Q. A ball dropped from a height of 2 m rebounds to a height of 1.5 m after hitting the ground. Then the percentage of energy lost is
A) 25
B) 30
C) 50
D) 100
Explanation
(a) Percentage of energy loss
=$\frac{mg(2 - 1.5)}{mgh} \times 100$
$= \frac{mg(0.5)}{mg \times 2}\ \times 100$
=25%
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.