A boy standing at the top of a tower of (20,m) height drops... | Physics | SolveeIt | Solveeit

Today, August 18

Question

A boy standing at the top of a tower of $20\,m$ height drops a stone. Assuming $g = 10\, ms^{-2},$ the velocity with which it hits the ground is

A

$10.0\,m/s$

B

$20.0\, m/s$

C

$40.0\, m/s$

D

$5.0 \,m/s$

Answer

$20.0\, m/s$

Explanation

Solution

$v =\sqrt{2 \,gh }=\sqrt{2 \times 10 \times 20}$
$=20 \,m / sec$