A particle is projected vertically upwards from a point A on the ground. It takes time to reach a point B, but it still continues to move up. If it takes further time to reach the ground from point B. Then height of point B from the ground is :

Answer

D

Explanation

`t_(AC)=(t_(1)+t_(2))/2, t_(BC)=(t_(2)-t_(1))/2`
`:. AB=AC-BC`
`=1/2g ((t_(1)+t_(2))/2)^(2)-1/2g((t_(2)-t_(1))/2)^(2)`
`=1/2g t_(1)t_(2)`