Question

A stone is dropped from a height of 20 m.

(i) How long will it take to reach the ground ?

(ii) What will be it's speed when it hits the ground ? ( g = 10 m / s-2 )

Answer 1

Time it takes to the earth = 20 / 10
= 2
It takes 2 seconds to reach the earth.

It's speed = 20 × 10
= 20 m/s