Theory of Machines – Mechanical Engineering Multiple Choice Questions
51. The tendency of a body to resist change from rest or motion is known as
(a) mass
(b) friction
(c) inertia
(d) resisting force
(e) resisting torque
Ans: c
53. The type of coupling used to join two shafts whose axes are neither in same straight line nor parallel, but intersect is
(a) flexible coupling
(b) universal coupling
(c) chain coupling
(d) Oldham’s coupling
(e) American coupling.
Ans: b
54. The advantage of the piston valve over D-slide valve is that in the former case
(a) wear is less
(b) power absorbed is less
(c) both wear and power absorbed are low
(d) the pressure developed being high provides tight sealing
(e) there is overall economy of initial cost, maintenance and operation.
Ans: c
55. Flexible coupling is used because
(a) it is easy to disassemble
(b) it is easy to engage and disengage
(c) it transmits shocks gradually
(d) it prevents shock transmission and eliminates stress reversals
(e) it increases shaft life.
Ans: d
56. With single Hooke’s joint it is possible to connect two shafts, the axes of which have an angular misalignment up to
(a) 10°
(b) 20°
(c) 30°
(d) 40°
(e) 60°
Ans: d
57. The Hooke’s joint consists of :
(a) two forks
(b) one fork
(c) three forks
(d) four forks
(e) five forks.
Ans: a
58. The Klein’s method of construction for reciprocating engine mechanism
(a) is based on acceleration diagram
(b) is a simplified form of instantaneous center method
(c) utilities a quadrilateral similar to the diagram of mechanism for reciprocating engine
(d) enables determination of Corioli’s component
(e) none of the above.
Ans: c
59. It is required to connect two parallel shafts, the distance between whose axes is small and variable. The shafts are coupled by
(a) universal joint
(b) knuckle joint
(c) Oldham’s coupling
(d) flexible coupling
(e) electromagnetic coupling.
Ans: c
60. The e.g. of a link in any mechanism would experience
(a) no acceleration
(b) linear acceleration
(c) angular acceleration
(d) both angular and linear accelerations
(e) none of the above.
Ans: d
61. In elliptical trammels
(a) all four pairs are turning
(b) three pairs turning and one pair sliding
(c) two pairs turning and two pairs sliding
(d) one pair turning and three pairs sliding
(e) all four pairs sliding.
Ans: c
62. In automobiles the power is transmitted from gear box to differential through
(a) bevel gear
(b) universal joint
(c) Hooke’s joint
(d) Knuckle joint
(e) Oldham’s coupling.
Ans: c
63. The indicator using Watt mechanism is known as
(a) Thompson indicator
(b) Richard indicator
(c) Simplex indicator
(d) Thomson indicator
(e) none of the above.
Ans: b
64. The Ackermann steering mechanism is preferred to the Davis type in automobiles because
(a) the former is mathematically accurate
(b) the former is having turning pair
(c) the former is most economical
(d) the former is most rigid
(e) none of the above.
Ans: b
65. Transmission of power from the engine to the rear axle of an automobile is by means of
(a) compound gears
(b) worm and wheel method
(c) Hooke’s joint
(d) crown gear
(e) bevel gears.
Ans: c
66. When a ship travels in a sea, which of the effect is more dangerous
(a) steering
(b) pitching
(c) rolling
(d) all of the above
(e) none of the above.
Ans: b
67. In an ideal machine, the output as compared to input is
(a) less
(b) more
(c) equal
(d) may be less or more depending on efficiency
(e) always less.
Ans: c
68. Governor is used in automobile to
(a) decrease the variation of speed
(b) to control
(c) to control SN
(d) all of the above
(e) none of the above.
Ans: c
69. In gramophones for adjusting the speed of the turntable, the following type of governor is commonly employed
(a) Hartung governor
(b) Wilson Hartnell governor
(c) Pickering governor
(d) Inertia governor
(e) none of the above.
Ans: c
70. For fluctuating loads, welsuited bearing is
(a) ball bearing
(b) roller bearing
(c) needle roller bearing
(d) thrust bearing
(e) sleeve bearing.
Ans: c
71. Crowning on pulleys helps
(a) in increasing velocity ratio
(b) in decreasing the slip of the belt
(c) for automatic adjustment of belt position so that belt runs centrally
(d) increase belt and pulley life
(e) none of the above.
Ans: c
72. Idler pulley is used
(a) for changing the direction of motion of the belt
(b) for applying tension
(c) for increasing -velocity ratio
(d) all of the above
(e) none of the above.
Ans: b
73. In multi-V-belt transmission, if one of the belt is broken, we have to change the
(a) broken belt
(b) broken belt and its adjacent belts
(c) all the belts
(d) there is no need of changing any one as remaining belts can take care of transmission of load
(e) all the weak belts.
Ans: c
74. The moment on the pulley which produces rotation is called
(a) inertia
(b) momentum
(c) moment of momentum
(d) work
(e) torque.
Ans: e
75. Creep in belt drive is due to
(a) material of the pulley
(b) material of the belt
(c) larger size of the driver pulley
(d) uneven extensions and contractions due to varying tension
(e) expansion of belt.
Ans: d