Question

If the KE of a body becomes four times of its initial value, then the new momentum will be more than its initial momentum by:

• A. $50$%
• B. $100$%
• C. $125$%
• D. $150$%

Answer 1

Answer: (B)

$100$%

$\overrightarrow{p}=\sqrt{2m\left(KE\right)}\Rightarrow \frac{p_2}{p_1}\sqrt{\frac{{KE}_2}{{KE}_1}}=\sqrt{\frac{4}{1}}=2\Rightarrow \frac{\Delta p}{p_1}=\frac{p_2-p_1}{p_1}=1$ or $100$%