Q 11-07-002NEETNEET 2026Top questionEasy
Two planets $P_1$ and $P_2$ with equal mass have radii $R_1$ and $R_2$, respectively, where $R_2 = \dfrac{R_1}{2}$. The escape speeds of $P_1$ and $P_2$ are $v_1$ and $v_2$, respectively. Then $\dfrac{v_2}{v_1}$ is :
Answer: (C) $\sqrt{2}$
Concept. $v_e = \sqrt{\dfrac{2GM}{R}}$: for equal masses $v_e \propto \dfrac{1}{\sqrt R}$.
Step 1. Ratio. $\dfrac{v_2}{v_1} = \sqrt{\dfrac{R_1}{R_2}} = \sqrt2$.
Answer. $\sqrt2$ (Option C).
Solution by Sreeraj P, M.Sc Physics