has
9785a) an unbounded objective function
9786b) exactly one optimal solution.
9787c) exactly two optimal solutions.
9788d) infinitely many optimal solutions.
97893. Cars arrive at a service station according to Poisson’s distribution with a mean rate of 5 per hour. The service time per car is exponential with a mean of 10 minutes. At steady state, the average waiting time in the queue is
9790a) 10 minutes
9791b) 20 minutes
9792c) 25 minutes
9793d) 50 minutes
9794458
97954. Little’s law is relationship between
9796a) stock level and lead time in an inventory system
9797b) waiting time and length of the queue in a queuing system
9798c) number of machines and job due dates in a scheduling problem
9799d) uncertainty in the activity time and project completion time
98005. Simplex method of solving linear programming problem uses
9801a) all the points in the feasible region
9802b) only the corner points of the feasible region
9803c) intermediate points within the infeasible region
9804d) only the interior points in the feasible region.
98056. The project activities, precedence relationships and durations are described in the table. The critical path of the project is
9806Activity Precedence Duration (in days)
9807P - 3
9808Q - 4
9809R P 5
9810S Q 5
9811T R,S 7
9812U R,S 5
9813V T 2
9814W U 10
9815a) P-R-T-V
9816b) Q-S-T-V
9817c) P-R-U-W
9818459
9819d) Q-S-U-W
98207. Four jobs are to be processed on a machine as per data listed in the table.
9821Job Processing time (in days) Due date
98221 4 6
98232 7 9
98243 2 19
98254 8 17
9826If the Earliest Due Date (EDD) rule is used to sequence the jobs, the number of jobs delayed is
9827a) 1
9828b) 2
9829c) 3
9830d) 4
98318. Consider the following Linear Programming Problem (LPP):
9832Maximize z = 3x + 2y
9833Subject to x ≤ 4
9834y ≤ 6
98353x + 2y ≤ 18
9836x ≥ 0, y ≥ 0
9837a) The LPP has a unique optimal solution
9838b) The LPP is infeasible
9839c) The LPP is unbounded
9840d) The LPP has multiple optimal solutions
9841460
98429. Jobs arrive at a facility at an average rate of 5 in an 8 hour shift. The arrival of the jobs follows Poisson distribution. The average service time of a job on the facility is 40 minutes. The service time follows exponential distribution. Idle time (in hours) at the facility per shift will be
9843a) 5/7
9844b) 14/3
9845c) 7/5
9846d) 10/3
984710. The total number of decision variables in the objective function of an assignment problem of size n × n (n jobs and n machines) is
9848a) n x n
9849b) 2n
9850c) 2n−1
9851d) n
9852OPERATIONS RESEARCH
98531. Linear programming is a tool most useful in-------
9854a) Production management
9855b) Project implementation
9856c) Reducing tax liability
9857d) Energy management
98582. The mathematical technique for finding the best use of limiteed resourcees in an optimum manner is called
9859a) Operations research
9860b) Linear programming
9861461
9862c) Network analysis
9863d) Queuing theory
98643. In order that linear programming techniques provide valid results, the
9865a) Relation between factors must be linear (positive)
9866b) Relation between factors must be linear (negative)
9867c) Relation between factors must be linear (Both positive and negative)
9868d) Only one factor should change at a time, others remaining consant
98694. The linear programming techniques can be applied successfully to industries like
9870a) Iron and steel
9871b) Food processing
9872c) Oil and chemical
9873d) All the options given
98745. The simplex method is the basic method for
9875a) Value analysis
9876b) Operation research
9877c) Linear programming
9878d) Model analysis
98796. Graphical method, simplex method and transportation method are concerned with
9880a) Value analysis
9881b) Linear programming
9882c) Break even analysis
9883d) Queuing theory
9884462
98857. In simplex method of linear programming, the objective row of the matrix consists of
9886a) Basic variables
9887b) Coefficient of the objective function, which is the profit contribution per unit of each of the products
9888c) Slack variables
9889d) None of the options given
98908. In linear programming shadow prices are
9891a) Cost of brought out items
9892b) Maximum cost per item
9893c) Vaalue assigned to one unit of capacity
9894d) Lowest sale prices
98959. In the graphical method of linear programming problem, the optimum solution would lie in the feasible polygon at
9896a) Its one corner
9897b) Its center
9898c) Middle of any side
9899d) None of the options given
990010. In the simplex method, the variables which have not been assigned the value zero, during an iteration, are called
9901a) Basic variable
9902b) Artificial variable
9903c) Actual variable
9904d) Non basic variable
9905463
990611. In the simplex method, the existence of more than one optimum solution is indicated, when
9907a) Values of the index row, Cj-Zj under one or more of the non-base decision variables is are zero
9908b) Sum of the values in the constant column (bi) are zero
9909c) All the replacement ratio, bi/ais (s is the key column) are negative
9910d) the values of index row, cj-zj, indicate optimality, with artificial variable in the base
991112. The values of base variable in the assignment model is
9912a) 2 or 4
9913b) 1 or 0
9914c) 1 or 2
9915d) 0 or 4
991613. The initial simplex table corresponds to what aspect of a graphical solution in a two variable maximization problem?
9917a) Feasible solution space
9918b) Point where the two constraint lines intesect
9919c) Intersection of X and Y axes
9920d) Intersection of the first constraint line with Y axis
992114. A basic feasible solution in simplex method is one, when all the
9922a) decision variables are in the base
9923b) decision variables and surplus variables are assigned zero values
9924c) base variables are non-negative
9925d) base variables satisfy the constraint equations
992615. Artificial variable is introduced, in the simplex method to
9927464
9928a) determine the initial basic feasible solution, when surplus variable is present
9929b) convert the inequation with the sign greater than or equal to, in the form of an equation
9930c) aply Big-M method for solution to linear programming problems
9931d) indicate the sensitivity of the surplus variable
993216. Limitations of linear prograamming models are based on criterio of
9933a) proportionality
9934b) additivity
9935c) divisibility
9936d) all the options given
993717. The artificial variables are made to leave the base and never to enter in the further iteration by the application of
9938a) Big M method
9939b) Two phase method
9940c) Simplex method
9941d) Big M method and Two phase method
994218. At the optimal solution
9943a) value of the objective is same for the optimal and dual
9944b) values of the decision variable (Wi) in the dual problem indicates the contribition per unit of the ith resource, to the value of the objective
9945c) Value of the objective is same for the optimal and dual and the values of the decision variable (Wi) in the dual problem indicates the contribition per unit of the ith resource, to the value of the objective
9946d) None of the options given
994719. If the primal contains 'n' decision variables and 'm' constraints, its dual would contain
9948465
9949a) 'n' decision variables and 'm' constraints
9950b) 'm' decision variables and 'n' constraints
9951c) 'm' decision variables and 'm' constraints
9952d) 'n' decision variables and 'n' constraints
995320. Dual of the dual is the
9954a) dual
9955b) primal
9956c) either dual or primal
9957d) neither dual or nor primal
995821. If all the variables are unrestricted in sign and in the normal canonical form, then its dual would have all the constraaints in the form of equations and the dual variable would be
9959a) negative
9960b) non-negative
9961c) positive
9962d) none of the options given
996322. The performance of a system, as expressed in the form of linear programming model can be improved by
9964a) increasing the activities contribution
9965b) increasing the availability of resources
9966c) reducing the activities consumption of resources
9967d) all the options given
996823. The optimality of a transportation problem is determined by the applicaation of
9969a) North west corner method
9970b) Least cost method
9971466
9972c) Vogel's approximation method
9973d) Row minima method
997424. In a transportation problem, there are four supply centers and five demand centers. The total quantity of supply available is greater than the total demand.The number of allocations, without degeneracy during an iteration is
9975a) 3
9976b) 6
9977c) 9
9978d) 0
997925. Fulkerson's rule is connected with
9980a) numbering of event in PERT/CPM
9981b) the simulation model
9982c) queuing theory
9983d) Game theory
998426. In a linear programming model, there are n variables and m constraints. The condition of degeneracy is that during an iteration, the total number of allocated base calls should be
9985a) equal to (m+n-1)
9986b) more than (m+n-1)
9987c) less than (m+n-1)
9988d) equal to (m+n)
998927. Optimality is reached when all index values are
9990a) zero
9991b) negative
9992c) positive
9993467
9994d) none of the options given
999528. In assignment model
9996a) degenearcy always present in all the problems
9997b) number of resources is equal to number of jobs
9998c) only one unit from the ith source can be assigned to any one of its destination
9999d) All the options given
1000029. In a n X n matrix of an assignment problem, the optimality is reached when the minimum number of straight line scoring all the zeros is
10001a) square of n
10002b) one divided by n
10003c) n
10004d) n+3
1000530. In a M/M/1 queue, with utilization factor of 0.5, the probability of only one person waiting in the queue is
10006a) 0
10007b) 1
10008c) 0.125
10009d) 1.25
1001031. The city corporation is having a computer to record birthes in a locality, where it is estimated that, on an average there is birth in every two hours. The probability that no-birth takes place in a day, in this locality will be
10011a) 0.000006
10012b) 0.00006
10013c) 0.0006
10014468
10015d) 0.006
1001632. In a M/M/1 queue, the service rate is
10017a) Poisson
10018b) Log normal
10019c) Linear
10020d) Non Linear
1002133. In a M/M/1 queue, the mean service rate as compared to mean arrival rate is
10022a) more
10023b) less
10024c) same
10025d) none of the options given
1002634. The ratio of mean arrival time to mean service time is found as 1.2. It indicates that the queue would
10027a) become explosive
10028b) not become explosive
10029c) uncertain
10030d) none of the options given
1003135. In a single channel que, if mean waiting time in the system is 50 mins, the mean waiting time in the queue is 30 min, then mean rate of service will be
10032a) 3/hour
10033b) 2/hour
10034c) 1/hour
10035d) 5/hour
10036469
1003736. The utilization factor of a break down maintenance system with a single crew is 80%. The expected number of machines down at any time will be
10038a) 1
10039b) 2
10040c) 4
10041d) 8
1004237. As the ratio of mean arrival to mean service rate is increased, it is likely that,
10043a) Customer move through the system in less time, because utilization is increased
10044b) Customers move through the system slowly
10045c) Utilization is decreased because of the added strain on the system
10046d) The average number in the system decreases
1004738. A single server tool crib, with poisson arrival and exponential service, has an utilization factor of 75%.Application of work study had doubled the mean service rate. The expected time a worker spend in the system is
10048a) decreased by 20%
10049b) increased by 20%
10050c) decreased by 80%
10051d) increased by 80%
1005239. Simulation is basically a technique which is used for
10053a) Optimization
10054b) Testing alternatives
10055c) Cost minimization
10056d) Computerization
1005740. Simulation technique is used
10058470
10059a) to analyze and evaluate a system performance
10060b) to accommodate a great degree of complexity
10061c) to determine the system outcome
10062d) all the options given
1006341. The Pseudo random number generated should produce the sequence which is
10064a) uniformly distributed
10065b) statistically independent
10066c) reproducible
10067d) all the options given
1006842. Method used to generate Pseudo-random numbers is
10069a) Mid-square method
10070b) Additive congruential method
10071c) Multiplicative congruential method
10072d) All the options given
1007343. If seed number = 3, a = 2, b = 3, m = 10, then period of cycling by congruential method will be
10074a) 1
10075b) 2
10076c) 4
10077d) 8
1007844. A set of two or more vertices which belong to the network and may represent event, place, stage or a storage point is called
10079a) node
10080b) vertice
10081471
10082c) points
10083d) all the options given
1008445. For any network, value of the maximum flow from the source to sink is equal to the capacity of
10085a) Maximal cut
10086b) minimal cut
10087c) Both Maximal cut and minimal cut
10088d) none of the options given
1008946. A collection of oriented branches such that every oriented path from source to sink contains at least one branch in it, is
10090a) a cut in a network
10091b) capacity of thee cut
10092c) minimal cut
10093d) none of the options given
1009447. In a flow network, arcs A and B only are directly connected with the source and arcs P, Q, R are directly connected with the sink. The capacities of the arcs A, B, P, Q, R are as 70, 50, 30, 40, and 20 respectively. The maximum flow through the network cannot exceed
10095a) 30
10096b) 50
10097c) 70
10098d) 90
1009948. The target date of completion of a project is the length of the critical path. The earliest occurance of the events of the tail node (i) and head node (j) of an activity, i-j, in the critical path are 10 days and 15 days respectively. The free float of this activity is
10100a) 5 days
10101472
10102b) 0 days
10103c) 2.5 days
10104d) 2 days, if its activity durations time is 3 days.
1010549. The time which results in the least possible direct cost of an activity is called
10106a) Normal time
10107b) slow time
10108c) crash time
10109d) standard time
1011050. In the PERT network, distribution of the project completion time is assumed to follow
10111a) Beta distribution
10112b) Poisson distribution
10113c) Normal distribution
10114d) Binomial distribution
1011551. The estimated duration of times for an activity, in the PERT network under the worst and best environment are as 9 and 3 days. The variance of this activity is
10116a) 6 days
10117b) 1 day
10118c) 2 days
10119d) 9 days
1012052. CPM is
10121a) time oriented technique
10122b) activity oriented technique
10123c) event oriented technique
10124473
10125d) work oriented technique
1012653. PERT and CPM are
10127a) decision making techniques
10128b) techniques to determine project status
10129c) aids to the decision maker
10130d) all the options given
1013154. A delay in the activity which is on the non-critical path
10132a) would not increase the completion time of the project
10133b) would increase project completion time, if the amount of delay is greater than free slack
10134c) increase the project cpmpletion time, if amount of delay exceeds total slack
10135d) would increase project completion time
1013655. A PERT activity has an optimistic time of three days, pessimistic time of 15 days and expected time is 7 days. The most likely time of the activity is
10137a) 5 days
10138b) 6 days
10139c) 7 days
10140d) 9 days
1014156. In the PERT network, duration of activities only are considered so as to follow
10142a) Normal distribution
10143b) Beta distribution
10144c) Linear distribution
10145d) Gamma distribution
10146474
1014757. In the PERT network, thee project completion time is considered to follow
10148a) Normal distribution
10149b) Beta distribution
10150c) Linear distribution
10151d) Gamma distribution
1015258. In PERT network, Beta distribution is assumed because
10153a) It is continuous
10154b) It is unimodal
10155c) There are two non-negative intercepts in the abscissa with b>a
10156d) all the options given
1015759. The most likely time is 'mode' of
10158a) Normal distribution
10159b) Beta distribution
10160c) Bionomial distribution
10161d) Gamma distribution
1016260. While crashing an activity in the critical path, the project cost would
10163a) increase and the indirect cost would decrease
10164b) decrease and the indirect cost would decrease
10165c) increase and the indirect cost would increase
10166d) decrease and the indirect cost would decrease
1016761. Problems to relating to situations in which queue is formed is covered by
10168a) PERT/CPM
10169b) Waiting line theory
10170475
10171c) Game theory
10172d) LPP
1017362. Which of the following is not an assumption of M/M/1:FCFS/∞/∞ model?
10174a) Queue discipline is first come first served
10175b) The calling population is finite
10176c) There is more than one channel
10177d) The mean arrival rate is less than the mean service rate for each channel
1017863. At a certain petrol pump customers arrive according to a poisson distribution with an average time of 5 minutes between arrivals. The service time is exponentially distributes with mean time 2 min. Service is first come first served. What is the probability of no units in the queue?
10179a) 4/3
10180b) 3/5
10181c) 2/3
10182d) 3/2
1018364. Which of the following replacement policy is used for replacement of items that fail suddenly?
10184a) Individual replacement policy
10185b) Group replacement policy
10186c) Both Individual and Group replacement policy
10187d) None of the options given
1018865. Customer arrival before a saving bank window follows poisson distribution with average 12 customers per hour. The service time follows exponential distribution with average service time 4 minutes. Assuming M/M/1 model, what is the fraction of time the service is busy?
10189a) 80%
10190476
10191b) 75%
10192c) 125%
10193d) 90%
1019466. Re-order level is
10195a) Safety stock
10196b) EOQ
10197c) Consumption during lead time
10198d) None of the options given
1019967. Shortage cost is
10200a) Inventory holding cost
10201b) Procurement price
10202c) Penalty cost
10203d) Transportation cost
1020468. The main objective of inventory control is
10205a) To keep inactive item at maximum level
10206b) To maximize inventory holding cost
10207c) To maintain investment in inventory at lowest level
10208d) To maintain inventory at zero level
1020969. Which of the following method is used to solve sequencing problem?
10210a) MODI method
10211b) Hungarian method
10212c) Johnson’s Algorithm
10213d) Simplex method
10214477
1021570. Which of the following one is correct in relation to Sequencing Problems?
10216a) Minimization total transportation cost
10217b) Minimization of total elapsed time
10218c) Minimization of total idle time of machines
10219d) Both minimization of total elapsed time and minimization of total idle time of machines
1022071. Which of the following one is not correct in relation to game theory?
10221a) Saddle point is identified as that element where the minimax and maximin strategies of the
10222players intersect.
10223b) Game value is the expected loss to a player if he and his opponent use their best strategies.
10224c) In game theory, best strategies are determined on the basis of minimax and maximin criterion of optimality.
10225d) Dominance method consists of eliminating certain strategies whose removal will not affect the final solution.
1022672. Which of the following is always true about a critical activity?
10227a) LS = EF
10228b) LF = LS
10229c) ES = LS
10230d) EF = ES
1023173. The critical path
10232a) Is any path that goes from the starting node to the completion node
10233b) Is a combination of all paths
10234c) Is the shortest path
10235d) Is the longest path
10236478
1023774. Which of these is not correct?
10238a) PERT is probabilistic in nature
10239b) CPM is deterministic in nature
10240c) CPM is event oriented
10241d) CPM and PERT use similar terminology but were developed independently
1024275. Mark the wrong statement
10243a) All activities on a critical path are critical activities
10244b) A project network may have one, or more critical paths
10245c) A delay in critical activity surely delays the completion of project
10246d) Each critical activity has identical earliest and the latest start times
1024776. Which of the following is not correct in respect of PERT calculations?
10248a) Expected time of an activity is a weighted average of three times estimates, a, m, and b with respective weights of 1, 4, and 1.
10249b) The completion time of an activity is assumed to follow normal distribution
10250c) The standard deviation of activity completion time is one-sixth of the excess of pessimistic over optimistic time
10251d) The sum total of variances of critical activity times gives the variance of the overall project completion time
1025277. In the simplex method, variables with non-zero values are called----
10253a) Non-basic variables
10254b) Basic solutions
10255c) Slack variables
10256d) Basic variables
1025778. Which of the following one is used in assigning crews to commercial airline flights?
10258479
10259a) Linear programming Problem
10260b) Assignment problem
10261c) Transportation Problem
10262d) Sequencing Problem
1026379. In LPP having only greater than or equal to constraints the initial basic feasible was provided by using
10264a) Slack variables
10265b) Surplus variables
10266c) Artificial variables
10267d) Both Surplus variables & Artificial variables
1026880. The technique of LPP is could be applied if the objective function is
10269a) Non linear in nature
10270b) Linear in nature
10271c) Curvilinear in nature
10272d) Quadratic in nature
1027381. A basic feasible solution in transportation problem with ‘m’ sources and ‘n’ destinations have non zero basic variable is less than m + n - 1
10274a) Optimum
10275b) Degenerate
10276c) In feasible
10277d) Non-degenerate
1027882. In any Linear programming problem having two variables x1 and x2
10279a) x1 should be more than zero, x2 can be less than zero
10280b) x2 should be more than zero and x1 equal to zero
10281480
10282c) x1 and x2 should be greater to or equal to zero
10283d) x1 and x2 should be less than or equal to zero
1028483. Which of the following one is a degenerate form of the transportation problem?
10285a) Linear programming Problem
10286b) Assignment problem
10287c) Transportation Problem
10288d) Sequencing Problem
1028984. Independent float occurs when all the
10290a) earliest activities are done late
10291b) later activities are done early
10292c) early activities are finished within time
10293d) Both earliest activities are done late and later activities are done early
1029485. PERT and CPM are
10295a) techniques to determine project status
10296b) decision making techniques
10297c) aids to determine the cost implications of project
10298d) None of the options given
1029986. critical activiites are those for which
10300a) float = 0
10301b) float =1
10302c) float < 1
10303d) float >1
10304481
1030587. An acievement of one more activiities in a project is called
10306a) event
10307b) result
10308c) outcome
10309d) none of the options given
1031088. A job requiring time and resources for its completion is an
10311a) activity
10312b) event
10313c) both activity and event
10314d) none of the options given
10315OPERATIONS RESEARCH
103161. Who coined the term Operations Research?
10317a) J.F. McCloskey
10318b) F.N. Trefethen
10319c) P.F. Adams
10320d) Both J.F. McCloskey and F.N. Trefethen
103212. The term Operations Research was coined in the year ‐‐‐‐‐‐‐‐‐‐‐‐‐‐
10322a) 1950
10323b) 1940
10324c) 1978
10325d) 1960
103263. This innovative science of Operations Research was discovered during ‐‐‐‐‐‐‐‐‐‐‐‐‐
10327482
10328a) Civil War
10329b) World War I
10330c) World War II
10331d) Industrial Revolution
103324. Who defined Operations Research as scientific method of providing executive departments with a quantitative basis for decisions regarding the operations under their control?
10333a) Morse and Kimball (1946)
10334b) P.M.S. Blackett (1948)
10335c) E.L. Arnoff and M.J. Netzorg
10336d) None of the options given
103375. Operations Research has the characteristics the it is done by a team of ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
10338a) Scientists
10339b) Mathematicians
10340c) Academics
10341d) All the options given
103426. Operations Research simply helps in improving the ‐‐‐‐‐‐‐‐‐‐‐‐‐‐ of the solution but does not result in a perfect solution.
10343a) Quality
10344b) Clarity
10345c) Look
10346d) None of the options given
103477. Operations Research involves ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ attack of complex problems to arrive at the optimum solution
10348a) Scientific
10349483
10350b) Systematic
10351c) Both Scientific and Systematic
10352d) Statistical
103538. Operations Research uses models built by quantitative measurement of the variables concerning a given problem and also derives a solution from the model using ‐‐‐‐‐‐‐‐‐‐‐‐‐ of the diversified solution techniques
10354a) Two or more
10355b) One or more
10356c) Three or more
10357d) Only One
103589. A solution may be extracted from a model either by
10359a) Conducting experiments on it
10360b) Mathematical analysis
10361c) Both Conducting experiments on it and Mathematical analysis
10362d) Diversified Techniques
1036310. What have been constructed for Operations Research problems and methods for solving the models that are available in many cases?
10364a) Scientific Models
10365b) Algorithms
10366c) Mathematical Models
10367d) None of the options given
1036811. Which technique is used in finding a solution for optimizing a given objective, such as profit maximization or cost minimization under certain constraints?
10369a) Quailing Theory
10370484
10371b) Waiting Line
10372c) Both Quailing Theory and Waiting Line
10373d) Linear Programming
1037412. What can be defined as a useful idle resource which has economic value eg; raw materials, spare parts, finished items, etc?
10375a) Inventory Control
10376b) Inventory
10377c) Inventory Planning
10378d) None of the options given
1037913. Key concept under which technique are network of events and activities , resource allocation, time and cost considerations, network paths and critical paths ?
10380a) Game Theory
10381b) Network Analysis
10382c) Decision Theory
10383d) None of the options given
1038414. Which technique is used to imitate an operation prior to actual performance ?
10385a) Simulation
10386b) Integrated Production Models
10387c) Inventory Control
10388d) Game Theory
1038915. What is concerned with the prediction of replacement costs and determination of the most economic replacement policy ?
10390a) Search Theory
10391b) Theory of replacement
10392485
10393c) Probabilistic Programming
10394d) None of the options given
1039516. What refers to Linear Programming that includes an evaluation of relative risks and uncertainties in various alternatives of choice for management decisions ?
10396a) Probabilistic Programming
10397b) Stochastic Programming
10398c) Both Probabilistic Programming and Stochastic Programming
10399d) Linear Programming
1040017. What enables us to determine the earliest and the latest times for each of the events and activities and thereby helps in the identification of the critical path?
10401a) Programme Evaluation
10402b) Review Technique (PERT)
10403c) Both Programme Evaluation and Review Technique (PERT)
10404d) Deployment of resources
1040518. Linear Programming technique is used to allocate scarce resources in an optimum manner in problems of ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ ?
10406a) Schedule
10407b) Product Mix
10408c) Both Schedule and Product Mix
10409d) Servicing Cost
1041019. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ models involves the allocation of resources to activities in such a manner that some measure of effectiveness is optimized.
10411a) Sequencing
10412b) Allocation Models
10413486
10414c) Queuing Theory
10415d) Decision Theory
1041620. In ‐‐‐‐‐‐‐‐‐‐‐ models, everything is defined and the results are certain
10417a) Deterministic Models
10418b) Probabilistic Models
10419c) Both Deterministic Models and Probabilistic Models
10420d) None of the options given
1042121. The operations Research technique, specially used to determine the optimum strategy is
10422a) Decision Theory
10423b) Simulation
10424c) Game Theory
10425d) None of the options given
1042622. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ are called mathematical models
10427a) Iconic Models
10428b) Analogue Models
10429c) Symbolic Models
10430d) None of the options given
1043123. Replacement Model is a ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ model
10432a) Static Models
10433b) Dynamic Models
10434c) Both Static Models and Dynamic Models
10435d) None of the options given
10436487
1043724. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐ may be defined as a method of determining an optimum programme inter dependent activities in view of available resources
10438a) Goal Programming
10439b) Linear Programming
10440c) Decision Making
10441d) None of the options given
1044225. The objective functions and constraints are linear relationship between ‐‐‐‐‐‐‐‐‐‐‐‐‐
10443a) Variables
10444b) Constraints
10445c) Functions
10446d) All of the options given
1044726. Assignment problem helps to find a maximum weight identical in nature in a weighted ‐‐‐‐‐‐‐‐‐‐‐‐
10448a) Tripartite graph
10449b) Bipartite graph
10450c) Partite graph
10451d) None of the options given
1045227. The solution need not be in ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ numbers
10453a) Prime Number
10454b) Whole Number
10455c) Complex Number
10456d) None of the options given
1045728. Graphic method can be applied to solve a LPP when there are only ‐‐‐‐‐‐‐‐‐‐‐‐‐ variable
10458a) One
10459488
10460b) More than One
10461c) Two
10462d) Three
1046329. The variables whose coefficient vectors are unit vectors are called ‐‐‐‐‐‐‐‐‐‐‐‐
10464a) Unit Variables
10465b) Basic Variables
10466c) Non basic Variables
10467d) None of the options given
1046830. A minimization problem can be converted into a maximization problem by changing the sign of coefficients in the ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
10469a) Constraints
10470b) Objective Functions
10471c) Both Constraints and Objective Functions
10472d) None of the options given
1047331. In maximization cases , ‐‐‐‐‐‐‐‐‐‐‐‐‐ are assigned to the artificial variables as their coefficients in the objective function
10474a) +m
10475b) –m
10476c) 0
10477d) None of the options given
1047832. For maximization in TP , the objective is to maximize the total ‐‐‐‐‐‐‐‐‐‐
10479a) Solution
10480b) Profit Matrix
10481c) Profit
10482489
10483d) None of the options given
1048433. If the total supply is less than the total demand, a dummy source (row) is included in the cost matrix with ‐‐‐‐‐‐‐‐‐‐‐‐‐
10485a) Dummy Demand
10486b) Dummy Supply
10487c) Zero Cost
10488d) Both Dummy Demand and Dummy Supply
1048934. In a Transportagtion Problem, the number of non‐negative independent allocation is ‐‐‐‐‐‐‐‐‐‐‐‐ than m+n‐1.
10490a) a) Equivalent
10491b) b) Greater
10492c) c) Less
10493d) d) None of the options given
1049435. Once the initial basic feasible solution has been computed , what is the next step in the problem
10495a) VAM
10496b) Modified distribution method
10497c) Optimality test
10498d) None of the options given
1049936. State which of the two statements is correct
10500(i) the cells in the transportation table can be classified in to occupied cells and unoccupied cells
10501(ii) optimal solution is a feasible solution (not necessarily basic ) which maximizes the total cost
10502490
10503a) both (i) and (ii) are correct
10504b) Two only
10505c) One only
10506d) Both (i) and (ii) are incorrect
1050737. Optimal solution is a feasible solution (not necessarily basic ) which minimizes the ‐‐‐‐‐‐‐‐‐‐
10508a) Time taken
10509b) Partial cost
10510c) Total cost
10511d) None of the options given
1051238. Optimality conditions are expressed as ‐‐‐‐‐‐‐‐‐‐‐‐‐ incase all non‐basic cells?
10513a) Negligent costs
10514b) Advanced costs
10515c) Reduced costs
10516d) None of the options given
1051739. A path formed by allowing horizontal and vertical lines and the entire corner cells of which are occupied is called a ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
10518a) Occupied path
10519b) Open path
10520c) Closed path
10521d) None of the options given
1052240. Any set of non‐negative allocations (Xij>0) which satisfies the raw and column sum (rim requirement )is called a ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
10523491
10524a) Linear programming
10525b) Basic feasible solution
10526c) Feasible solution
10527d) None of the options given
1052841. Which of the following is a valid objective function for a linear programming problem?
10529a) Max 5xy
10530b) Min 4x + 3y + (2/3)z
10531c) Max 5xy + 6y
10532d) Min (x1 + x2)/x3
1053342. To find the optimal solution to a linear programming problem using the graphical method
10534a) find the feasible point that is the farthest away from the origin.
10535b) find the feasible point that is at the highest location.
10536c) find the feasible point that is closest to the origin.
10537d) None of the options given.
10538492
10539Strength of Materials
105401. Two identical circular rods of same diameter and same length are subjected to same magnitude of axial tensile force. One of the rods is made out of mild steel having the modulus of elasticity of 206 GPa. The other rod is made out of cast iron having the modulus of elasticity of 100 GPa. Assume both the materials to be homogeneous and isotropic and the axial force causes the same amount of uniform stress in both the rods. The stresses developed are within the proportional limit of the respective materials. Which of the following observations is correct?
10541a) Both rods elongate by the same amount
10542b) Mild steel rod elongates more than the cast iron rod
10543c) Cast iron rod elongates more than the mild steel rod
10544d) As the stresses are equal strains are also equal in both the rods
105452. A long thin walled cylindrical shell, closed at both ends, is subjected to an internal pressure. The ratio of the hoop stress (circumferential stress) to longitudinal stress developed in the shell is
10546a) 0.5
10547b) 1
10548c) 2
10549d) 4
105503. A simply supported beam PQ is loaded by a clockwise moment of 1kN-m at the mid-span of the beam. The reaction forces at supports P and Q respectively are
10551a) 1kN downward, 1kN upward
10552b) 0.5kN upward, 0.5kN downward
10553c) 0.5kN downward, 0.5kN upward
10554d) 1kN upward, 1kN upward
10555493
105564. A column has a rectangular cross-section of 10mm x 20mm and a length of 1m. The slenderness ratio of the column is close to
10557a) 200
10558b) 346
10559c) 477
10560d) 1000
105615. A thin cylinder of inner radius 500mm and thickness 10mm is subjected to an internal pressure of 5MPa. The average circumferential (hoop) stress in MPa is
10562a) 250
10563b) 500
10564c) 750
10565d) 1000
105666. A rod of length L having uniform cross-sectional area A is subjected to a tensile force P. If the Young’s modulus of the material varies linearly from E1 to E2 (Given that; E1>E2) along the length of the rod, the normal stress
10567developed at the section-SS is
10568a) P/A
10569b) [P(E1-E2)]/[A(E1+E2)]
10570c) PE2/AE1
10571d) PE1/AE2
105727. The threaded bolts A and B of same material and length are subjected to identical tensile load. If the elastic strain energy stored in bolt A is 4 times that of the bolt B and the mean diameter of bolt A is 12mm, the mean diameter of bolt B in mm is
10573a) 16
10574b) 24
10575c) 36
10576494
10577d) 48
105788. If the principal stresses in a plane stress problem, are 100MPa, and 40MPa, the magnitude of the maximum shear stress (in MPa) will be
10579a) 10 MPa
10580b) 20 MPa
10581c) 30 MPa
10582d) 40 MPa
105839. Plane stress for a point in a body are 10 MPa and 100 MPA. The design is to be done on the basis of the maximum shear stress theory for yielding. Then, yielding will just begin if the designer chooses a ductile material whose yield strength is
10584a) 45 MPa
10585b) 50 MPa
10586c) 55 MPa
10587d) 0
1058810. The Young's modulus of elasticity of a material is 2.5 times its modulus of rigidity. The Posson's ratio for the material will be:
10589a) 0.25
10590b) 0.5
10591c) 0.75
10592d) 1
10593STRENGTH OF MATERIALS
10594495
105951. A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the
10596a) axis of load
10597b) perpendicular to the axis of load
10598c) maximum moment of inertia
10599d) minimum moment of inertia
106002. The neutral axis of the cross-section a beam is that axis at which the bending stress is
10601a) zero
10602b) minimum
10603c) maximum
10604d) infinity
106053. Euler's formula holds good only for
10606a) short columns
10607b) long columns
10608c) both short and long columns
10609d) weak columns
106104. The object of caulking in a riveted joint is to make the joint
10611a) free from corrosion
10612b) stronger in tension
10613c) free from stresses
10614d) leak-proof
106155. A steel bar of 5 mm is heated from 15° C to 40° C and it is free to expand. The bar Will induce
10616a) no stress
10617496
10618b) shear stress
10619c) tensile stress
10620d) compressive stress
106216. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress will be
10622a) 400 MPa
10623b) 500 MPa
10624c) 900 MPa
10625d) 1400 MPa
106267. Two shafts 'A' and 'B' transmit the same power. The speed of shaft 'A' is 250 r.p.m. and that of shaft 'B' is 300 r.p.m. The shaft 'B' has the greater diameter.
10627a) True
10628b) False
10629c) Can't be dermined
10630d) None
106318. A thick cylindrical shell having R and r as outer and inner radii, is subjected to an internal pressure (p). The maximum tangential stress at the inner surface of the shell is
10632a) [p(R^2 + r^2)]/[R^2 - r^2]
10633b) [p(R^2 - r^2)]/[R^2 + r^2]
10634c) [2pr^2]/[R^2 - r^2]
10635d) [R^2 - r^2]/[2pr^2]
106369. The stress induced in a body, when suddenly loaded, is __________ the stress induced when the same load is applied gradually.
10637a) equal to
10638497
10639b) one-half
10640c) twice
10641d) four times
1064210. Compression members always tend to buckle in the direction of the
10643a) axis of load
10644b) perpendicular to the axis of load
10645c) minimum cross section
10646d) least radius of gyration
1064711. If the slenderness ratio for a column is 100, then it is said to be a __________ column.
10648a) long
10649b) medium
10650c) short
10651d) all
1065212. The maximum diameter of the hole that can be punched from a plate of maximum shear stress 1/4th of its maximum crushing stress of punch, is equal to (where t = Thickness of the plate)
10653a) t
10654b) 2t
10655c) 4t
10656d) 8t
1065713. Two closely coiled helical springs 'A' and 'B' are equal in all respects but the number of turns of spring 'A' is half that of spring 'B' The ratio of deflections in spring 'A' to spring 'B' is
10658a) 2
10659b) 1/2
10660498
10661c) 1/4
10662d) 1/8
1066314. A thin cylindrical shell of diameter (d) and thickness (t) is subjected to an internal pressure (p). The ratio of longitudinal strain to volumetric strain is
10664a) (m-1)/(2m-1)
10665b) (2m-1)/(m-1)
10666c) (m-2)/(3m-4)
10667d) (m-2)/(5m-4)
1066815. In the torsion equation, the term J/R is called
10669a) shear modulus
10670b) section modulus
10671c) polar modulus
10672d) Young's modulus
1067316. Strain resetters are used to
10674a) measure shear strain
10675b) measure linear strain
10676c) measure volumetric strain
10677d) relative strain
1067817. When a rectangular cantilever beam is loaded transversely, the maximum compressive stress is developed on the
10679a) top layer
10680b) bottom layer
10681c) middle layer
10682d) every cross-section
10683499
1068418. The point of contraflexure is a point where
10685a) shear force changes sign
10686b) bending moment changes sign
10687c) shear force is maximum
10688d) bending moment is maximum
1068919. The simply supported beam 'A' of length l carries a central point load W. Another beam 'B' is loaded with a uniformly distributed load such that the total load on the beam is W. The ratio of maximum deflections between beams A and B is
10690a) 5/8
10691b) 8/5
10692c) 5/4
10693d) 4/5
1069420. The maximum stress produced in a bar of tapering section is at
10695a) smaller end
10696b) larger end
10697c) middle
10698d) anywhere
1069921. The energy stored in a body when strained within elastic limit is known as
10700a) resilience
10701b) proof resilience
10702c) strain energy
10703d) impact energy
10704500
1070522. In compression test, the fracture in cast iron specimen would occur along
10706a) the axis of load
10707b) an oblique plane
10708c) at right angles to the axis of specimen
10709d) would not occur
1071023. The bending stress in a beam is __________ section modulus.
10711a) directly proportional to
10712b) not directly proportional to
10713c) inversely proportional to
10714d) not inversely proportional to
1071524. When shear force at a point is zero, then bending moment is __________ at that point.
10716a) zero
10717b) minimum
10718c) maximum
10719d) infinity
1072025. When a unconstrained bar is cooled to - 5°C, it will develop
10721a) no stress
10722b) shear stress
10723c) tensile stress
10724d) compressive stress
1072526. A composite shaft consisting of two stepped portions having spring constants k1 and k2 is held between two rigid supports at the ends. Its equivalent spring constant is
10726a) (k1+k2)/2
10727501
10728b) (k1+k2)/(k1*k2)
10729c) (k1*k2)/(k1+k2)
10730d) k1*k2
1073127. Resilience is the
10732a) energy stored in a body when strained within elastic limits
10733b) energy stored in a body when strained upto the breaking of the specimen
10734c) maximum strain energy which can be stored in a body
10735d) none of the above
1073628. If the depth is kept constant for a beam of uniform strength, then its width will vary in proportional to (where M = Bending moment)
10737a) M^(1/2)
10738b) M
10739c) M^2
10740d) M^3
1074129. A concentrated load is one which
10742a) acts at a point on a beam
10743b) spreads non-uniformly over the whole length of a beam
10744c) spreads uniformly over the whole length of a beam
10745d) varies uniformly over the whole length of a beam
1074630. If the tearing efficiency of a riveted joint is 50%, then ratio of rivet hole diameter to the pitch of rivets is
10747a) 0.2
10748b) 0.3
10749c) 0.5
10750502
10751d) 0.8
1075231. The rectangular beam 'A' has length l, width b and depth d. Another beam 'B' has the same length and depth but width is double that of 'A'. The elastic strength of beam 'B' will be __________ as compared to beam A.
10753a) same
10754b) double
10755c) four times
10756d) six times
1075732. In a simple bending of beams, the stress in the beam varies
10758a) linearly
10759b) parabolically
10760c) hyperbolically
10761d) elliptically
1076233. The stress at which the extension of the material takes place more quickly as compared to the increase in load, is called
10763a) elastic limit
10764b) yield point
10765c) ultimate point
10766d) breaking point
1076734. When two main plates are kept in alignment butting each other and riveted with cover plate on both sides of the main plates with two rows of rivets in each main plate, the joint is known as __________ double cover butt joint.
10768a) single riveted
10769b) double riveted
10770503
10771c) quarter riveted
10772d) four riveted
1077335. Whenever a material is loaded within elastic limit, stress is __________ strain
10774a) equal to
10775b) directly proportional to
10776c) inversely proportional to
10777d) none
1077836. Which of the following statement is correct?
10779a) The energy stored in a body, when strained within elastic limit is known as strain energy.
10780b) The maximum strain energy which can be stored in a body is termed as proof resilience.
10781c) The proof resilience per unit volume of a material is known as modulus of resilience.
10782d) all of the above
1078337. The maximum tangential stress in a thick cylindrical shell is always __________ the internal pressure acting on the shell.
10784a) equal to
10785b) less than
10786c) greater than
10787d) none
1078838. Principle plane is a plane on which the shear stress is
10789a) maximum
10790b) minimum
10791c) zero
10792d) any value
10793504
1079439. When a thin cylindrical shell is subjected to an internal pressure, there will be
10795a) a decrease in diameter and length of the shell
10796b) an increase in diameter and decrease in length of the shell
10797c) a decrease in diameter and increase in length of the shell
10798d) an increase in diameter and length of the shell
1079940. A welded joint as compared to a riveted joint has __________ strength.
10800a) more
10801b) less
10802c) same
10803d) can't say
1080441. The point of contraflexure occurs in
10805a) cantilever beams
10806b) simply supported beams
10807c) overhanging beams
10808d) fixed beams
1080942. For a 25 mm hole drilled in plates, the diameter of rivet shank should be
10810a) 23mm
10811b) 25mm
10812c) 25.01mm
10813d) 26mm
1081443. A beam of uniform strength has
10815a) same cross-section throughout the beam
10816505
10817b) same bending stress at every section
10818c) same bending moment at every section
10819d) same shear stress at every section
1082044. In a simple bending theory, one of the assumption is that the material of the beam is isotropic. This assumption means that the
10821a) normal stress remains constant in all directions
10822b) normal stress varies linearly in the material
10823c) elastic constants are same in all the directions
10824d) elastic constants varies linearly in the material
1082545. The extremeties of any diameter on Mohr's circle represent
10826a) principal stresses
10827b) normal stresses on planes at 45°
10828c) shear stresses on planes at 45°
10829d) normal and shear stresses on a plane
1083046. The Poisson's ratio for cast iron varies from
10831a) 0.23 to 0.27
10832b) 0.25 to 0.33
10833c) 0.31 to 0.34
10834d) 0.32 to 0.42
1083547. The Rankine's theory for active earth pressure is based on the assumption that
10836a) the retained material is homogeneous and cohesionless
10837b) the frictional resistance between the retaining wall and the retained material is neglected
10838c) the failure of the retained material takes place along a plane called rupture plane
10839506
10840d) all of the above
1084148. The strain energy stored in a spring, when subjected to maximum load, without suffering permanent distortion, is known as
10842a) impact energy
10843b) proof resilience
10844c) proof stress
10845d) modulus of resilience
1084649. The resultant stress on an inclined plane which is inclined at an angle θ to the normal cross-section of a body which is subjected to a direct tensile stress (σ) in one plane, is
10847a) σ sin θ
10848b) σ cos θ
10849c) σ sin 2θ
10850d) σ cos 2θ
1085150. The ratio of change in volume to the original volume is called
10852a) linear strain
10853b) lateral strain
10854c) volumetric strain
10855d) Poisson's ratio
1085651. In a beam where shear force changes sign, the bending moment will be
10857a) zero
10858b) minimum
10859c) maximum
10860d) infinity
10861507
1086252. The ductility of a material __________ with the increase in percentage reduction in area of a specimen under tensile test.
10863a) increases
10864b) decreases
10865c) remains same
10866d) can't be determined
1086753. The rectangular beam 'A' has length l, width b and depth d. Another beam 'B' has the same length and width but depth is double that of 'A'. The elastic strength of beam B will be __________ as compared to beam A.
10868a) same
10869b) double
10870c) four times
10871d) six times
1087254. When a closely-coiled helical spring is subjected to an axial load, it is said to be under
10873a) bending
10874b) shear
10875c) torsion
10876d) crushing
1087755. According to Euler's column theory, the crippling load for a column of length (l) with one end fixed and the other end free is __________ the crippling load for a similar column hinged at both the ends.
10878a) equal to
10879b) less than
10880c) more than
10881d) half
10882508
1088356. If percentage reduction in area of a certain specimen made of material 'A' under tensile test is 60% and the percentage reduction in area of a specimen with same dimensions made of material 'B' is 40%, then
10884a) the material A is more ductile than material B
10885b) the material B is more ductile than material A
10886c) the ductility of material A and B is equal
10887d) the material A is brittle and material B is ductile
1088857. The shear force diagram for a simply supported beam carrying a uniformly distributed load of w per unit length, consists of
10889a) one right angled triangle
10890b) two right angled triangles
10891c) one equilateral triangle
10892d) two equilateral triangles
1089358. A body is subjected to two normal stresses 20 kN/m^2 (tensile) and 10 kN/m^2 (compressive) acting perpendicular to each other. The maximum shear stress is
10894a) 5 kN/m^2
10895b) 10 kN/m^2
10896c) 15 kN/m^2
10897d) 20 kN/m^2
1089859. When a simply supported beam is loaded at its mid point, the maximum compressive stress shall develop at
10899a) bottom fibrer
10900b) top fibre
10901c) neutral axis
10902d) centre of gravity
10903509
1090460. The elongation of a conical bar under its own weight is __________ that of prismatic bar of the same length.
10905a) equal to
10906b) half
10907c) one-third
10908d) two-third
1090961. When the shear force diagram is a parabolic curve between two points, it indicates that there is a
10910a) point load at the two points
10911b) no loading between the two points
10912c) uniformly distributed load between the two points
10913d) uniformly varying load between the two points
1091462. The slenderness ratio is the ratio of
10915a) area of column to least radius of gyration.
10916b) length of column to least radius of gyration.
10917c) least radius of gyration to area of column.
10918d) least radius of gyration to length of column.
1091963. When two shafts of same length, one of which is hollow, transmit equal torques and have equal maximum stress, then they should have equal
10920a) polar moment of inertia
10921b) polar modulus
10922c) diameter
10923d) angle of twist
10924510
1092564. According to Euler's column theory, the crippling load for a column of length (l) fixed at both ends is __________ the crippling load for a similar column hinged at both ends.
10926a) equal to
10927b) two times
10928c) four times
10929d) eight times
1093065. The shear force and bending moment are zero at the free end of a cantilever beam, if it carries a
10931a) point load at the free end
10932b) point load at the middle of its length
10933c) uniformly distributed load over the whole length
10934d) none of the above
1093566. A rod is enclosed centrally in a tube and the assembly is tightened by rigid washers. If the assembly is subjected to a compressive load, then
10936a) rod is under compression
10937b) tube is under compression
10938c) both rod and tube are under compression
10939d) tube is under tension and rod is under compression
1094067. A bar of length L metres extends by l mm under a tensile force of P. The strain produced in the bar is
10941a) 1/L
10942b) 0.1 l/L
10943c) 0.01 l/L
10944d) 0.001 l/L
10945511
1094668. A shaft revolving at ω rad / s transmits torque (T) in N-m. The power developed is
10947a) T.ω watts
10948b) 2 π Tω watts
10949c) 2 π Tω/75 watts
10950d) 2 π Tω/4500 watts
1095169. The unit of modulus of elasticity is same as those of
10952a) stress, strain and pressure
10953b) stress, force and modulus of rigidity
10954c) strain, force and pressure
10955d) stress, pressure and modulus of rigidity
1095670. When a bar of length l, width b and thickness t is subjected to a pull of P, its
10957a) length, width and thickness increases
10958b) length, width and thickness decreases
10959c) length increases, width and thickness decreases
10960d) length decreases, width and thickness increases
1096171. A column with maximum equivalent length has
10962a) both ends hinged
10963b) length, width and thickness decreases
10964c) length increases, width and thickness decreases
10965d) length decreases, width and thickness increases
1096672. A column of length (L) with both ends fixed may be considered as equivalent to a column of length __________ with both ends hinged.
10967a) L/8
10968512
10969b) L/4
10970c) L/2
10971d) L
1097273. The product of the tangential force acting on the shaft and its distance from the axis of the shaft (i.e. radius of shaft) is known as
10973a) bending moment
10974b) twisting moment
10975c) torsional rigidity
10976d) flexural rigidity
1097774. When a body is subjected to a direct tensile stress (σ) in one plane, the maximum shear stress is __________ the maximum normal stress.
10978a) equal to
10979b) one-half
10980c) two-third
10981d) twice
1098275. A simply supported beam 'A' of length l, breadth b and depth d carries a central load W. Another beam 'B' of the same dimensions carries a central load equal to 2 W. The deflection of beam 'B' will be __________ as that of beam 'A'.
10983a) one-fourth
10984b) one-half
10985c) double
10986d) four times
1098776. Which of the following statement is correct?
10988a) A continuous beam has only two supports at the ends.
10989513
10990b) A uniformly distributed load spreads uniformly over the whole length of a beam.
10991c) The bending moment is maximum where shear force is maximum.
10992d) The maximum bending moment of a simply supported beam of length l with a central point load W is WL/8.
1099377. The ratio of the largest load in a test to the original cross-sectional area of the test piece is called
10994a) elastic limit
10995b) yield stress
10996c) ultimate stress
10997d) breaking stress
1099878. According to Euler's column theory, the crippling load of a column is given by p = π^2 EI/CL^2. In the Euler's formula, the value of C for a column with one end fixed and the other end free, is
10999a) 1/2
11000b) 1
11001c) 2
11002d) 4
1100379. Which of the following statement is wrong?
11004a) In the theory of simple bending, the assumption is that the plane sections before bending remains plane after bending.
11005b) In a beam subjected to bending moment, the strain is directly proportional to the distance from the neutral axis.
11006c) At the neutral axis of a beam, the bending stress is maximum.
11007d) The bending stress in a beam is inversely proportional to the section modulus.
1100880. A beam of T-section is subjected to a shear force of F. The maximum shear force will occur at the
11009514
11010a) top of the section
11011b) bottom of the section
11012c) neutral axis of the section
11013d) junction of web and flange
1101481. Two bars of different materials and same size are subjected to the same tensile force. If the bars have unit elongation in the ratio of 2:5, then the ratio of modulus of elasticity of the two materials will be
11015a) 2:5
11016b) 5:2
11017c) 4:3
11018d) 3:4
1101982. A beam of uniform strength may be obtained by
11020a) keeping the width uniform and varying the depth
11021b) keeping the depth uniform and varying the width
11022c) varying the width and depth both
11023d) any one of the above
1102483. The springs in brakes and clutches are used to
11025a) to apply forces
11026b) to measure forces
11027c) to store strain energy
11028d) to absorb shocks
1102984. The maximum deflection of a fixed beam (Length = L) carrying a central point load lies at
11030a) fixed ends
11031515
11032b) L/2 of beam
11033c) L/3 from fixed ends
11034d) none of these
1103585. Which of the following statement is correct?
11036a) The stress is the pressure per unit area.
11037b) The strain is expressed in mm.
11038c) Hook's law holds good upto the breaking point.
11039d) Stress is directly proportional to strain within propertional limit.
1104086. A bolt is made to pass through a tube and both of them are tightly fitted with the help of washers and nuts. If the nut is tightened, then
11041a) bolt arid tube are under tension
11042b) bolt and tube are under compression
11043c) bolt is under compression and tube is under tension
11044d) bolt is Under tension and tube is under compression
1104587. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The minimum normal stress will be
11046a) 400 MPa
11047b) 500 MPa
11048c) 900 MPa
11049d) 1400 MPa
1105088. The shear force diagram fora cantilever beam of length l and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is a
11051a) horizontal straight line
11052516
11053b) vertical straight line
11054c) inclined line
11055d) parabolic curve
1105689. The thermal or temperature stress is a function of
11057a) increase in temperature
11058b) modulus of elasticity
11059c) coefficient of linear expansion
11060d) all of these
1106190. When a column is subjected to an eccentric load, the stress induced in the column will be
11062a) direct stress only
11063b) bending stress only
11064c) shear stress only
11065d) direct and bending stress both
1106691. When a shaft is subjected to a twisting moment, every cross-section of the shaft will be under
11067a) tensile stress
11068b) compressive stress
11069c) shear stress
11070d) bending stress
1107192. A column is said to be a short column, when
11072a) its length is very small
11073b) its cross-sectional area is small
11074c) the ratio of its length to the least radhis of gyration is less than 80.
11075517
11076d) the ratio of its length to the least radius of gyration is more than 80.
1107793. In a thick cylindrical shell subjected to an internal pressure (p), the radial stress across the thickness of the cylinder is
11078a) maximum at the outer surface and minimum at the inner surface
11079b) maximum at the inner surface and minimum at the outer surface
11080c) maximum at the outer surface and zero at the inner surface
11081d) maximum at the inner surface and zero at the outer surface
1108294. Two closely-coiled helical springs 'A' and 'B' of the same matenal, same number of turns and made from same wire are subjected to an axial load W. The mean diameter of spring 'A' is double the mean diameter of spring 'B'. The ratio of deflections in spring 'B' to spring 'A' will be
11083a) 1/8
11084b) 1/4
11085c) 2
11086d) 4
1108795. Two shafts 'A' and 'B' have the same material. The shaft 'A' is solid of diameter 100 mm. The shaft 'B' is hollow with outer diameter 100 mm and inner diameter 50 mm. The torque transmitted by shaft 'B' is __________ as that of shaft 'A'.
11088a) 1/6
11089b) 1/8
11090c) 1/4
11091d) 15/16
1109296. In a thick cylindrical shell subjected to an internal pressure (p), the maximum radial stress at the inner surface of the shell is
11093a) zero
11094b) p (tensile)
11095518
11096c) -p (compressive)
11097d) 2p (tensile)
1109897. A column that fails due to direct stress, is called
11099a) short column
11100b) long column
11101c) weak column
11102d) medium column
1110398. A body is subjected to a direct tensile stress of 300 MPa in one plane accompanied by a simple shear stress of 200 MPa. The maximum shear stress will be
11104a) -100 MPa
11105b) 250 MPa
11106c) 300 MPa
11107d) 400 MPa
1110899. For long columns, thevalue of buckling load is __________ crushing load.
11109a) equal to
11110b) less than
11111c) more than
111121. The stress induced in a body, when suddenly loaded, is _________ the stress induced when the same load is applied gradually.
11113a) Equal to
11114b) One-half
11115519
11116c) Twice
11117d) Four times
111182. If Th is the torque resisting capacity of a hollow shaft and Ts is that of a solid shaft, of the same material, length and weight. Then,
11119a) Th > Ts
11120b) Th < Ts
11121c) Th = Ts
11122d) Th/Ts = 0.5
111233. A hollow shaft of same cross-section area as compared to a solid shaft transmit
11124a) Same torque
11125b) Less torque
11126c) More torque
11127d) Unpredictable
111284. The product of Young's modulus (E) and moment of inertia (I) is known as
11129a) Modulus of rigidity
11130b) Bulk modulus
11131c) Flexural rigidity
11132d) Torsional rigidity
111335. The intensity of stress which causes unit strain is called
11134a) Unit mass
11135b) Modulus of rigidity
11136c) Bulk modulus
11137d) Modulus of Elasticity
11138520
111396. A vertical column has two moments of inertia (i.e. Ixx and Iyy ). The column will tend to buckle in the direction of the
11140a) Axis of load
11141b) Perpendicular to the axis of load
11142c) Maximum moment of inertia
11143d) Minimum moment of inertia
111447. Two closely coiled helical springs 'A' and 'B' are equal in all respects but the number of turns of spring 'A' is half that of spring 'B' The ratio of deflections in spring 'A' to spring 'B' is
11145a) 1/8
11146b) 1/4
11147c) 1/2
11148d) 2
111498. A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The minimum normal stress will be
11150a) 400 MPa
11151b) 500 MPa
11152c) 900 MPa
11153d) 1400 MPa
111549. A coil is cut into two halves, the stiffness of cut coil will be
11155a) Same
11156b) Double
11157c) Half
11158d) Thrice
11159521
1116010. The bending stress in a beam is _________ section modulus.
11161a) Inversely proportional to two times
11162b) Directly proportional to
11163c) Inversely proportional to
11164d) Equal to
1116511. In order to know whether a column is long or short, we must know its
11166a) Ultimate shear stress of the column
11167b) Factor of safety
11168c) Torque resisting capacity
11169d) Slenderness ratio
1117012. Modulus of rigidity is defined as the ratio of
11171a) Longitudinal stress to longitudinal strain
11172b) Volumetric stress to volumetric strain
11173c) Lateral stress to Lateral strain
11174d) Shear stress to shear strain
1117513. The ratio of lateral strain to the linear strain within elastic limit is known as
11176a) Young's modulus
11177b) Bulk modulus
11178c) Modulus of rigidity
11179d) Poisson's ratio
1118014. The shear force diagram for a simply supported beam carrying a uniformly distributed load of w per unit length, consists of
11181522
11182a) One right angled triangle
11183b) Two right angled triangles
11184c) One equilateral triangle
11185d) Two equilateral triangle
1118615. Which of the following statement is correct?
11187a) The stress is the pressure per unit area
11188b) The strain is expressed in mm
11189c) Hook's law holds good up to the breaking point
11190d) Stress is directly proportional to strain within elastic limit
1119116. The value of shear stress which is induced in the shaft due to the applied couple varies
11192a) From maximum at the center to zero at the circumference
11193b) From zero at the center to maximum at the circumference
11194c) From maximum at the center to minimum at the circumference
11195d) From minimum at the center to maximum at the circumference
1119617. A column is said to be a short column, when
11197a) Its length is very small
11198b) Its cross-sectional area is small
11199c) The ratio of its length to the least radius of gyration is less than 80
11200d) The ratio of its length to the least radius of gyration is more than 80
1120118. If a material expands freely due to heating it will develop
11202a) Thermal stresses
11203b) Tensile stress
11204c) Bending
11205523
11206d) No stress
1120719. The shear force diagram of a cantilever beam of length ‘l’ and carrying a uniformly distributed load of w per unit length will be
11208a) A right angled triangle
11209b) An isosceles triangle
11210c) An equilateral triangle
11211d) A rectangle
1121220. When a bar is subjected to a change of temperature and its deformation is prevented, the stress induced in the bar is
11213a) Tensile stress
11214b) Compressive stress
11215c) Shear stress
11216d) Thermal stress
1121721. The bending equation is
11218a) T/J = τ/R = Cθ/l
11219b) M/I = σ/y = E/R
11220c) M/R = T/J = Cθ/l
11221d) T/l= τ/J = R/Cθ
1122222. When the shear force diagram is a parabolic curve between two points, it indicates that there is a
11223a) Point load at the two points
11224b) No loading between the two points
11225c) Uniformly distributed load between the two points
11226d) Uniformly varying load between the two points
11227524
1122823. Which of the following statement is wrong?
11229a) The deformation of the bar per unit length in the direction of the force is called linear strain.
11230b) The Poisson's ratio is the ratio of lateral strain to the linear strain.
11231c) The ratio of change in volume to the original volume is called volumetric strain.
11232d) The bulk modulus is the ratio of linear stress to the linear strain.
1123324. A pressure vessel is said to be a thick shell, when
11234a) It is made of thick sheets
11235b) The internal pressure is very high
11236c) The ratio of wall thickness of the vessel to its diameter is less than 1/10.
11237d) The ratio of wall thickness of the vessel to its diameter is greater than 1/10.
1123825. The deformation of a bar under its own weight compared to the deformation of same body subjected to a direct load equal to weight of the body is
11239a) Same
11240b) Double
11241c) Half
11242d) Four times
1124326. Which of the following statement is correct?
11244a) The energy stored in a body, when strained within elastic limit is known as strain energy.
11245b) The maximum strain energy which can be stored in a body is termed as proof resilience.
11246c) The proof resilience per unit volume of a material is known as modulus of resilience.
11247d) All of the above
1124827. Longitudinal stress in a thin cylinder is
11249525
11250a) Equal to the hoop stress
11251b) Twice the hoop stress
11252c) Half of the hoop stress
11253d) One fourth of hoop stress
1125428. A beam of uniform strength may be obtained by
11255a) Keeping the width uniform and varying the depth
11256b) Keeping the depth uniform and varying the width
11257c) Varying the width and depth both
11258d) Any one of the above
1125929. Which of the following has no unit?
11260a) Kinematic viscosity
11261b) Surface tension
11262c) Bulk modulus
11263d) Strain
1126430. Two closely-coiled helical springs 'A' and 'B' of the same material, same number of turns and made from same wire are subjected to an axial load W. The mean diameter of spring 'A' is double the mean diameter of spring 'B'. The ratio of deflections in spring 'B' to spring 'A' will be
11265a) 1/8
11266b) 1/4
11267c) 2
11268d) 4
1126931. The force acting along the circumference will cause stress in the walls in a direction normal to the longitudinal axis of cylinder; This stress is called
11270526
11271a) Longitudinal stress
11272b) Hoop stress
11273c) Yield stress
11274d) Ultimate stress
1127532. The change in length due to a tensile or compressive force acting on a body is given by (where P = Tensile or compressive force acting on the body, L = Original length of the body, A = Cross-sectional area of the body, and E = Young's modulus for the material of the body)
11276a) PLA/E
11277b) PL/AE
11278c) E/PLA
11279d) AE/PL
1128033. The hoop stress in a riveted cylindrical shell of diameter (d), thickness (t) and subjected to an internal pressure (p) is (where η = Efficiency of the riveted joint)
11281a) pd/η × t
11282b) pd/η × 2t
11283c) pd/η × 4t
11284d) pd/η × 8t
1128534. A thin spherical shell of diameter (d) and thickness (t) is subjected to an internal pressure (p). The stress in the shell material is
11286a) pd/t
11287b) pd/2t
11288c) pd/4t
11289d) pd/8t
11290527
1129135. The rectangular beam 'A' has length l, width b and depth d. Another beam 'B' has the same length and width but depth is double that of 'A'. The elastic strength of beam B will be __________ as compared to beam A.
11292a) Same
11293b) Double
11294c) Four times
11295d) Six times
1129636. The shear force diagram for a cantilever beam of length l and carrying a gradually varying load from zero at free end and w per unit length at the fixed end is a
11297a) Horizontal straight line
11298b) Vertical straight line
11299c) Inclined line
11300d) Parabolic curve
1130137. In a tensile test, when the material is stressed beyond elastic limit, the tensile strain __________ as compared to the stress.
11302a) Decreases slowly
11303b) Increases slowly
11304c) Decreases more quickly
11305d) Increases more quickly
1130638. The shear force of a cantilever beam of length l carrying a uniformly distributed load of w per unit length is _________ at the free end.
11307a) Zero
11308b) wl/4
11309c) wl/2
11310d) wl
11311528
1131239. When a cantilever beam is loaded at its free end, the maximum compressive stress shall develop at
11313a) Bottom fibre
11314b) Top fibre
11315c) Neutral axis
11316d) Center of gravity
1131740. The assumption made in the theory of the reinforced cement concrete beam is that
11318a) All the tensile stresses are taken up by the steel reinforcement only
11319b) There is a sufficient bond between steel and concrete
11320c) The steel and concrete are stressed within its elastic limit
11321d) All of the above
11322529
11323Thermal Engineering Systems
113241. The enthalphies at the beginning of compression, at the end of compression and at the end of the condensation are 185 kJ/kg, 210 kJ/kg and 85 kJ/kg respectively. The COP of the vapour compression refrigeration is
11325a) 0.25
11326b) 5.4
11327c) 4
11328d) 1.35
113292. A two satge compressor takes in air at 1.1. bar and discharges at 20 bar. for minimum compression work, the intermediate pressure is
11330a) 10.55 bar
11331b) 7.33 bar
11332c) 5.5 bar
11333d) 4.7 bar
113343. Air ( Cp = 1.0 kJ/kg ratio of specific heat = 1.4) enter a compressor at a temperature of 27 deg.C. The compressor ratio is 4. Asuuming an mechanical efficiency of 80%, the compressor work required in kJ/kg is
11335a) 160
11336b) 172
11337c) 182
11338d) 225
113394. The latent heat load in an auditoriam is 25% of sensible heat load. The value of sensible heat factor(SHF) is equal to
11340a) 0.25
11341b) 0.5
11342530
11343c) 0.8
11344d) 1.0
113455. A reversible heat engine receives 2 kJ of heat from a reservoir at 1000 K and a certain amount of
11346heat from a reservoir at 800 K. It rejects 1 kJ of heat to a reservoir at 400 K. The net work output (in kJ) of the cycle is
11347a) 0.8
11348b) 1.0
11349c) 1.4
11350d) 2.0
113516. On a mollier chart, the free expansion from high pressure to low pressure is expressed by
11352a) Horizontal straight line
11353b) vertical straight line
11354c) curved line
11355d) all the answers
113567. In a variable speed SI engine, the maximum torque will occur at maximum
11357a) speed
11358b) brake power
11359c) indicated power
11360d) volumetric efficiency
113618. The spark advance is usually specified in terms of
11362a) engine spped in rev/sec
11363b) time in seconds
11364c) degree of crank rotation
11365531
11366d) piston displacement from TDC
113679. The centrifugical advance mechanism is located in the
11368a) engine crankshft
11369b) engine flywheel
11370c) distributor
11371d) induction coil
1137210. The another name of humidity ratio of psychrometric property is _____________
11373a) specific humidity
11374b) degree of saturation
11375c) relative humidity
11376d) all the answers
11377532
11378THERMAL ENGINEERING SYSTEMS
113791. The thermal efficiency of a standard Otto cycle for a compression ratio of 5.5 will be
11380a) 25%
11381b) 50%
11382c) 75%
11383d) 100%
113842. The working cycle in case of four stroke engine is completed in following number of revolutions of crankshaft
11385a) 1/2
11386b) 1
11387c) 2
11388d) 4
113893. Supercharging is the process of
11390a) supplying the intake of an engine with air at a density greater than the density of the surrounding atmosphere
11391b) providing forced cooling air
11392c) Injecting excess fuel for raising more load
11393d) supplying compressed air to remove combustion products fully
113944. The ratio of indicated thermal efficiency to the corresponding air standard cycle efficiency is called
11395a) net efficiency
11396b) efficiency ratio
11397c) relative efficiency
11398d) overall efficiency
11399533
114005. The air standard efficiency of an Otto cycle compared to diesel cycle for the given compression ratio is
11401a) same
11402b) less
11403c) more
11404d) more or less depending on power rating
114056. If the intake air temperature of I.C. engine increases, its efficiency will
11406a) increase
11407b) decrease
11408c) remain same
11409d) unpredictable
114107. If the compression ratio of an engine working on Otto cycle is increased from 5 to 7, the %age increase in efficiency will be
11411a) 2%
11412b) 4%
11413c) 8%
11414d) 14%
114158. Combustion in compression ignition engines is
11416a) homogeneous
11417b) heterogeneous
11418c) homogeneous and hetrogeneous
11419d) laminar
114209. The fuel in diesel engine is normally injected at pressure of
11421534
11422a) 5-10 bar
11423b) 20-25 bar
11424c) 60-70 bar
11425d) 150-300 bar
1142610. The specific fuel consumption per kW hour for diesel engine is approximately
11427a) 0.15 kg
11428b) 0.2 kg
11429c) 0.25 kg
11430d) 0.3 kg
1143111. The inlet value of a four stroke cycle I.C engine remains open for nearly
11432a) 180°
11433b) 125°
11434c) 235°
11435d) 200°
1143612. Which of the following is not an internal combustion engine
11437a) 2-stroke petrol engine
11438b) gas turbine
11439c) diesel engine
11440d) steam turbine.
1144113. Pick up the false statement
11442a) Thermal efficiency of diesel engine is about 34%
11443b) Theoretically correct mixture of air an petrol is approximately 15 : 1
11444c) High speed compression igntion engines operate on dual combustion cycle
11445535
11446d) S.I. engines are quality-governed engines
1144714. The output of a diesel engine can be increased without increasing the engine revolution or size in following way
11448a) feeding more fuel
11449b) increasing flywheel size
11450c) heating incoming air
11451d) supercharging
1145215. The air-fuel ratio of the conventional petrol engine is controlled by
11453a) fuel pump
11454b) governor
11455c) injector
11456d) carburettor
1145716. Diesel fuel, compared to petrol is
11458a) less difficult to ignite
11459b) just about the same difficult to ignite
11460c) more difficult to ignite
11461d) highly ignitable
1146217. The cam shaft of a four stroke I.C. engine running at 1500 rpm will run at
11463a) 1500 rpm
11464b) 750 rpm
11465c) 3000 rpm
11466d) any value independent of engine speed
11467536
1146818. The specific fuel consumption of a petrol engine compared to diesel engine of same brake power is
11469a) same
11470b) more
11471c) less
11472d) less or more depending on operating conditions
1147319. The mean effective pressure obtained from engine indicator indicates the
11474a) maximum pressure developed
11475b) minimum pressure
11476c) average pressure
11477d) instantaneous pressure at any instant
1147820. Air fuel ratio for idling speed of a petrol engine is approximately
11479a) 1 : 1
11480b) 8:1
11481c) 15 : 1
11482d) 20 : 1.
1148321. For maximum power generation, the air fuel ratio for a petrol engine for vehicles, is of the order of
11484a) 9 : 1
11485b) 12 : 1
11486c) 15 : 1
11487d) 18 : 1
1148822. The knock in diesel engine occurs due to
11489a) instantaneous and rapid burning of the first part of the charge
11490537
11491b) instantaneous auto iginition of last part of charge
11492c) reduction of delay period
11493d) all the options
1149423. Which is more viscous lube oil
11495a) SAE 40
11496b) SAE 50
11497c) SAE 80.
11498d) SAE 70
1149924. Ignition quailty of petrol is expressed by
11500a) octane number
11501b) cetane number
11502c) calorific value
11503d) distillation temperature
1150425. Iso-octane
11505a) has octane number of 0
11506b) has octane number of 50
11507c) has octane number of 100
11508d) is an index of detonation quality
1150926. Cetane number is determined by comparing the performance of diesel oil with the following hydrocarbons
11510a) cetane
11511b) mixture of cetane and alphamethyl napthalene
11512c) ethylene dibromide
11513538
11514d) mixture of cetane with tetra-ethyl lead
1151527. In order to prevent knock in the S.I. engines, the charge away from the spark plug should have
11516a) low temperature
11517b) long ignition delay
11518c) rich mixture
11519d) all the options
1152028. To reduce the possibility of knock in the C.I. engines, the first elements of fuel and air should have
11521a) high temperature
11522b) high density
11523c) short delay
11524d) all the options
1152529. The detonation tendency in petrol engines for specified conditions of fuel rating, compression ratio, speed etc. can be controlled by having
11526a) smaller cylinder bore
11527b) bigger cylinder bore
11528c) medium cylinder bare
11529d) cylinder bore could be anything as it does not control detonation
1153030. The knocking in diesel engines for given fuel, will be
11531a) enhanced by increasing compression ratio
11532b) enhanced by decreasing compression ratio
11533c) unaflected by compression ratio
11534d) dependent on other factors
11535539
1153631. The ignition of charge by some hot surface in the engine cylinder before operation of spark plug is known as
11537a) auto ignition
11538b) preignition
11539c) retarded ignition
11540d) detonation
1154132. Ignition quality of diesel-fuel oil is expressed by an index called
11542a) octane number
11543b) cetane number
11544c) calorific value
11545d) carbon content
1154633. The specific gravity of diesel oil is
11547a) 1
11548b) 0.7
11549c) 0.85
11550d) 0.5
1155134. The specific gravity of petrol is about
11552a) 0.65
11553b) 0.75
11554c) 0.85
11555d) 0.95
1155635. Fuel consumption with increase in back pressure in engine will
11557540
11558a) increase
11559b) decrease
11560c) remain unaffected
11561d) none of the options
1156236. For same power and same speed, the flywheel of a four stroke engine as compared to two-stroke I.C. engine will be
11563a) smaller
11564b) bigger
11565c) same size
11566d) dependent on other engine parameters
1156737. Diesel engines as compared to petrol engines require
11568a) bigger flywheel
11569b) smaller flywheel
11570c) same size flywheel
11571d) no flywheel
1157238. Thermal efficiency of high speed diesel engine at design load may be of the order of
11573a) 20%
11574b) 35%
11575c) 50%
11576d) 70%
1157739. In carburettors, the top of the fuel jet with reference to the level in the float chamber is kept at
11578a) same level
11579b) slightly higher level
11580541
11581c) slightly lower level
11582d) may be anywhere
1158340. In petrol engines, advancing the spark timing will
11584a) increase the knocking tendency
11585b) decrease the knocking tendency
11586c) not affect the knocking tendency
11587d) increase or decrease knocking tendency depending on strenght and time of spark
1158841. The ignition coil in diesel engines produces voltage of the order of
11589a) 6 to 12 volts
11590b) 240 volts
11591c) 1000 volts
11592d) 20,000 volts
1159342. In petrol engine using a fixed octane rating fuel and fixed compression ratio, super charging will
11594a) increase the knocking tendency
11595b) decrease the knocking tendency
11596c) not affect the knocking tendency
11597d) unpredictable.
1159843. Deposition of carbon in petrol engine cylinder would result in increase of
11599a) clearance volume
11600b) swept volume
11601c) compression ratio
11602d) volumetric efficiency
11603542
1160444. If petrol is used in a diesel engine, then
11605a) higher knocking will occur
11606b) efficiency will be low
11607c) low power will be produced
11608d) lot of fuel will remain unburnt
1160945. For the same size and weight, a two stroke engine as compared to four stroke engine will generate power
11610a) about twice
11611b) about 0.5 times
11612c) nearly equal
11613d) about 5 times
1161446. A nozzle is said to be a convergent nozzle
11615a) when the cross-section of the nozzle increases continuously from entrance to exit
11616b) when the cross-section of the nozzle decreases continuously from entrance to exit
11617c) when the cross-section of the nozzle first decreases from entrance to throat and then increases from its throat to exit
11618d) none of the options
1161947. The most efficient method of compressing air is to compress it
11620a) isothermally
11621b) adiabatically
11622c) isentropically
11623d) isochronically
1162448. The compressor capacity with decrease in suction temperature
11625543
11626a) increases
11627b) decreases
11628c) remains unaffected
11629d) may increase or decrease depending on compressor capacity
1163049. Inter cooling in compressors
11631a) cools the delivered air
11632b) results in saving of power in compressing a given volume to given pressure
11633c) is the standard practice for big compressors
11634d) enables compression in two stages
1163550. Ratio of indicated power and brake power of air compressor is known as
11636a) mechanical efficiency
11637b) volumetric efficiency
11638c) isothermal efficiency
11639d) relative efficiency
1164051. The ratio of work doen per cycle to the swept volume in case of compressor is called
11641a) compression index
11642b) compression ratio
11643c) mean effective pressure
11644d) compressor effectiveness
1164552. Cylinder clearance in a compressor should be
11646a) as large as possible
11647b) as small as possible
11648c) about 50% of swept volume
11649544
11650d) none of the options
1165153. Volumetric efficiency of air compressor is
11652a) the ratio of the air actually delivered to the amount of piston displacement
11653b) the ratio of stroke volume to clearance volume
11654c) reciprocal of compression ratio
11655d) index of compressor performance
1165654. Volumetric efficiency of a compressor with clearance volume
11657a) increases with increase in compression ratio
11658b) decreases with increase in compression ratio
11659c) in not dependent upon compression ratiomay increase/decrease depending on compressor capacity
11660d) None of the options
1166155. A compressor at high altitude will draw
11662a) more power
11663b) less power
11664c) same power
11665d) none of the options
1166656. The advantage of multistage compression over single stage compression is
11667a) lower power consumption per unit of air delivered
11668b) decreased discharge temperature
11669c) higher volumetric efficiency
11670d) all the options
11671545
1167257. For minimum work in multistage compression, assuming same index of compression in all stages
11673a) work done in first stage should be more
11674b) work done in subsequent stages should increase
11675c) work done in all stages should be equal
11676d) work done in subsequent stages should decrease
1167758. The volumetric efficiency of compressor with increase in compression ratio will
11678a) increase
11679b) decrease
11680c) remain same
11681d) none of the options
1168259. steam nozzle covert
11683a) heat energy of steam into kinetic energy
11684b) potential energy of steam into kinetic energy
11685c) kinetic energy of steam into mechanical energy
11686d) heat energy of steam into mechanical energy
1168760. The smallest section in nozzle is known as
11688a) throat
11689b) venturi
11690c) convergent
11691d) divergent
1169261. In a nozzle, whole frictional loss is assumed to occur between
11693a) inlet and outlet
11694546
11695b) throat and exit
11696c) inlet and thoroat
11697d) all the options
1169862. The critical pressure ratio for initially superheated steam is
11699a) 0.58
11700b) 0.546
11701c) 0.56
11702d) 0.601
1170363. The flow through a nozzle is regarded as
11704a) isothermal flow
11705b) constant volume flow
11706c) constant pressure flow
11707d) isentropic flow
1170864. The supersaturated flow of steam through a nozzle as compared to a stable flow, the available heat drop
11709a) is unpredictable
11710b) increases
11711c) decreases
11712d) remains the same
1171365. The steam leaves the nozzle at a
11714a) low pressure and a low velocity
11715b) high pressure and a low velocit
11716c) high pressure and a high velocity
11717547
11718d) low pressure and a high velocity
1171966. Thermal equilibrium means that the flow of steam is
11720a) hyperbolic
11721b) polytropic
11722c) isothermal
11723d) isentropic
1172467. Which of the following statement is correct?
11725a) The pressure of steam at throat is called critical pressure.
11726b) The friction in the nozzle increases the dryness fraction of steam
11727c) The expansion of steam in a nozzle follows Rankine cycle.
11728d) all the options
1172968. The difference of supersaturated temperature and saturation temperature at that pressure in steam nozzle is called
11730a) degree of undercooling
11731b) degree of supersaturation
11732c) degree of superheat
11733d) none of the options
1173469. The variation of steam pressure in the nozzle depends upon
11735a) velocity of steam
11736b) specific volume of steam
11737c) dryness fraction of steam
11738d) all the options
11739548
1174070. The ratio of the useful heat drop to the isentropic heat drop is called
11741a) nozzle efficiency
11742b) condenser efficiency
11743c) boiler efficiency
11744d) vacuum efficiency
1174571. The critical pressure ratio for initially dry saturated steam is
11746a) 0.58
11747b) 0.546
11748c) 0.59
11749d) 0.601
1175072. The density of supersaturated steam is about __________ that of the ordinary saturated vapour at the corresponding pressure.
11751a) 4 times
11752b) same as
11753c) 2 times
11754d) 8 times
1175573. The effect of supersaturation is that the
11756a) exit velocity of steam reduces
11757b) mass of the steam discharged increases
11758c) entropy and specific volume of the steam increases
11759d) all the options
1176074. Which of the following cycles uses air as the refrigerant
11761a) Ericsson
11762549
11763b) Stirling
11764c) Carnot
11765d) Bell-coleman
1176675. Ammonia-absorption refrigeration cycle requires
11767a) very little work input
11768b) maximum work input
11769c) nearly same work input as for vapour compression cycle
11770d) zero work input
1177176. The relative coefficient of performance is
11772a) actual COP/theoretical COP
11773b) theoretical COP/actual COP
11774c) actual COP x theoretical COP
11775d) None of the options
1177677. In vapour compression cycle, the condition of refrigerant is saturated liquid
11777a) After passing through the condenser
11778b) before passing through the condenser
11779c) after passing through the expansion throttle valve
11780d) before entering the compressor
1178178. One ton of refrigeration is equal to the refrigeration effect corresponding to formation
11782a) in 1 hour
11783b) in 1 minute
11784c) in 24 hours
11785550
11786d) in 12 hours
1178779. The refrigerant for a refrigerator should have
11788a) high sensible heat
11789b) high total heat
11790c) high latent heat
11791d) low latent heat
1179280. The COP of a domestic refrigerator
11793a) is less than 1
11794b) is more than 1
11795c) is equal to 1
11796d) depends upon the make
1179781. Air refrigeration systems operates on
11798a) Carnot cycle
11799b) Reversed Carnot cycle
11800c) Rankine cycle
11801d) Reversed Brayton cycle.
1180282. One of the purposes of sub-cooling the liquid refrigerant is to
11803a) reduce compressor overheating
11804b) reduce compressor discharge temperature
11805c) increase cooling effect
11806d) Increase the compressor work input
11807551
1180883. A refrigeration cycle operates between condenser temperature of + 27°C and evaporator temperature of- 23°C. The Cannot coefficient of performance of cycle will be
11809a) 0.2
11810b) 1.2
11811c) 5
11812d) 10
1181384. In vapour compression refrigeration system, refrigerant occurs as liquid and vapour between
11814a) condenser and expansion valve
11815b) compressor and evaporator
11816c) expansion valve and evaporator
11817d) compressor and condenser
1181885. In a vapour compression refrigeration cycle, the flow of refrigerant is controlled by
11819a) compressor
11820b) condenser
11821c) evaporator
11822d) expansion valve
1182386. Where does the lowest temperature occur in a vapour compression cycle ?
11824a) condenser
11825b) evaporator
11826c) compressor
11827d) expansion valve
1182887. Superheating in a refrigeration cycle
11829a) increases COP
11830552
11831b) decreases COP
11832c) COP remains unaltered
11833d) unpredictable.
1183488. Sub-cooling in a refrigeration cycle
11835a) increases COP
11836b) decreases COP
11837c) COP remains unaltered
11838d) unpredictable
1183989. The difference between dry bulb temperature and wet bulb temperature, is called
11840a) degree of saturation
11841b) dry bulb depression
11842c) dew point depression
11843d) wet bulb depression
1184490. In aqua-ammonia and Lithium bromide - water vapour absorption refrigeration systems, the refrigerants are
11845a) water and water
11846b) water and lithium bromide
11847c) ammonia and lithium bromide
11848d) ammonia and water
1184991. During adiabatic saturation process on unsaturated air __________ remains constant.
11850a) relative humidity
11851b) dew point temperature
11852c) dry bulb temperature
11853553
11854d) wet bulb temperature
1185592. In a psychrometric process, the sensible heat added is 30 kJ/s and the latent heat added is 20 kJ/s. The sensible heat factor for the process will be
11856a) 0.37
11857b) 0.3
11858c) 0.6
11859d) 0.67
1186093. In a vapor compression refrigeration cycle, heat is rejected by the refrigerant in a
11861a) condenser
11862b) compressor
11863c) evaporator
11864d) expansion valve
1186594. During humidification process, __________ increases.
11866a) wet bulb temperature
11867b) dry bulb temperature
11868c) specific humidity
11869d) relative humidity
1187095. The curved lines on a psychrometric chart indicates
11871a) dry bulb temperature
11872b) wet bulb temperature
11873c) dew point temperature
11874d) relative humidity
11875554
1187696. During sensible cooling of air __________ decreases.
11877a) wet bulb temperature
11878b) relative humidity
11879c) specific humidity
11880d) dry bulb temperature
1188197. Which of the following statement is correct?
11882a) The wet bulb temperature is a measure of enthalpy of moist air.
11883b) The constant enthalpy lines are also constant wet bulb temperature lines
11884c) The wet bulb and dry bulb temperature are equal at saturation condition.
11885d) all the options
1188698. One tonne of refrigeration (1TR) means that the heat removing capacity is
11887a) 420 kJ/min
11888b) 210 kJ/min
11889c) 21 kJ/min
11890d) 620 kJ/min
1189199. In a saturated air-water vapour mixture, the
11892a) dry bulb, wet bulb and dew point temperature are same
11893b) dew point temperature is lower than wet bulb temperature
11894c) dry bulb temperature is higher than wet bulb temperature
11895d) dry bulb temperature is higher than dew point temperature
11896100. The wet bulb depression is zero when relative humidity is
11897a) 50%
11898b) zero %
11899555
11900c) 75%
11901d) 100%
11902101. The comfort conditions in air conditioning are at (where DBT = Dry bulb temperature, and RH = Relative humidity)
11903a) 20°C DBT and 80% RH
11904b) 25°C DBT and 100% RH
11905c) 22°C DBT and 60% RH
11906d) 25°C DBT and 40% RH
11907102. In chemical dehumidification process,
11908a) dry bulb temperature increases
11909b) wet bulb temperature decreases
11910c) dew point temperature decreases
11911d) all the options
11912103. The dry bulb temperature lines, on the psychrometric chart are
11913a) vertical and uniformly spaced
11914b) horizontal and uniformly spaced
11915c) horizontal and non-uniformly spaced
11916d) curved lines
11917104. A low wet bulb temperature indicates very __________ humidity.
11918a) low
11919b) high
11920c) low or high depends on other properties
11921d) None of the options
11922556
11923105. A mixture of dry air and water vapour, when the air has diffused the maximum amount of water vapour into it, is called
11924a) dry air
11925b) moist air
11926c) saturated air
11927d) specific humidity
119281. Ratio of work done per cycle to the stroke volume of the compressor is know as
11929a) compression ratio
11930b) compressor capacity
11931c) mean effective pressure
11932d) compressor efficiency
119332. Find the volumetric efficiency of the compressor if air is compressed from 1 bar to 7 bar. The expansion and compression are isentropic (n=1.3)and the clearance volume is 3% of stroke volume.
11934a) 76.2%
11935b) 85.1%
11936c) 89.6 %
11937d) 91.5%
119383. The ratio of high temperature to low temperature in reversed carnot cycle refrigerator is 1.1. The COP of the refrigerator will be
11939557
11940a) 10
11941b) 4
11942c) 3.5
11943d) 4.5
119444. The most suitable method for increasing the COP of vapour compression system is
11945a) sub cooling
11946b) lowering the suction pressure
11947c) Increasing the delivery pressure
11948d) None of the answers
119495. Superheating in vapour compression refrigeration cycle is
11950a) Increases the specific volume of refrigerant vapour
11951b) Increases refrigeration effect
11952c) Increases work of compression
11953d) All the answers
119546. The work input to air compressor is minimum if the compression law followed is
11955a) PV1.35= C
11956b) PV = C
11957c) PVγ = C
11958d) None of the answers
119597. A 20 m3 of air per minute is minimum power required to drive the compressor with 2-stage compression. Assume the index of compression is 1.3.
11960a) 68.2 kW
11961b) 88.9 kW
11962558
11963c) 78.8 kW
11964d) 58.8 kW
119658. In a single stage air-compressor, the clearance volume is 1/19th of the swept volume. It delivers 7.6 m3 of free air per minute from 100 kpa to 900 kpa. Assume the index of compression and expansion as 1.2. Find the volumetric efficiency of compressor
11966a) 72.4 %
11967b) 82.4 %
11968c) 62.4 %
11969d) 90.4 %
11970nozzle. Calculate the velocity of steam at exit.
11971a) 618 m/s
11972b) 718 m/s
11973c) 918 m/s
11974d) 818 m/s
1197510. Dry saturated steam enters into steam nozzle at 12 bar and discharges at 1.5 bar. The dryness fraction of exit steam is 0.95. Find the exit velocity if, initial velocity is 135 m/s.
11976a) 847.5 m/s
11977b) 747.7 m/s
11978c) 647.7 m/s
11979d) 452 m/s
1198011. In three stage reciprocating air-compressor how will the diameter of the cylinder when the air is moving from L.P cylinder to H.P cylinder via I.P. cylinder. (D = diameter of cylinder)
11981559
11982a) D L.p= D I.P= D H.P
11983b) D L.p > D I.P >D H.P
11984c) D L.p < D I.P < D H.P
11985d) D L.p =D I.P = D H.P=0
1198612. Antiknock character of compression ignition engine fuel is increased by
11987a) Amyl nitrate
11988b) Tetra ethyl lead
11989c) Lead ethide
11990d) Napthane
1199113. Engine cooling beyond optimal limit usually results into
11992a) decrease in thermal efficiency
11993b) decrease in combustion efficiency
11994c) decrease in mechanical efficiency
11995d) all the answers
1199614. The antifreeze solutions commonly used in automobiles is
11997a) Ethylene glycol
11998b) Normal – heptane
11999c) Iso-octane
12000d) Lead ethyl
1200115. A lubrication system in which a scoop connected at the lowest part of the connecting rod is used to spread the lubricating oil on the cylinder wall is called
12002a) petroil system
12003b) splash system
12004560
12005c) pressure system
12006d) dry sump system
1200716. The time duration for which both the intake and exhaust valves are remain in open position is ___________
12008a) Turbo lag
12009b) Valve overlap
12010c) Scavenging
12011d) Tappet clearance
1201217. A 40 kW engine has a mechanical efficiency of 80 %. If the frictional power is assumed to be constant with load, what is
12013the approximate value of the mechanical efficiency at 50% of the rated load?
12014a) 47%
12015b) 57%
12016c) 67%
12017d) 77%
1201818. During Morse test on a 4 cylinder engine, the following measurements of brake power were taken at constant speed. The The mechanical efficiency of the engine is ___________
12019All cylinders firing 3037 kW
12020Number 1 cylinder not firing 2102 kW
12021Number 2 cylinder not firing 2102 kW
12022Number 3 cylinder not firing 2100 kW
12023Number 4 cylinder not firing 2098 kW
12024a) 81.07%
12025b) 78.23%
12026561
12027c) 61.22%
12028d) 91.53%
1202919. ____________ valve is the bypass valve which will control the turbine speed in turbocharger
12030a) Inlet valve
12031b) Waste gate valve
12032c) Exhaust valve
12033d) Check valve
1203420. The pressure difference between the atmospheric pressure and the throat pressure is called as _________
12035a) Carburettor depression
12036b) Injection pressure
12037c) Volatility of fuel
12038d) All the above
1203921. In computing the engine performance, the heating value of fuel used is _______________
12040a) Higher heating value
12041b) Lower heating value
12042c) The Average of lower and higher heating values
12043d) None of the above
1204422. Friction power of the IC engine will _________ if the engine speed is increased.
12045a) increases
12046b) decreases
12047c) no effect
12048d) depends of other engine torque
12049562
1205023. Effectiveness of an engine’s induction process is called as _______________
12051a) volumetric efficiency
12052b) thermal efficiency
12053c) mechanical efficiency
12054d) relative efficiency
1205524. Mean piston speed of IC engine is equal to
12056a) Stroke x rpm
12057b) (stroke x rpm)/ 2
12058c) 2 x stroke x rpm
12059d) 4 x stroke x rpm
1206025. The thermostat in IC engines permitting hot water to go to radiator is set around
12061a) 70 - 80ºC
12062b) 80-85 ºC
12063c) Above 100 ºC
12064d) below 50 ºC
1206526. Incase of the pump circulation system, the pump is driven by
12066a) flywheel
12067b) engine crankshaft
12068c) cam shaft
12069d) generator
1207027. The component of the water cooling system which exchanges heat with the outside air is called
12071563
12072a) radiator
12073b) thermostat
12074c) pump
12075d) fan
1207628. The commercial refrigeration system which is closer to reversed carnot cycle in terms of performance is
12077a) Vapour compression cycle
12078b) vapour absorption cycle
12079c) Air refrigeration system
12080d) cryogenic system
1208129. The air refrigeration system is working on _____________________ cycle
12082a) bell column cycle
12083b) carnot cycle
12084c) driving cycle
12085d) VCR cycle
1208630. The amount of heat removed from 1 ton (1000 kg) of pure water supplied at 00C to form ice at 00C in 24 hours is known as _______________
12087a) One TR
12088b) 3.5 kW
12089c) 14000 kJ/hr
12090d) all the answers
1209131. Fundamental principle of refrigeration is based on _____________ law of thermodynamics
12092a) First
12093564
12094b) second
12095c) third
12096d) none of the above
1209732. The main function of ___________ is to collapse the primary circuit for EMF generation in battery ignition system.
12098a) Battery
12099b) Capacitor and breaker points
12100c) Ignition coil
12101d) rocker arm
1210233. A refrigerant should have low
12103a) boiling point
12104b) specific heat of liquid
12105c) specific volume of vapour
12106d) all of the answers
1210734. In reciprocating compressors, clearance is provided
12108a) To improve the volumetric efficiency of the compressor
12109b) To accommodate valves
12110c) To account for thermal expansion due to temperature variation
12111d) To reduce power consumption of the compressor
1211235. The temperature recorded by a thermometer when its bulb is surrounded by a wet cloth exposed to air.
12113a) Dry-bulb temperature
12114b) Wet-bulb temperature
12115c) Dew point temperature
12116565
12117d) None of the answers
1211836. It is the temperature recorded by a thermometer when water vapour in air begins to condense or dew is formed.
12119a) Dry bulb temperature
12120b) Wet-bulb temperature
12121c) Dew point temperature
12122d) All the answers
1212337. The mass of water vapour present in 1kg of dry air and is expressed as g/kg of air
12124a) Humidity ratio
12125b) Absolute humidity
12126c) Degree of Saturation
12127d) Relative humidity
1212838. ___________gives the fraction of air which does not come into contact with heating coil surface
12129a) By pass factor
12130b) sensible heat factor
12131c) latent heat factor
12132d) total heat factor
1213339. _____________of air depends on the dew point temperature of air
12134a) latent heat
12135b) sensible heat
12136c) total heat
12137d) none of the answers
12138566
1213940. Humidification or Dehumidification process is also called as
12140a) sensible heat process
12141b) latent heat process
12142c) total heat process
12143d) all the answers
1214441. Cooling with adiabatic humidification Process is known as
12145a) Evaporative cooling
12146b) Adiabatic chemical dehumidification
12147c) cooling and dehumidification
12148d) heating and humidification
12149567
12150Turbomachines
121511. Specific enthalpy and velocity of steam at inlet and exit of a steam turbine, running under steady
12152state, are as given below:
12153&nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp Specific enthalpy (kJ/kg) &nbsp &nbsp &nbsp &nbsp Velocity (m/s)
12154Inlet steam condition &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp3250 &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp 180
12155Exit steam condition &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp 2360 &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp 5
12156The rate of heat loss from the turbine per kg of steam flow rate is 5 kW. Neglecting changes in
12157potential energy of steam, the power developed in kW by the steam turbine per kg of steam flow rate, is
12158a) 901.2
12159b) 911.2
12160c) 17072.5
12161d) 17082.5
121622. Steam at a velocity of 10 m/s enters the impulse turbine stage with symmetrical blading having blade angle 30<sup>0</sup>. The enthalpy drop in the stage is 100 kJ. The nozzle angle is 20<sup>0</sup>. The maximum blade efficiency (in percent) is
12163a) 88.3
12164b) 85.2
12165c) 81.3
12166d) 84.7
12167568
121683. In a pelton Wheel the bucket peripheral speed is 10 m/s, the water jet velocity is 25 m/s and volumetric flow rate of the jet is 0.1m<sup>3</sup>/s. If the jet defection angle is 120<sup>0</sup> and the flow is ideal, the power developed is
12169a) 7.5 kW
12170b) 15 kW
12171c) 22.5 kW
12172d) 37.5 kW
121734. Specific speed of a Kaplan Turbine ranges between
12174a) 30 to 60
12175b) 60 to 300
12176c) 300 to 600
12177d) 600 to 1000
121785. Cavitation in hydraulic turbine is most likely to occur at the turbine
12179a) entry
12180b) exit
12181c) stator exit
12182d) rotor exit
121836. For a single stage impulse turbine with a rotor diameter of 2 m and a speed of 3000 rpm when the
12184nozzle angle is 20<sup>0</sup>, the optimum velocity of steam in m/s is
12185a) 334
12186b) 356
12187c) 668
12188d) 711
12189569
121907. A Curtis stage, Rateau stage and a 50% reaction stage in a steam turbine are examples of
12191a) different types of impulse stages
12192b) different types of reaction stages
12193c) a simple impulse stage, a velocity compounded impulse stage and reaction stage
12194d) velocity compounded impulse stage, a simple impulse stage and a reaction stage
121958. The isentropic heat drop in the nozzle of an impulse steam turbine with a nozzle efficiency 0.9, blade
12196velocity ratio 0.5, and mean blade velocity 150 m/s in kJ/kg is
12197a) 50
12198b) 40
12199c) 60
12200d) 75
122019. Considering the variation of static pressure and absolute velocity in an impulse stream turbine,
12202across one row of moving blades
12203a) both pressure and velocity decrease
12204b) pressure decreases but velocity increases
12205c) pressure remains constant, while velocity increases
12206d) pressure remains constant, while velocity decreases
12207570
12208TURBOMACHINES
122091. In a reaction turbine the enthalpy drop in a stage is 60 units. The enthalpy drop in the fixed blades is 28 units. What is the degree of reaction?
12210a) 0.284
12211b) 0.533
12212c) 0.466
12213d) 1.875
122142. In case of a centrifugal pump, cavitation will occur if
12215a) it operates above the minimum net positive suction head
12216b) it operates below the minimum net positive suction head
12217c) the pressure at the inlet of the pump is above the atmospheric pressure
12218d) the pressure at the inlet of the pump is equal to the atmospheric pressure
122193. Manometric efficiency of a centrifugal pump is defined as the ratio of
12220a) suction head to the head imparted by the impeller to water
12221b) head imparted by the impeller to water to the suction head
12222c) manometric head to the head imparted by the impeller to water
12223d) manometric head to the head imparted by the impeller to water
122244. A centrifugal pump delivers water at the rate of 50 litres/s against a total head of 40 metres. Then the power required to drive the pump is
12225a) 2 kW
12226b) 15.2 kW
12227c) 19.6 kW
12228d) 25.8 kW
12229571
122305. Match list 1 with list 2 and select the correct answer using the codes given below the lists:
12231List 1 List 2
12232A. Head race 1. Channel, tunnel or pipes through which water is carried from reservoir to the turbine
12233B. Tail race 2. Reservoir water level
12234C. Penstock 3. Diverging tube discharging water from the turbine to the atmosphere
12235D. Draft tube 4. The level at which water is discharged at atmospheric pressure
12236Codes:
12237a) A-1, B-3, C-2, D-4
12238b) A-2, B- 4, C-1, D-3
12239c) A-1, B-4, C-2, D-3
12240d) A-2, B-3, C-1 ,D-4
122416. Considering the variation of static pressure and absolute velocity in an impulse steam turbine, across one row of moving blades
12242a) pressure remains constant, while velocity decreases
12243b) pressure decreases but velocity increases
12244c) both pressure and velocity decrease
12245d) pressure remains constant, while velocity increases
122467. In an axial flow impulse turbine, energy transfer takes place due to
12247a) Change in relative kinetic energy
12248b) Change in absolute kinetic energy
12249c) Change in pressure energy
12250d) Change in energy because of centrifugal force
122518. An axial flow compressor has
12252572
12253a) larger blades at gas entry and smaller blades at exit
12254b) smaller blades at gas entry and larger blades at exit
12255c) identical blades at exit as well as entry
12256d) size of blades remains same only angles changes
122579. In a steady, irreversible adiabatic, incompressible flow process; in the absence of work transfer:
12258a) The total pressure decreases but total temperature remains constant
12259b) Total pressure and total temperature decrease
12260c) Total pressure and total temperature remain constant
12261d) Total pressure and total temperature remain constant
1226210. Francis turbine is
12263a) A reaction radial flow turbine
12264b) An axial flow turbine
12265c) An impulse turbine
12266d) A tangential flow turbine
1226711. The hydraulic efficiency of a reaction turbine, is the ratio of
12268a) actual work available at the turbine to energy imparted to the wheel
12269b) power produced by the turbine to the energy actually supplied by the turbine
12270c) workdone on the wheel to the energy (or head of water) actually supplied to the turbine
12271d) none of the above
1227212. Consider the following characteristics:
122731. The fluid enters the pump axially and is discharged radially
122742. Maximum efficiency may be of the order of 90%
12275573
122763. Development of a low head
122774. A limited suction capacity
12278Which of the above characteristics are possessed by axial flow pumps?
12279a) 1 and 2
12280b) 2 and 3
12281c) 2 and 4
12282d) 3 and 4
1228313. In a four stage compressor, if the pressure at the first and third stage are 1 bar and 16 bar, then the delivery pressure at the fourth stage will be
12284a) 256 bar
12285b) 64 bar
12286c) 1 bar
12287d) 16 bar
1228814. Do self priming pumps require priming ever? Assume the pipings are perfect and leak proof.
12289a) Yes, once when it is installed
12290b) No, doesn't require priming at all
12291c) Yes, always
12292d) Cannot say
1229315. While flowing through the rotor blades in an axial flow air compressor, the relative velocity of air:
12294a) Continuously increases
12295b) Continuously decreases
12296c) First increases and then decreases
12297d) First decreases and then increases
12298574
1229916. A centrifugal pump will start delivering liquid only when the pressure rise in the impeller is equal to the
12300a) velocity head
12301b) manometric head
12302c) static head
12303d) kinetic head
1230417. Which one of the following statements is true?
12305a) In a multi-stage compressor, overall efficiency is less than stage efficiency
12306b) Preheat factor for a multi-stage compressor is greater than one
12307c) In a multi-stage turbine, overall e-efficiency is less than the stage e-efficiency
12308d) Preheat factor does not affect the multi-stage compressor performance
1230918. Which of the followings are the demerits of single impulse stage
123101. Requirement of C-D nozzle
123112. Enhanced shock associated losses
123123. More boundary layer associated losses in comparison with single reaction stage
12313a) 1 and 2 only
12314b) 2 and 3 only
12315c) 1 and 3 only
12316d) 1,2 and 3
1231719. The isentropic heat drop in the nozzle of an impulse steam turbine with a nozzle efficiency 0.9, blade velocity ratio 0.5, and mean blade velocity 150 m/s in kJ/kg is
12318a) 50
12319b) 40
12320575
12321c) 60
12322d) 75
1232320. Steam enters the rotor of a reaction turbine with an absolute velocity of 236 m/s and the relative velocity of 132 m/s. It leaves the rotor with a relative velocity of 232 m/s absolute velocity of 126 m/s. The specific work output is
12324a) 38.1 kJ/kg
12325b) 40.1 kJ/kg
12326c) 43.8 kJ/kg
12327d) 47.4 kJ/kg
1232821. The degree of reaction of a turbine is the ratio of enthalpy drop in
12329a) moving blades to enthalpy drop in fixed blades
12330b) fixed blades to enthalpy drop in moving blades
12331c) moving blades to enthalpy drop in the stage
12332d) fixed blades to enthalpy drop in the stage
1233322. At the inlet of a steam nozzle, stagnation enthalpy of steam is 787.07 kcal/kg at exit, the static enthalpy of steam is 738.0 kcal/kg. For a frictionless adiabatic flow, the velocity of steam at the exit will be (assume 1kcal = 4.18kJ)
12334a) 620 m/s
12335b) 582.2 m/s
12336c) 600.6 m/s
12337d) 640.5 m/s
1233823. In the phenomenon of cavitation, the characteristic fluid property involved is
12339a) bulk modulus of elasticity
12340576
12341b) vapour pressure
12342c) surface tension
12343d) viscosity
1234424. Which of the following statement is wrong?
12345a) For the same overall size and rotational speed, pressure rise obtained with radial impeller is lower than that of forward
12346swept impeller
12347b) For the same overall size and rotational speed Backward swept impeller generates minimum pressure rise
12348c) For the same overall size and rotational speed, all three types of impellers generate same pressure rise
12349d) For the same overall size and rotational speed forward swept impeller generates maximum pressure rise
1235025. The static temperature and Mach number at the inlet of a centrifugal compressor are 30<sup>0</sup>C and 0.5 respectively. The stagnation
12351temperature of the air at the inlet will be:
12352a) 34.6 degree Celcius
12353b) 45.15 degree Celcius
12354c) 60.3 degree Celcius
12355d) 31.5 degree Celcius
1235626. An impulse turbine produces 50 kW of power when the blade mean speed is 400 m/s. What is the rate of change of momentum tangential to the rotor?
12357a) 150 N
12358b) 200 N
12359c) 125 N
12360d) 175 N
12361577
1236227. Euler equation for turbomachines is derived on the basis of
12363a) Rate of change of angular momentum
12364b) Conservation of mass
12365c) Rate of change of velocity
12366d) Rate of change of linear momentum
1236728. Consider the following statements:
12368Cavitation in hydraulic machines occurs at the
123691. Exit of a pump 2. Entry of the pump 3. Exit of a turbine.
12370Of these statement
12371a) 2 and 3 are correct.
12372b) 1 and 3 are correct
12373c) 1, 2 and 3 are correct
12374d) 1 and 2 are correct
1237529. Surging basically implies
12376a) forward motion of air at a speed above sonic velocity.
12377b) the surging action due to the blast of air produced in a compressor.
12378c) unsteady, periodic and reversed flow.
12379d) Only by increasing the tip speed
1238030. The total and static pressures at the inlet of a steam nozzle are 186 kPa and 178 kPa respectively. If the total pressure at the exit is 180 kPa and static pressure is 100 kPa, then the loss of energy per unit mass in the nozzle will be:
12381a) 2 kPa
12382b) 6 kPa
12383c) 8 kPa
12384578
12385d) 78 kPa
1238631. Stalling of blades in axial- flow compressor is the phenomenon of
12387a) motion of air at sonic velocity
12388b) unsteady, periodic and reversed flow
12389c) air steam not able to follow the blade contour
12390d) air stream blocking the passage
1239132. Which one of the following is used to bring down the speed of an impulse steam turbine to practical limits?
12392a) A centrifugal governor
12393b) Compounding of the turbine
12394c) A large flywheel
12395d) A gear box
1239633. In aircraft gas turbines, the axial flow compressor is preferred because
12397a) of high pressure rise per stage
12398b) of high pressure rise
12399c) it is stall free
12400d) of low frontal area
1240134. The pressure rise in the impeller of centrifugal compressor is achieved by
12402a) the centrifugal action and decrease in volume
12403b) the centrifugal and diffusion action
12404c) the decrease in volume and diffusion action
12405d) the centrifugal and push-pull action
12406579
1240735. Impulse turbine requires
12408a) High head and low discharge
12409b) High head and high discharge
12410c) Low head and low discharge
12411d) Low head and high discharge
1241236. A Pelton wheel develops 1750 kW under a head of 100 metres while running at 200 r.p.m. and discharging 2500 litres of water per second. The unit power of the wheel is
12413a) 1.75 kW
12414b) 0.75 kW
12415c) 3.75 kW
12416d) 0.25 kW
1241737. In centrifugal compressor terminology, vane-less space refers to the space between
12418a) blades in the impeller
12419b) diffuser exit and volute casing
12420c) impeller tip and diffuser inlet edge
12421d) the inlet and blade inlet edge
1242238. In a gas turbine cycle, the turbine output is 600 kJ/kg, the compressor work is 400 kJ/kg and the heat supplied is
124231000 kJ/kg. The thermal efficiency of this cycle is :
12424a) 60%
12425b) 40%
12426c) 20%
12427d) 80%
12428580
1242939. An axial flow compressor stage is suitable for
12430a) high volume flow rates with a small pressure rise
12431b) high volume flow rates with high pressure rise
12432c) low volume flow rates with low pressure rise
12433d) low volume flow rates with high pressure rise
1243440. Consider the following statements about modification in a gas turbine power plant working on a simple Brayton cycle:
124351. Incorporation of regeneration process increases specific work output as well as thermal efficiency.
124362. Incorporation of regeneration process increases thermal efficiency but specific work output remains unchanged.
124373. Incorporation of inter-cooling process in a multi-stage compression increases specific work output but the heat input also increases.
124384. Incorporation of inter-cooling process in a multi-stage compression system increases specific work output, the heat addition remains unchanged.
12439Which of the above statements are correct?
12440a) 1 and 3
12441b) 2 and 3
12442c) 1 and 4
12443d) 2 and 4
1244441. In a turbojet engine, subsequent to heat addition to compressed air, to get the power output, the working substance
12445is expanded in
12446a) turbine blades, which is essentially an isochoric process.
12447b) turbine blades, which is essentially an isentropic process.
12448c) exit nozzle, which is essentially an isentropic process.
12449d) exit nozzle, which is a constant volume process.
12450581
1245142. A Francis turbine is used when the available head of water is
12452a) 0 to 25 m
12453b) 25 m to 250 m
12454c) 250 m to 500 m
12455d) Above 500 m
1245643. Steam enters De Laval steam turbine with an inlet velocity of 30 m/s and leaves with an outlet velocity of 10 /s. the work done by one kg of steam is
12457a) 400 Nm
12458b) 600 Nm
12459c) 800 Nm
12460d) 1200 Nm
1246144. At a particular section of a reaction turbine, the diameter of the blade is 1.8m, the velocity of flow of steam is
1246249m/s and the quantity of steam flow is 5.4m<sup>3</sup>/s. The blade height at this section will be approximately:
12463a) 2 cm
12464b) 1 cm
12465c) 0.5 cm
12466d) 4 cm
1246745. In a centrifugal compressor, how can the pressure ratio be increased?
12468a) By increasing the tip speed and decreasing the inlet temperature
12469b) Only by increasing the inlet temperature
12470c) Only by decreasing the inlet temperature
12471d) Only by increasing the tip speed
12472582
1247346. The main aim of compounding of steam turbine is to
12474a) avoid steam condensation
12475b) reduce steam consumption
12476c) reduce rotor speed
12477d) improve efficiency
1247847. A draft tube is not required for a
12479a) Francis turbine
12480b) Kaplan turbine
12481c) Pelton wheel turbine
12482d) Propeller turbine
1248348. A multistage compressor is to be designed for a given flow rate and pressure ratio. If the compressor consists of axial
12484flow stages followed by centrifugal instead of only axial flow stages, then the
12485a) axial length of the compressor would be increased
12486b) overall diameter would be decreased
12487c) overall diameter remains the same
12488d) overall diameter would be increased
1248949. In a 50% reaction stage, absolute velocity angle at inlet is 45<sup>0</sup>, mean peripheral speed is 75 m/s and the absolute velocity at the exit is axial. The stage specific work is
12490a) 2500 J/kg
12491b) 3270 J/kg
12492c) 4375 J/kg
12493583
12494d) 5625 J/kg
1249550. The Rateau turbine belongs to the category of
12496a) pressure compounded turbine
12497b) reaction turbine
12498c) velocity compounded turbine
12499d) radial flow turbine
12500TURBOMACHINES
125011. In which turbine the pressure energy of water is first completely converted into kinetic energy by means of nozzle kept close to the runner?
12502a) Impulse turbine
12503b) Reaction turbine
12504c) Both in Impulse and Reaction turbines
12505d) Nither Impulse nore in Reaction
125062. Which one of the following helps in avoiding cavitation in centrifugal pumps?
12507a) Low suction pressure
12508b) High delivery pressure
12509c) Low delivery pressure
12510d) High suction pressure
125113. In the case of pelton turbine installed in a hydraulic power plant, the grossnhead available is the vertical distance between
12512a) forebay and tail race
12513b) reservoir level and turbine inlet
12514584
12515c) forebay and turbine inlet
12516d) reservoir level and tail race.
125174. Consider the following statements:
125181. Almost all flow losses take place in the diverging part of a nozzle.
125192. Normal shocks are likely to occur in the converging part of a nozzle.
125203. Efficiency of reaction turbines is higher than that of impulse turbines.
12521Of these statements
12522a) 1, 2 and 3 are correct
12523b) 2 and 3 are correct
12524c) 1 and 2 are correct
12525d) 1 and 3 are correct
125265. Which of the following is an example of impulse turbine?
12527a) Propeller turbine
12528b) Francis turbine
12529c) Kaplan turbine
12530d) Pelton wheel
125316. Which of the following is NOT a type of positive displacement pumps?
12532a) Reciprocating pump
12533b) Rotary displacement pump
12534c) Centrifugal pump
12535d) Vane pump
125367. What is the head of water available at turbine inlet in hydro-electric power plant called?
12537a) head race
12538585
12539b) tail race
12540c) gross head
12541d) net head
125428. Which of the following components of reaction turbine increases the head on the turbine by an amount equal to the height of runner outlet above the tail race?
12543a) Scroll casing
12544b) Guide vanes
12545c) Moving vanes
12546d) Draft tube
125479. Which pump is more suitable for an application where very high pressure is required to be developed at moderate discharge?
12548a) Reciprocating pump
12549b) Centrifugal pump
12550c) Turbine
12551d) Gear pump
1255210. The ratio of actual whirl velocity to the ideal whirl velocity in the centrifugal compressor is called as
12553a) velocity factor
12554b) slip factor
12555c) work factor
12556d) flow coefficient
1255711. In a steady, reversible adiabatic, compressible flow process; in the abscence of work transfer
12558a) The total pressure decreases but total temperature remains constant
12559586
12560b) Total pressure and total temperature decrease
12561c) Total pressure and total temperature remain constant
12562d) Total pressure and total temperature remain constant
1256312. A diffuser is used to
12564a) increase velocity and decrease pressure
12565b) increase velocity as well as pressure
12566c) decrease velocity and increase pressure
12567d) decrease velocity as well as pressure
1256813. Consider the following characteristics:
125691. The fluid enters the pump axially and is discharged radially
125702. Maximum efficiency may be of the order of 90%
125713. Development of a low head
125724. A limited suction capacity
12573Which of the above characteristics are possessed by axial flow pumps?
12574a) 1 and 2
12575b) 2 and 3
12576c) 2 and 4
12577d) 3 and 4
1257814. Do reciprocating pumps require priming ever?
12579a) Yes, once when it is installed
12580b) No, it can work without priming
12581c) Yes, always
12582d) Cannot say
12583587
1258415. While flowing through the rotor blades in an axial flow air compressor, the relative velocity of air:
12585a) Continuously increases
12586b) Continuously decreases
12587c) First increases and then decreases
12588d) First decreases and then increases
1258916. Braking jet in an impulse turbine is used
12590a) to bring the runner to rest in a short time
12591b) to change the direction of runner
12592c) to break the jet of water
12593d) to stop flow from penstock
1259417. Surging basically implies
12595a) forward motion of air at a speed above sonic velocity.
12596b) the surging action due to the blast of air produced in a compressor.
12597c) unsteady, periodic and reversed flow.
12598d) Only by increasing the tip speed
1259918. Reheat factor in steam turbines depends on
12600a) stage efficiency only
12601b) initial pressure and temperature
12602c) exit pressure only
12603d) exit temperature, pressure and stage efficiency
1260419. The rotor speeds in steam turbines can be reduced by
12605a) compounding of steam turbines
12606588
12607b) scaling of steam turbines
12608c) governing of steam turbines
12609d) using reduction gear
1261020. Thermal efficiency of closed cycle gas turbine plant increases by
12611a) reheating
12612b) intercooling
12613c) intercooling, reheating and regenerator
12614d) regenerator
1261521. A gas turbine works on which one of the following cycles?
12616a) Rankine
12617b) Otto
12618c) Brayton
12619d) Stirling
1262022. Consider the following statements with regard to the specific speeds of differentvtypes of turbine:
126211. High specific speed implies that it is a Pelton wheel
126222. Medium specific speed implies that it is a Francis turbine
126233. Low specific speed implies that it is an axial flow turbine.
12624Which of these statements given above is/are correct?
12625a) 1 only
12626b) 2 only
12627c) 3 only
12628d) 1 and 3 are correct
12629589
1263023. The maximum blade efficiency of single stage impulse turbine in terms of nozzle
12631angle &#945 under ideal conditions is proportional to
12632a) cos &#945
12633b) sin &#945
12634c) sin<sup>2</sup>&#945
12635d) cos<sup>2</sup>&#945
1263624. If in an impulse turbine designed for free vortex flow, tangential velocity of stem
12637at the root radius of 250 mm is 430 m/s and the blade height is 100 mm, then the
12638tangential velocity of steam at the tip will be
12639a) 602 m/s
12640b) 504 m/s
12641c) 409 m/s
12642d) 307 m/s
1264325. If in a steam turbine stage, heat drop in moving blade ring is 40 kJ/kg and that in the fixed blade ring is 60 kJlkg, then the degree of reaction is
12644a) 20%
12645b) 40%
12646c) 60%
12647d) 70%
1264826. Which one of the following is not correct regarding both Kaplan and propeller turbines?
12649a) The runner is axial
12650b) The blades are wing type
12651c) There are four to eight blades
12652d) The blades can be adjusted
12653590
1265427. Based on the direction of flow, which one of the following turbines is different from the other three?
12655a) Pelton turbine
12656b) Parson's turbine
12657c) De Laval turbine
12658d) Kaplan turbine
1265928. Consider the following statements regarding an impulse turbine:
126601. Relative velocity at the inlet and exit of the rotor blades are the same.
126612. Absolute velocity at the inlet and exit of the rotor blades are the same.
126623. Static pressure within the rotor blade channel is constant.
126634. Total pressure within the rotor blade channel is constant.
12664Of these statements:
12665a) 1 and 4 are correct
12666b) 2 and 3 are correct
12667c) 1 and 3 are correct
12668d) 2 and 4 are correct
1266929. In hydraulic power-generation systems, sugre tanks are provided to prevent immediate damage to
12670a) draft tube
12671b) turbine
12672c) tail race
12673d) penstrocks
1267430. A nozzle is said to have choked flow when
12675a) discharge is minimum.
12676591
12677b) throat velocity is sonic.
12678c) nozzle exit pressure is more than
12679the critical pressure.
12680d) discharge is zero.
1268131. If the enthalpy drops of moving blade and fixed blade of a stage in a reaction turbine are 9 and 11 kJ/kg respectively,
12682then degree of reaction of the stage is
12683a) 0.1
12684b) 0.45
12685c) 0.55
12686d) 1.0
1268732. A centrifugal pump delivers water at the rate of 50 litres/s against a total head of 40 metres. Then the power required to drive the pump is
12688a) 2 kW
12689b) 15.2 kW
12690c) 19.6 kW
12691d) 25.8 kW
1269233. The function of the draft tube in a reaction turbine is
12693a) to enable the shaft of the turbine to
12694be vertical
12695b) to transform a large part of pressure
12696energy at turbine outlet into kinetic
12697energy
12698c) to avoid whirl losses at the exit of
12699the turbine
12700592
12701d) to transform a large part of kinetic
12702energy at the turbine outlet into
12703pressure energy