Machine Kinematics Multiple Choice Questions on “Types of Belts – 1”.
1. In a cone pulley, if the sum of radii of the pulleys on the driving and driven shafts is constant, then
a) open belt drive is recommended
b) crossed belt drive is recommended
c) both open belt drive and crossed belt drive is recommended
d) the drive is recommended depending upon the torque transmitted
Answer: b
Clarification: Cone pulley drive, is used for changing the speed of the driven shaft while the main or driving shaft runs at constant speed. This is accomplished by shifting the belt from one part of the steps to the other.
2. Due to slip of belt, the velocity ratio of the belt drive increases.
a) True
b) False
Answer: b
Clarification: The result of the belt slipping is to reduce the velocity ratio of the system.
3. When two pulleys of different diameters are connected by means of an open belt, the angle of contact at the _________pulley must be taken into consideration.
a) smaller
b) larger
c) medium
d) none of the mentioned
Answer: a
Clarification: None.
4. The power transmitted by a belt is maximum when the maximum tension in the belt is __________of centrifugal tension.
a) one-third
b) two-third
c) double
d) three times
Answer: d
Clarification: When the power transmitted is maximum, 1/3rd of the maximum tension is absorbed as centrifugal tension.
5. The velocity of the belt for maximum power is
a) T/3
b) T.g/3
c) √T/3m
d) √3m/T
Answer: c
Clarification: None.
6. The centrifugal tension on the belt has no effect on the power transmitted.
a) True
b) False
Answer: a
Clarification: None.
7. V-belts are usually used for
a) long drives
b) short drives
c) long and short drives
d) none of the mentioned
Answer: b
Clarification: V-belt is mostly used in factories and workshops where a great amount of power is to be transmitted from one pulley to another when the two pulleys are very near to each other.
8. In a multiple V-belt drive, if one of the belt is broken, then we should replace
a) the broken belt only
b) all the belts
c) the broken belt and the belts on either side of it
d) none of the mentioned
Answer: b
Clarification: In multiple V-belt drive, all the belts should stretch at the same rate so that the load is equally divided between them. When one of the set of belts break, the entire set should be replaced at the same time. If only one belt is replaced, the new unworn and unstressed belt will be more tightly stretched and will move with different velocity.
9. The included angle for the v-belt is usually
a) 100 to 200
b) 200 to 300
c) 300 to 400
d) 600 to 800
Answer: c
Clarification: None.