The kinetic energy of a light body and a heavy body is same. Which one of the following statements is CORRECT?
The kinetic energy of a light body and a heavy body is same. Which one of the following statements is CORRECT?
The light body has greater momentum.
A body having high velocity has greater momentum.
Both bodies have same momentum.
The heavy body has greater momentum.
Solution
Kinetic energy,
$\mathrm{k}=\frac{1}{2} \mathrm{mv}^{2}=\frac{(\mathrm{mv})^{2}}{2 \mathrm{~m}}=\frac{\mathrm{p}^{2}}{2 \mathrm{~m}}$
or $\mathrm{p}=\sqrt{2 \mathrm{mk}}$ i.e., $\mathrm{p} \propto=\sqrt{\mathrm{m}}$
Thus the heavier body has a greater momentum than the lighter one.