A player throws a ball upwards with an initial speed of `30 m s^(-1)`. How long does the ball take to return to the player's hands? ( Take g = 10 `m s^(-2)`)

Options

A. 30 m
B. 45 m
C. 90 m
D. 100 m

Answer

B

Explanation

Here , `u = 30 ms^(-1) , g = - 10 ms^(-2)`
At the highest point , v = 0
As `v^(2) -u^(2) = 2` gh
`:. 0-(30)^2=2xx(-10)xxh" or " h=(30xx30)/20=45m `