A body is projected with an angle `theta`.The maximum height reached is `h`.If the time of flight is `4 sec` and `g=10m//s^(2)`,then the value of `h` is

Options

A. 40 m
B. 20 m
C. 5 m
D. 10 m

Answer

B

Explanation

As, `t = (2u sin theta)/(g) rArr 4 = (2u sin theta)/(g)` .....(i)

`rArr u sin theta = 2g` and `h = (u^(2) sin^(2)theta)/(2g) = (4g^(2))/(2g)` [from Eq.(i)]
`rArr h = 20 m`