101. For the brake to be self locking, the force P at C shown in the below figure, should
be zero
act in upward direction
act in downward direction
none of these
✅ The correct answer is option A.
Theory of machines MCQs
102. Maximum fluctuation of energy in a flywheel is equal to (where I = Mass moment of inertia of the flywheel, E = Maximum fluctuation of energy, CS = Coefficient of fluctuation of speed, and ω = Mean angular speed = )
Iω(ω1 – ω2)
Iω2CS
2ECS
all of these
✅ The correct answer is option D.
103. The maximum fluctuation of speed is the
difference of minimum fluctuation of speed and the mean speed
difference of the maximum and minimum speeds
sum of maximum and minimum speeds
variations of speed ab
✅ The correct answer is option B.
104. The periodic time of a compound pendulum is __________ when the distance between the point of suspension and the centre of gravity is equal to the radius of gyration of the body about its centre of gravity.
zero
minimum
maximum
✅ The correct answer is option B.
105. The controlling force diagram for a spring controlled governor is a curve passing through the origin.
Yes
No
✅ The correct answer is option B.
106. The displacement of the reciprocating roller follower, when it has contact with the straight flanks of the tangent cam, is given by (where r1 = Minimum radius of the cam, r2 = Radius of the roller follower, and θ = Angle turned by the cam from the beginning of the follower displacement)
(r1 – r2)(1 – cosθ)
(r1 + r2)(1 + cos θ)
(r1 – r2)
(r1 + r2)
✅ The correct answer is option D.
107. 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
governor A is more sensitive than governor B
governor B is more sensitive than governor A
both governors A and B are equally sensitive
none of the above
✅ The correct answer is option A.
108. If the number of links in a mechanism are equal to l, then the number of possible inversions are equal to
l – 2
l – 1
l
l + 1
✅ The correct answer is option C.
109. The distance by which the __________ of the D-slide valve overlaps the steam port is called exhaust lap.
inner edge
outer edge
✅ The correct answer is option A.
110. The critical speed of a shaft depends upon its
mass
stiffness
mass and stiffness
stiffness and eccentri
✅ The correct answer is option C.