College Physics (4th Edition)

The correct answer is: (c) $\frac{m}{M+m}$
We can use conservation of momentum to find the ratio: $(M+m)V = mv+M(0)$ $(M+m)V = mv$ $\frac{V}{v} = \frac{m}{M+m}$ The correct answer is: (c) $\frac{m}{M+m}$