A body is projected horizontally from the top of a tall tower with a velocity of `30ms^(-1)`. At time `t_(1)`, its horizontal and vertical components of the velocity are equal and at time `t_(2)`, its horizontal and vertical displacements are equal. Then `t_(2)-t_(1)` is (take, `g=10ms^(-2)`)

Options

A. 1 s
B. 1.5 s
C. 2 s
D. 3 s

Answer

D

Explanation

As per first condition,
`30=10t_(1)`
`t_(1)=3s`
As per second condition,
`30t_(2)=1/2xx10t_(2)^(2)=t_(2)=6s`
`therefore" "t_(2)-t_(1)=3s`