Question

2
A sphere of mass m is moving with a velocity u and
makes a head on collision with another identical mass
which is at rest. It is observed that the stationary mass
starts moving with a lesser velocity than u, after the
collision
a) Which physical quantity is conserved here?
b) Define coefficient of restitution.
c) Determine the ratio of the velocities of the two
spheres after elastic collision if 'e' is the coeffi-
cient of restitution.​

Answer 1

Explanation:

1: the collision is elastic then momentum and kinetic energy both are conserved but if it is inelastic then momentum is conserved

2:coefficient of restitution is defined as ratio of velocity of separation (V-v)to velocity of approach(U-u)

e=V-v/U-u

sorry I can only answer the two points