A body of mass m moving with velocity v collides head-on elastically with another body of mass 2 m which is…

A body of mass m moving with velocity v collides head-on elastically with another body of mass 2m which is initially at rest. The ratio of K.E. of mass m before and after the collision will be

Solution

K.E. of the colliding body before the collision =12mv2
After collision its velocity becomes
v'=m1-m2m1+m2v=m3mv=v3
K.E. after collision 12mv'2=12mv29
The ratio of kinetic energy =K.EbeforeK.Eafter=12mv212mv29=9:1

Asked in: Practice

Practice more Center of Mass Momentum and Collision questions on Aicharya