Discuss the common and different characteristics of an elastic collision and an inelastic collision.?

Answer 1

In a fully elastic collision the velocity difference of the two bodies is the same after as before. In an inelastic collision the bodies have no velocity difference after collision, so until an external force changes the momentum of one or the other, they move as if joined together although they are not. Both types of collision follow the law of conservation of momentum, but only the fully elastic type conserves energy. Usually the term elastic is understood to refer to the fully elastic type.
Partially elastic collisions are also possible. With these, the post-collision velocity difference is a factor between 0 and 1 (noninclusive), called the coefficient of restitution, times the initial velocity difference.
The post-collision velocity difference in an elastic collision is divided between the two bodies in inverse ratio to their masses. These individual differences are added to the velocity of the system as a whole, which is the total momentum divided by the total mass.