A ball of mass 12 kg is released from a height of 2.5 m find the gravitational potential energy of the ball at point A
and when it reach the ground.
then deduce the kinetic energy of the ball once it reach the ground
(use g=10 N/kg) * 5

300 J

Explanation:

From conservation of energy;

Gravitational potential energy at top = Kinetic Energy at bottom

mgh = ½mv²

We are given;

Mass; m = 12 kg.

Height; h = 2.5 m

g = 10 m/s²

Thus;

mgh = 12 × 2.5 × 10 = 300 J

Since mgh = Kinetic Energy at bottom.

Thus; kinetic energy of the ball once it reach the ground = 300 J

if the person is shown to have +90n, then ans is -10n.

if the person is shown to have -90n, then ans is +10n.