A sphere `A` moving with speed `u` and rotating With angular velocity `omega` makes a head-on elastic collision with an identical stationary sphere `B`. There is no friction between the surfaces of `A` and `B`. Choose the conrrect alternative(s). Disregard gravity.

Options

A. `A` will stop moving but continue to rotate with an angular velocity `omega`
B. `A` will come to rest and stop rotating
C. `B` will move with speed `u` without rotating
D. `B` will move with speed `u` and rotate with an angular velocity `omega`

Answer

A, C, D

Explanation

There will be exchange of linear velocities only. However the two spheres cannot exert torques on each other, as their surfaces are firctionless and the angular velocities of the spheres do not change.