Q. A spacecraft of mass $M$ is moving with velocity $v$ in free space when it explodes and breaks in two. After the explosion, a mass $m$ of the spacecraft is left stationary. What is the velocity of other part?
A) $\frac{Mv}{(M - m)}$
B) $\frac{mv}{(M + m)}$
C) $\frac{mv}{(M - m)}$
D) $\frac{(M + m)v}{M}$
Explanation
(a) From conservation of momentum
$Mv = m \times 0 + (M - m)v^{'} \Rightarrow v^{'} = \frac{Mv}{(M - m)}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.