A rubber ball is dropped from a height of $5 \,m$ on a planet where the acceleration due to gravity is not known. On bouncing, it rises to $1.8\, m$. The ball loses its velocity on bouncing by a factor of
A rubber ball is dropped from a height of $5 \,m$ on a planet where the acceleration due to gravity is not known. On bouncing, it rises to $1.8\, m$. The ball loses its velocity on bouncing by a factor of
$16/25$
$2/5$
$3/5$
$9/25$
A rubber ball is dropped from a height of $5 \,m$ on a planet where the acceleration due to gravity is not known. On bouncing, it rises to $1.8\, m$. The ball loses its velocity on bouncing by a factor of
If ball falls from height ${h_1}$ and bounces back up to height ${h_2}$ then $e = \sqrt {\frac{{{h_2}}}{{{h_1}}}} $
Similarly if the velocity of ball before and after collision are ${v_1}$ and ${v_2}$ respectively then $e = \frac{{{v_2}}}{{{v_1}}}$
So $\frac{{{v_2}}}{{{v_1}}} = \sqrt {\frac{{{h_2}}}{{{h_1}}}} = \sqrt {\frac{{1.8}}{5}} = \sqrt {\frac{9}{{25}}} = \frac{3}{5}$
i.e. fractional loss in velocity $ = 1 - \frac{{{v_2}}}{{{v_1}}} = 1 - \frac{3}{5} = \frac{2}{5}$
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