Engineering Questions with Answers - Multiple Choice Questions

Machine Kinematics MCQ – V-Belts

1 - Question

The included angle for the V-belt is usually
a) 20° – 30°
b) 30° – 40°
c) 40° – 60°
d) 60° – 80°

Explanation: The V-belts are made of fabric and cords moulded in rubber and covered with fabric and rubber. These belts are moulded to a trapezoidal shape and are made endless. These are particularly suitable for short drives. The included angle for the V-belt is usually from 30° to 40°.

2 - Question

The V-belts are particularly suitable for _____________ drives.
a) short
b) long
c) medium
d) none of the mentioned

Explanation: The V-belts are made of fabric and cords moulded in rubber and covered with fabric and rubber. These belts are moulded to a trapezoidal shape and are made endless. These are particularly suitable for short drives.

3 - Question

The groove angle of the pulley for V-belt drive is usually
a) 20° – 25°
b) 25° – 32°
c) 32° – 38°
d) 38° – 45°

Explanation: A small groove angle will require more force to pull the belt out of the groove which will result in loss of power and excessive belt wear due to friction and heat. Hence the selected groove angle is a compromise between the two. Usually the groove angles of 32° to 38° are used.

4 - Question

A V-belt designated by A-914-50 denotes
a) a standard belt
b) an oversize belt
c) an undersize belt
d) none of the mentioned

Explanation: a V-belt marked A – 914 – 50 denotes a standard belt of inside length 914 mm and a pitch length 950 mm. A belt marked A – 914 – 52 denotes an oversize belt by an amount of (52 – 50) = 2 units of grade number.

5 - Question

The wire ropes make contact at
a) bottom of groove of the pulley
b) sides of groove of the pulley
c) sides and bottom of groove of the pulley
d) any where in the groove of the pulley

Explanation: The wire ropes run on grooved pulleys but they rest on the bottom of the grooves and are not wedged between the sides of the grooves.

6 - Question

Which of the following statements are correct regarding power transmission through V-belts?
(i) V-belts are used at the high-speed end.
(ii) V-belts are used at the low-speed end.
(iii) V-belts are of standard lengths.
(iv) V-angles of pulleys and belts are standardized.
Select the correct answer using the code given below.
a) 1 and 3 only
b) 2 and 4 only
c) 2, 3 and 4
d) 1, 3 and 4

V-belts are used at the high-speed end.
(i) V-belts are used at the high-speed end.
(ii) V-belts are of standard lengths.
(iii) V-angles of pulleys and belts are standardized

7 - Question

The creep in a belt drive is due to the
a) material of the pulleys
b) material of the belt
c) unequal size of the pulleys
d) unequal tension in tight and slack sides of the belt

Explanation: The belt always has an initial tension when installed over the pulleys. This initial tension is same throughout the belt length when there is no motion. During rotation of the drive, tight side tension is higher than the initial tension and slack side tension is lower than the initial tension.

8 - Question

In order to have a good grip on the pulley, the V-belt should touch the bottom of the groove in the pulley.
a) True
b) False