Question

2. A ball of mass 5 kg moves with 20 m/sec, it strikes
with another ball af 10 kg that
moves in same direction
with the velocity of 10 m/sec. After collision velocity
of first ball reduces to 8 m/s in the same
direction. Calculate the velocity of second ball.
Is it a elastic collision or inelastic collision ?

​

Answer 1

............ hopenit was helpful

Answer 2

Let their velocities after the collision be v1 

and v2. As we know for elastic collision. 

Relative velocity of approach = relative velocity of separation

10−4=v2−v1⇒6=v2−v1