Friction

Q. Why does the static friction have greater value than the kinetic friction

Q.

Is Friction A Self Adjusting Force?

Q.

Friction is a force which always opposes the motion.

1. True

2. False

Q.

What is the nature of work done by frictional force?

Q.

________is a force, which always opposes the motion of one body over the other body in contact with it

Q.

Objects moving in fluids must have special shapes. Why?

Q.

Will force of friction come into play when a raindrop rolls down a glass window pane?

Q. Which of the following factors affect the fluid friction?

1. Speed of the object
2. Nature of the fluid
3. Shape of the object
4. All of the above

Q.

The rear of buses and trucks are provided with double wheels or even more. This is provided in order to:

1. Increase force on the ground

2. Increase pressure on the tyres

3. Reduce friction

4. Increase friction for efficient braking

Q.

A meteor burns when it enters the earth atmosphere. This is due to the fact that:

1. Gravitational pull

2. Frictional force

3. Magnetic force

4. None of these

Q. What is the direction of the frictional force acting on the $5kg$ block shown below?

1. Towards left
2. Towards right
3. Upwards
4. Downwards

Q.

Look at the figure given below:

Without which of the following forces given below, the person would not be able to climb the wall?

1. Magnetic force

2. Gravitational force

3. Nuclear force

4. Frictional force

Q. Which of the following statements define friction appropriately?

1. A force that resists the motion of surfaces.
2. A force that resists the relative motion of surfaces.
3. A force that does not depend on the nature of the surface.
4. A force that is non-contact in nature.

Q.

Which of the following is/are true about the frictional force?

1. It acts between all moving objects.

2. It always opposes relative motion between two objects.

3. It is a contact force.

4. It is a non- contact force.

1. 1, 3 and 4

2. 1 and 3

3. 2, 3 and 4

4. All of the above

Q.

What is static friction? [1 MARK]

Q.

If a body is pushed along a surface, it comes to rest after travelling some distance. The______force is responsible for stopping the motion of the body.

1. frictional

2. gravitational

3. magnetic

4. muscular

Q.

Question 9
Give various examples to show that friction is both a friend and a foe.

Q.

Why does a driver increase the speed or velocity of his car on approaching a hilly road?

Q. When a person walks on a rough surface, the frictional force exerted by the surface on the person is opposite to the direction of his motion.

1. True
2. False

Q.

Fluid friction depends upon:

1. Speed of the object in the fluid.

2. The shape of the object moving in the fluid

3. Nature of fluids in which object is moving.

4. All of the above

Q. <!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Give scientific reason .
Powder is sprinkled on a carrom board.

Q. During the padding of a bicycle, the force of friction exerted by the ground on the two wheels is such that it acts

1. In the backward direction on the front wheel and in the forward direction on the rear wheel
2. In the forward direction on the front wheel and in the backward direction on the rear wheel
3. In the backward direction on both the front and the rear wheels
4. In the forward direction on both the front and the rear wheels

Q. What is the direction of force of friction acting on a body moving on a fixed surface?

1. Along the direction of motion
2. Opposite to the direction of motion
3. It has no direction
4. At an angle to the direction of motion

Q.

A plastic ball is rolled along a horizontal surface. The ball comes to stop after some time. Which force is responsible for stopping the motion of the ball?

1. Gravitational pull

2. Frictional force

3. All of these

4. Air resistance

Q. When the boric powder is sprinkled on the carrom board, friction between coins and carrom board decreases.

1. False
2. True

Q.

Friction opposes the _____________ between the surfaces in contact with each other.

Q. Identify the correct sequence of events that take place when an external force acts on a block (at rest) kept on a rough surface.

1. The block starts moving.
2. Static friction starts acting on the block.
3. Kinetic friction acts on the block.
4. The block continues to be stationary.

Q.

Which of the following forces is necessary to cause horizontal movement of a person on the ground?

1. Friction

2. We can walk without any force

3. Normal force

4. Weight

Q. Question 13
Imagine that an object is falling through a long straight glass tube held vertical; air has been removed completely from the tube. The object does not touch the walls of the tube. Will the object experience any force of friction?

Q. When we stop pedaling our bicycle, it slows down and gradually comes to rest. Which of the following forces is responsible for this?

1. Muscular force
2. Force of friction
3. Electrostatic force
4. The system cannot remains in equilibrium