Question

A ball of mass $3m$ moving with a velocity $v_0$ collides elastically with a stationary ball of mass $m$. The velocity of ball of mass $m$ is_________

• A. $\frac{3}{2}{v}_0$
• B. $\frac{v_0}{2}$
• C. $3v_0$
• D. $2v_0$

Answer 1

The correct option is A $\frac{3}{2}{v}_0$

For this situation we can write two equations,

One of momentum conservation and second of e.

Let final velocity of ball of mass 3m be x and of stationary ball be y

Then,

3mv${}_0$=3mx+my

And y-x=v${}_0$

Solving we get x=$\frac{3}{2}{v}_0$