Friction Force

Q.

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

1. Gravitational force produces heat

2. Frictional force produces heat

3. Magnetic force produces heat

4. Body moving with very high speed produces heat

Q.

When a bicycle moving with a constant velocity travels from a smooth to a rough surface, its speed __________.

1. increases

2. decreases

3. remains the same

4. None of these

Q.

A block is sliding along a horizontal surface. It comes to rest after sometime. Which force is responsible for stopping the block?

1. Magnetic force

2. Nuclear force

3. Electrostatic force

4. Frictional force