Question

What will be the velocity of the stone on reaching the ground? (Take g=10 m s^-2)

Answer 1

Let 'v' be the velocity on reaching the ground.

Using the third equation of motion,

v² - u² = 2gH

or, v²  -  0 = 2(10) (80)

or, v² = 1600

or, v = 40 m/s