Question

state the emprical laws of static and kinetic friction

Answer 1

When an object is moving, the friction is proportional and perpendicular to the normal force (N)

Friction is independent of the area of contact so long as there is an area of contact.

The coefficient of static friction is slightly greater than the coefficient of kinetic friction.

Within rather large limits, kinetic friction is independent of velocity.

Friction depends upon the nature of the surfaces in contact.