A marble going at a speed of `2 ms^(-1)` hits another marble of equal mass at rest. If the collision is perfectly elastic, then the velocity of the first marble after collision is

Options

A. `4 ms^(-1)`
B. `0 ms^(-1)`
C. `2 ms^(-1)`
D. `3 ms^(-1)`

Answer

B

Explanation

`vecv_(1)=((m_(1)-m_(2))/(m_(1)+m_(2)))vecu_(1)+((2m_(2))/(m_(1)+m_(2))) vecu_(2)`.