Introduction to Power Transmission with Belts, Ropes, Chains, and Gears

What is the purpose of the crowned rim on a pulley in a flat belt drive system?

To increase tension on the belt
To decrease power transmission capacity
To introduce compression on the belt
To help keep the belt running centrally on the pulley rim (correct)

Why are V-belts more advantageous than flat belts in terms of power transmission?

They touch the bottom of the pulley groove
They have a shallower groove
They require more frequent adjustments
They utilize the advantage of the wedge action (correct)

What does the neutral section of a belt represent?

Section with highest compression
Section where both tension and compression are equal
Section with highest tension
Section with no tension or compression (correct)

How is the effective radius of rotation of a pulley calculated for an unstretched belt?

By adding half the belt thickness to the radius of the pulley (D) Signup and view all the answers

What is one advantage of using a multiple V-belt system in comparison to a single V-belt system?

Higher power transmitting capacity (B) Signup and view all the answers

In a V-belt drive system, why does the belt not touch the bottom of the groove on the pulley?

To take advantage of the wedge action (C) Signup and view all the answers

What is the main reason for the sag of the belt being more on the upper side than the lower side?

The tight side being on the upper side. (A) Signup and view all the answers

Why is a crossed-belt drive adopted when the driven pulley needs to rotate in the opposite direction to the driving pulley?

To increase power transmission. (A) Signup and view all the answers

What happens if the belt slips over the pulley?

The belt wears out more quickly. (A) Signup and view all the answers

How does applying a small torque in the clockwise direction to the driving pulley affect the motion of the belt?

It tends to rotate the belt with it. (C) Signup and view all the answers

What does having a crossed-belt drive allow for in comparison to an open-belt drive?

Transmitting more power. (C) Signup and view all the answers

Why is sag on the upper side desirable in certain cases?

To prevent possible slip due to excessive tension on the lower side. (C) Signup and view all the answers

What prevents the pulley from slipping in the given context?

A counter-clockwise frictional force (C) Signup and view all the answers

How does the frictional force in the belt affect the tension?

It increases tension on one end and decreases on the other (D) Signup and view all the answers

What is the relationship between the tangential force on the pulley and the frictional force?

The tangential force is equal to the frictional force (C) Signup and view all the answers

What is the direction of the frictional force on the driven side of the pulley?

Counter-clockwise (B) Signup and view all the answers

What is the velocity ratio in the context of a belt and pulley arrangement?

The ratio of the speed of the driven pulley to the driving pulley (B) Signup and view all the answers

What happens if the tangential force on the pulley exceeds the frictional force?

The belt starts to slip (A) Signup and view all the answers

What is the relationship between the rotational speeds of the driving and driven pulleys?

N1 is equal to N2, neglecting slip and inelasticity (B) Signup and view all the answers

What is the law of belting?

The centre line of the belt must lie in the mid plane of the pulley it approaches (A) Signup and view all the answers

What happens if the belt is operated in the reverse direction on non-parallel shafts?

The belt will be thrown off the pulley (A) Signup and view all the answers

What is the role of guide pulleys in the operation of a belt on non-parallel shafts?

Guide pulleys allow the belt to operate in either direction (D) Signup and view all the answers

What is the significance of the thickness of the belt in the operation of a belt drive?

The thickness of the belt does not affect the operation of the belt drive (A) Signup and view all the answers

What is the role of the law of belting in the operation of a belt on non-parallel shafts?

The law of belting ensures that the centre line of the belt lies in the mid plane of the pulley it approaches (B) Signup and view all the answers

What type of connectors are primarily used when the distance between shafts is large?

Belts and ropes (B) Signup and view all the answers

Which type of drives are not positive, meaning their velocity ratios are not constant?

Belts and ropes (A) Signup and view all the answers

What is the primary cause for power transmission in belts and ropes?

Friction between the belt or rope and the pulley (A) Signup and view all the answers

What happens when the power transmitted by belts or ropes exceeds the force of friction?

The belt or rope slips over the pulley (B) Signup and view all the answers

What is the main purpose of keeping the connecting belt in tension in belt drives?

To prevent slipping between the belt and pulley (C) Signup and view all the answers

How can the speed of the driven shaft be varied in belt drives?

By varying the diameters of the two pulleys (C) Signup and view all the answers