Question

A ball is dropped from 30 m on hitting the ground if it loses 40% of its energy. It rebounds to a height equal to
1) 12m 2) 15m 3) 16m 4) 18m

Answer 1

Explanation:

The potential energy of gravity is directly affected by the height. when the ball is dropped from a 10m height, it loses 40% energy thus affecting the same percentage of height when it bounces back. Now 40% of the energy lost means 40% of the height also lost and bouncing back.