Kinetic friction is the
Kinetic friction is defined as a force that acts between moving surfaces. A body moving on the surface experiences a force in the opposite direction of its movement. The magnitude of the force will depend on the coefficient of kinetic friction between the two materials.
There are three types of friction:
| Static friction | Kinetic friction/sliding friction | Rolling friction |
| The friction that exists between an object at rest and a rough surface on which it is placed, such friction is termed as static friction. | The friction between the two surfaces when there is a relative motion between the surfaces then it is called kinetic friction. | When a block is rolling (usually a circular body like a ball, tire) on a surface then the friction acting is called rolling friction. |
| The coefficient of friction due to this friction is called a static friction coefficient. | The coefficient of friction due to this friction is called a kinetic friction coefficient. | The coefficient of friction due to this friction is called a rolling friction coefficient. |