Spinner Bowl

Collisions fall into two categories: elastic and inelastic. Elastic collisions occur when two objects come in contact with each other and are not damaged or misshapen during the collision. An example of elastic collision is two billiard balls colliding: there might be changes in direction, in energy and in speed, but not in the shape or internal state of the balls.

Inelastic collisions are collisions in which at least one of the colliding objects is altered. An example is a collision between two automobiles. The speed of separation in inelastic collision is always lower than the speed of approach. This is because some energy is lost during the collision in the form of heat or sound. In an automobile collision, that energy causes damage to the cars in the crash.