Question

If the kinetic energy of a body is increased by 300%, its momentum will increase by

• A. 300%
• B. 30%
• C. 10%
• D. 100%

Answer 1

The correct option is D 100%

Kinetic energy $k=\frac{P^2}{2m}$
where, P is momentum and m is mass.
$k_1=k,k_2=k+300$ % of $k=4k$
$\Rightarrow \frac{P_2}{P_1}=\sqrt{\frac{k_2}{k_1}}=\sqrt{\frac{4k}{k}}=2$
$\Rightarrow P_2=P_1+100$% pf $P_1$
Hence, momentum will increase by 100%.