Rolling Friction

Q.

Explain why the sliding friction is less than the static friction.

Q.

Explain how friction can be increased and decreased?

Q.

When static, sliding and rolling frictional forces are to be arranged in an increasing order, which one of the following options would be correct?

1. Rolling friction < Sliding friction < Static friction

2. Static friction < Sliding friction < Rolling friction

3. Sliding friction < Static friction < Rolling friction

4. Rolling friction < Static friction < Sliding friction

Q.

Give two examples of desirable force of friction

Q.

Which of the following statements is incorrect?
(a) static friction is greater than rolling friction
(b) sliding friction is less than rolling friction
(c) rolling friction is less than static friction
(d) static friction is greater than sliding friction

Q.

What are the effects of normal force on friction

Q.

Arrange the following in descending order of magnitude: (i) static friction (ii) sliding friction (iii) rolling friction.

Q.

How do we measure friction?

Q.

It is easier to drag a wheel than to roll it.

1. False

2. True

Q. When you accelerate your bicycle, in which direction the friction will act on the rear wheel?

1. Towards the motion of bicycle
2. Opposite to motion of bicycle
3. Friction doesn’t act
4. Depends upon the mass of the cyclist

Q.

When one body rolls over the surface of another body, the resistance to its motion is called ___ friction.

Q. Four children were asked to arrange forces due to rolling, static and sliding frictions in a decreasing order. Their arrangements are given below. Choose the correct arrangement explaining why.
1st boy - rolling, static, sliding
2nd boy - rolling, sliding, static
3rd boy - static, sliding, rolling
4th boy - sliding, static, rolling
[3 MARKS]

Q.

Since rolling friction is less than sliding friction, sliding friction is replaced with rolling friction in most machines using ball bearings.

1. False

2. True

Q. Choose the correct statement among the following options.

1. Force cannot change the state of motion of a very heavy object.
2. Force can change the shape of an object.
3. Force only changes the speed of a body.
4. Force can change the state of motion of an object only when in contact with it.

Q.

Which type of friction comes into play when a book kept on cylindrical pencils is moved by pushing?

Q. It is difficult to move a cycle with breaks because ____________.

Q.

Why is it convenient to pull a block on a trolley fitted with wheels rather than to drag the box on the floor? [3 MARKS]

Q.

What is sliding friction and rolling friction.

Q.

If the static friction between two surfaces P and Q is measured to be 50N, then the rolling friction between these two surfaces should most likely to be:
(a) 75N
(b) 45N
(c) 55N
(d) 65N

Q. Four cubical boxes are labelled A, B, C, and D. Boxes A and B are placed in a grass field, and boxes C and D are placed on marble floors as shown. Which box requires the maximum force to be moved?

1. Box A
2. Box B
3. Box C
4. Box D

Q.

What is meant by rolling friction?

Q.

Name one example from everyday life where wheels (or rollers) are used to reduce friction.

Q.

Wheels are added to trolleys for smooth travel. What is the principle behind this?

1. Sliding friction is less than rolling friction

2. Sliding friction is more than rolling friction

3. Both sliding friction and rolling friction are the same
4. There is no comparison between sliding friction and rolling friction.

Q.

Which of the following is not a type of friction?

1. sliding

2. static

3. rolling

4. lifting

Q.

Since rolling friction is less than sliding friction, sliding friction is replaced with rolling friction in most machines using ball bearings.

1. True

2. False

Q. Statement 1: Wheels of a moving car will experience both rolling friction and fluid friction simultaneously.

Statement 2: A body cannot experience multiple types of friction at the same time.

1. Only statement 1 is correct
2. Only statement 2 is correct
3. Both statements are correct
4. Both statements are incorrect

Q.

Organize the following types of friction in order from highest to lowest: Sliding friction, static friction, and rolling friction.

Q. Four children were asked to arrange forces due to rolling, static and sliding frictions in a decreasing order. Choose the correct arrangement.

1. 2nd boy -rolling, sliding, static
2. 1st boy - static, rolling, sliding
3. 3rd boy - static, sliding, rolling
4. 4th boy - sliding, static, rolling

Q.

Which of the following is the ascending order of magnitude, for different kinds of friction?

1. Static, sliding, rolling

2. Rolling, sliding, static

3. Static, rolling, sliding

4. Rolling, static, sliding

Q. A ball is undergoing pure rolling on a metal surface. What type of friction is acting on the ball?

1. Rolling friction
2. Fluid friction
3. Static friction
4. Sliding friction