Physical Science:

Momentum conservation is very useful in collision problems because the collision force is internal and hence does not change the total momentum. The impulse of a collision is the total momentum transferred during the collision, where a collision is an event where a very large force is exerted over a body for a very short interval of time, \(\Delta t\text{.}\) During that interval magnitude of force is continuously changing. Therefore, the impulse of a force is the product of the average force and the time interval during the contact.

Collision provides a way to better understand the motion. A collision is an interaction between two objects that may or may not have made physical contact. In a collision the colliding objects experience a pair of forces acting on them. The direction of the force on the first object is opposite to the direction of the force on the second object and these forces are equal in magnitude. These forces are Newton’s III law pair. In an isolated system, total momentum is always conserved, hence such forces often increase the momentum of one object and decrease the momentum of the other. There are two kinds of collisions, elastic collision and inelastic collision. Elastic collision: objects are not deformed, e.g. bouncing balls, car’s bumper, etc. Inelastic collision: objects become permanently deformed, e.g. auto accidents, throwing a mud on wall. Kinetic energy is only conserved in an elastic collission but not in an inelastic collision. However, momentum is conseved in both types of collisions. Total energy remains conserved in both types of collision.