Ball bearing is a device which usually converts:

The frictional force exerted by a fluid is called:

A person has applied some mustard oil on his hands. Which of the following objects will become most difficult for him to hold in his hand?

When a pencil cell is released from a certain point on an inclined wooden board, it travels a distance of 35 cm on floor A before it comes to rest. When the same pencil cell is released from the same point on the same inclined board, it travels a distance of 20 cm on floor B before coming to rest. Which floor, A or B, offers greater friction? Give reason for your answer.

A car is moving towards North. What will be the direction of force of friction acting on this car due to surface of road ?