A ball falls on the ground from a height of 2.0 m and rebounds up to a height of 1.5 m.Find the coefficient of restitution.

$u=\sqrt{2gh}$

= velocity on the ground when ball approaches the ground

$\Rightarrow u=\sqrt{2\times 9.8\times 2}$

v=velocity of ball when it separates from the ground

v=eu

$v=\sqrt{2g{h}_2}$

$=\sqrt{2\times 9.8\times 1.5}$

or $e=\frac{\sqrt{2\times 9.8\times 1.5}}{\sqrt{2\times 9.8\times 2}}=\frac{\sqrt{3}}{2}$