Question

The ball of mass 0.4 kg is dropped from some certain height .As it falls through 2 m. The kinetic energy acquired by it is.

Answer 1

$m=0.4kg$ $g=10m/s^2$

Let ball be dropped from some height $h_1$

And it falls $2m$ and new height is $h_2$ so it loses height hence it loses Potential energy.This loss in potential energy goes into kinetic energy.

$So$ $loss$ $in$ $PE=mg(h_1-h_2)$=$mg\left(2\right)=0.4\times 10\times 2=8Joules$

So $KE$ $gained$=$8Joules$