Question

A ball is dropped from a height, of 20 m . If coefficient of restitution is 0.5. The ball rebounds to a height of

• A. 5 m
• B. 10 m
• C. 20 m
• D. 2.5 m

Answer 1

Answer: (A)

5 m

Given,

Height $\left(h\right)$ of the ball dropped is $20m$

coefficient of restitution$\left(e\right)$ is $0.5$

Height after ball rebound that means we have to find out first collision after ball dropped.

We know that

Height after first collision is ,

$h^{{}^{\prime }}=e^{2}h$

Substitute value of height and coefficient of restriction in above equation

$h^{{}^{\prime }}={\left(0.5\right)}^2\times 20h^{{}^{\prime }}=5m$

Hence, correct option is $\left(A\right)$