 # Given below are two statements : one is labelled as Assertion `
Question:

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, $\mathrm{M}_{1} \mathrm{R}_{1}=\mathrm{M}_{2} \mathrm{R}_{2}$

In the light of the above statements, choose the most appropriate answer from the options given below:

1. Both $\mathrm{A}$ and $\mathrm{R}$ are correct but $\mathrm{R}$ is NOT the correct explanation of $\mathrm{A}$

2. $\mathrm{A}$ is correct but $\mathrm{R}$ is not correct

3. Both $A$ and $R$ are correct and $R$ is the correct explanation of $A$

4. $\mathrm{A}$ is not correct but $\mathrm{R}$ is correct

Correct Option: , 2

Solution:

$\mathrm{V}_{\mathrm{e}}=\sqrt{\frac{2 \mathrm{GM}}{\mathrm{R}}}$

$\frac{\mathrm{M}_{1}}{\mathrm{R}_{1}}=\frac{\mathrm{M}_{2}}{\mathrm{R}_{2}}$

$\mathrm{M}_{1} \mathrm{R}_{2}=\mathrm{M}_{2} \mathrm{R}_{1}$

Hence reason $R$ is not correct.