Q. The kinetic energy of a body becomes four times its initial value. The new momentum will be
A) Same as the initial value
B) Twice the initial value
C) Thrice the initial value
D) Half of its initial value
Explanation
(b) Kinetic energy of a body
$K = \frac{P^{2}}{2M}$
Or $K \propto P^{2}$
Or $\frac{{\ p}_{2}}{p_{1}} = \sqrt{\frac{K_{2}}{K_{1}}}\ = \sqrt{4}$
$\ or\ \ P_{2} = 2P_{1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.