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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, M1R1 = M2R2. In the light of the above statements, choose the most appropriate answer from the options given below : (1) Both A and R are correct but R is NOT the correct explanation of A (2) A is correct but R is not correct (3) Both A and R are correct and R is the correct explanation of A (4) A is not correct but R is correct

1. Both A and R are correct but R is NOT the correct explanation of A
2. A is correct but R is not correct
3. Both A and R are correct and R is the correct explanation of A
4. A is not correct but R is correct

Correct answer: A is not correct but R is correct

Solution

The assertion is incorrect because escape velocity depends on both mass and radius, and if two planets have the same escape velocity, their mass and radius must be related in a specific way. The reason is correct as it highlights the relationship between mass and radius, but it does not support the assertion.

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