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Gravitation

JEE Main level, single correct, medium

139 of 223

Question 139 of 223

Given below are two statements : one is labelled as Assertion $A$ and the other is labelled as Reason $R$ .
Assertion $A$ : The escape velocities of planet $A$ and $B$ are same. But $A$ and $B$ are of unequal mass.
Reason $R$ : The product of their mass and radius must be same. ${M}_{1}{R}_{1}={M}_{2}{R}_{2}$ In the light of the above statements, choose the most appropriate answer from the options given below :

Show answer and solution

Answer: (D) $A$ is correct but $R$ is not correct

{V}_{e}=\sqrt{\dfrac{2GM}{R}}

\dfrac{{M}_{1}}{{R}_{1}}=\dfrac{{M}_{2}}{{R}_{2}}

{M}_{1}{R}_{2}={M}_{2}{R}_{1}

Hence reason

R

is not correct.

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JEE Main 2025 Apr 2 Shift 1 question paper

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