What is the difference between elastic and inelastic collisions in momentum terms?

In elastic collisions, both momentum and kinetic energy are conserved, while in inelastic collisions, only momentum is conserved.

In physics, collisions are categorised into two types: elastic and inelastic. An elastic collision is one in which both momentum and kinetic energy are conserved. This means that the total momentum and total kinetic energy before the collision are equal to the total momentum and total kinetic energy after the collision. This type of collision is common in ideal situations, such as interactions between gas molecules or subatomic particles.

On the other hand, an inelastic collision is one in which only momentum is conserved, but kinetic energy is not. The total momentum before the collision is still equal to the total momentum after the collision. However, the total kinetic energy before the collision is not equal to the total kinetic energy after the collision. Some of the kinetic energy is transformed into other forms of energy, such as heat or sound. This type of collision is common in everyday situations, such as a car crash or a bouncing ball.

In terms of momentum, both types of collisions obey the law of conservation of momentum. This law states that the total momentum of a system of objects is constant, provided that no external forces are acting on it. However, the key difference lies in the conservation of kinetic energy. In an elastic collision, the objects 'bounce' off each other without loss of speed or kinetic energy. In an inelastic collision, the objects may stick together or deform, and some kinetic energy is lost as heat, sound or other forms of energy. This is why inelastic collisions are often less 'bouncy' than elastic ones.