Give two examples where a body possesses both, kinetic energy and potential energy.

A boy weighing $40 \mathrm{k}\mathrm{g}$ makes a high jump of $1.5 \mathrm{m}$. What is his potential energy at the highest point? $\left(\mathrm{g}=10 \mathrm{m}/{\mathrm{s}}^2\right)$

What type of energy is possessed by the stretched rubber strings of a catapult?

What type of energy is possessed by the piece of stone which is thrown away on releasing the stretched rubber strings of catapult?

A weightlifter is lifting weights of mass $200 \mathrm{k}\mathrm{g}$ up to a height of $2 \text{metres}$. If $\mathrm{g}=9.8 \mathrm{m}{\mathrm{s}}^{-2}$, calculate the work done by the weightlifter.