A heavy steel ball of mass greater than 1 kg moving with a speed of 2 m `sec^(-1)` collides head on with a stationary ping-pong ball of mass less than 0.1 gm. The collision is elastic. After the collision the ping-pong ball moes approximately with speed

Options

A. `2m sec^(-1)`
B. `4m sec^(-1)`
C. `2xx10^(4)msec^(-1)`
D. `2xx10^(3) m sec^(-1)`

Answer

B

Explanation

We know that when heavier body strikes elastically with a lighter body then after collision lighter body will move with double velocity that of heavier body.
i.e the ping pong ball move with speed of `2 xx 2= 4m//s`