A ball is drpped from rest at height `4h`. After it has fallen a distance `d`, a second ball is dropped from rest at height `h`. What should `d` be (in terms of `h`) so that the balls hit the ground at the same time?

Options

A. `d=(3H)/2`
B. `d=H/3`
C. `d=H`
D. `d=3H`

Answer

C

Explanation

For the `1^(st)` ball, `4h=("gt"_(1)^(2))/2impliest_(1)=2sqrt((2h)/g)` & For second ball `t_(2)=sqrt((2h)/g)`
also `sqrt((2h)/g)+sqrt((2d)/g)=2sqrt((2h)/g)implies2sqrt(h)=sqrt(d)+sqrt(h)impliesd=h`