Question

If the energy of a ball falling from a height of 10 meters is reduced by 40% how high will it rebound?

Answer 1

Given,

Initial height of ball, $h=10m$

Potential energy$=mgh$

Reduce potential energy = $mg{h}_{new}$

$mg{h}_{new}=\left(\frac{100-40}{100}\right)mgh$

$h_{new}=0.6\times 10=6m$

Hence, height after rebound is $6m$