State the laws of friction.

Explanation

Following are the laws of friction:
i) Friction always opposes the motion.
ii) Friction acts tangentially along the surface of contact.
iii) Force of friction is independent of area of contact of two bodies.
iv) Force of friction depends on the nature of the surfaces in contact.
v) Frictional force is directly proportional to the normal reaction. i. e. `F prop R`.