Question

A bullet of mass m moving at a speed v hits a ball of mass M kept at rest.A small part having mass 'm' breaks from the ball and sticks to the bullet.The remaining ball is found to move at a speed $v_1$ in the direction of the bullet.Find the velocity of the bullet after the collision.

Answer 1

Mass of the bullet=m

and speed=v

Mass of the ball=M

$m^1$=frictional mass from the ball

Using law of conservation of momentum $mv+0=(m^1+m)v^1+(M-m^1)v_1$

where $v^1$=final velocity of the bullet+fractional mass

$\Rightarrow v^1=\frac{mv-(M-m)v_1}{m+m^1}$