If coefficient of restitution be 0.5, percentage loss of energy on each rebounding of a ball dropped

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5.Work, Energy, Power and Collision

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If the coefficient of restitution be $0.5,$ what is the percentage loss of energy on each rebounding of a ball dropped from a height ............ $\%$

A

$12.5$

B

$25$

C

$50$

D

$75$

Solution

$\%$ change in $\mathrm{K} \mathrm{E}=\frac{\Delta \mathrm{K}}{\mathrm{k}_{\mathrm{i}}} \times 100 \%$

$=\left[\left(\frac{\mathrm{v}_{\mathrm{f}}}{\mathrm{v}_{\mathrm{c}}}\right)^{2}-1\right] \times 100 \%$

$=\left(e^{2}-1\right) \times 100 \%$

$=-75 \%(75 \%$ loss)

Standard 11

Physics

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