A ball is dropped from height 'H' onto a horizontal surface. If the coefficient of restitution is 'e' then the total time after which it comes to rest is

Options

A. `sqrt((2H)/(g))((1 -e)/(1+e))`
B. `sqrt((2H)/(g))((1 +e)/(1-e))`
C. `sqrt((2H)/(g))((1 +e^(2))/(1-e^(2)))`
D. `sqrt((2H)/(g))((1 -e^(2))/(1+e^(2)))`

Answer

B

Explanation

`t = sqrt((2h)/(g)) + 2 sqrt((2h_(1))/(g)) + 2 sqrt((2h_(2))/(g)) + -- and h_(n) = e^(2n) h`.