MCQ
A ball is dropped from height $5\,\,m$. The time after which ball stops rebounding if coefficient of restitution between ball and ground $e = 1/2$, is ............. $\mathrm{sec}$
- A$1$
- B$2$
- ✓$3$
- Dinfinite
✓
Answer
Correct option: C.
$3$
c
$t=\frac{u}{g} \propto e \Rightarrow t \sqrt{\frac{2 h}{g}}\left[1+2\left(e+e^{2}+e^{3}+\ldots \infty\right)\right]=3 s$
$t=\frac{u}{g} \propto e \Rightarrow t \sqrt{\frac{2 h}{g}}\left[1+2\left(e+e^{2}+e^{3}+\ldots \infty\right)\right]=3 s$
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