Question

A body of mass 10 kg is projected up with a velocity of 19.6 m s${}^{-1}$. Find the potential energy at its highest point.

Answer 1

Given :
Mass of the body, m $=$ 10 kg
Initial velocity, u $=19.6m{s}^{-1}$
Potential energy (P.E.) at highest point $=$?
For this, first we have to find maximum height, h $=$?
The maximum height reached by a body is given by h $=\frac{u^2}{2g}$
$\Rightarrow h\frac{(19.6{)}^2}{2\times 10}=\frac{384.16}{20}=19.208m$
Therefroe, potential energy at maximum height is, P.E. $=$ mgh
$\Rightarrow P.E.=10\times 10\times 19.208=1920.8J$