Which of the following is not true about Frictional force?

A

Friction is the force which opposes the relative motion of two surfaces in contact.

B

The force of friction that acts when a body is moving (sliding) on a surface is called sliding friction.

C

Friction in machines wastes energy and also causes wear and tear.

D

Rolling friction is much more than sliding friction, the use of ball bearings in a machine considerably reduces friction.