Q. Escape velocity on the surface of earth is $11.2\ km/s$. Escape velocity from a planet whose mass is the same as that of earth and radius 1/4 that of earth is
A) $2.8\ km/s$
B) $15.6\ km/s$
C) $22.4\ km/s$
D) $44.8\ km/s$
Explanation
(c) $v_{e} \propto \frac{1}{\sqrt{R}}$. If $R$ becomes $\frac{1}{4}$ then $v_{e}$ will be 2 times
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.