Q. Two balls of masses 2 g and 6 g are moving with KE in the ratio of 3:1. What is the ratio of their linear momenta?
A) 1:1
B) 2:1
C) 1:2
D) None of these
Explanation
(a) Kinetic energy$,k = \frac{1}{2}mv^{2}$
$= \frac{1}{2} \times \frac{m\left( mv^{2} \right)}{m}$
$= \frac{\left( mv^{2} \right)}{2m}ork = \frac{p^{2}}{2m}$
$= \ \frac{k_{1}}{k_{2}} = \frac{p_{1}^{2}}{2m_{1}} \times \frac{2m_{2}}{p_{2}^{2}}\frac{3}{1}$
=$\frac{p_{1}^{2}}{p_{2}^{2}} \times \frac{6}{2}$
$p_{1}:p_{2} = 1:1\ $
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.