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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 : A spherical body of radius (5 ± 0.1) mm having a particular density is falling through a liquid of constant density. The percentage error in the calculation of its terminal velocity is 4%. Reason R : The terminal velocity of the spherical body falling through the liquid is inversely proportional to its radius. In the light of the above statements, choose the correct answer from the options given below

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

Correct answer: A is true but R is false

Solution

The assertion is true because the percentage error in terminal velocity can be calculated based on the radius and density, while the reason is false since terminal velocity is actually proportional to the square of the radius, not inversely.

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