8.0 Types of collision

1. Direct collision or head on collision: If the velocities of the colliding bodies just before and after collision are along their common normal, then the collision is known as direct collision.

2. Collision in two dimension: If the velocities of the colliding bodies are not along their common normal. This type of collision is known as collision in two dimension.

3. Oblique collision: It is a special case of collision in two dimension. In oblique collision common normal $(CN)$ of the colliding bodies is inclined with the horizontal.