A particle of mass m moving with velocity `u_(1)` collide elastically with another particle of same mass moving with velocity `u_(2)` in the same direction. After collision their speeds are `v_(1)` and `v_(2)` respectively then
(A) `u_(1)+v_(1)=v_(2)+u_(2)`, (B) `u_(1)-v_(1)=v_(2)+u_(2)`

Options

A. Both the equations A and B are correct
B. Both the equation A and B are incorrect
C. Equation A is correct but not B
D. Equation B is correct but not A

Answer

C

Explanation

Equation A is correct but not B
`e=-((v_(2)-v_(1))/(u_(2)-u_(1)))`
`rArr 1(u_(2)-u_(1))=-(v_(2)-v_(1))`
`rArr u_(2)+v_(2)=u_(1)+v_(1)`