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

`(2)`

Explanation

`vec v_(1) = ((m_(1)- m_(2))/(m_(1) + m_(2)))vec u_(1) + ((2m_(2))/(m_(1) + m_(2))) vec u_(2)`