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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) : Time period of a simple pendulum is longer at the top of a mountain than at the base of the mountain. Reason (R) : Time period of a simple pendulum decreases with increasing value of acceleration due to gravity and vice-versa. In the light of the above statements, choose the most appropriate answer from the options given below :
- Both (A) and (R) are true but (R) is not the correct explanation of (A).
- Both (A) and (R) are true and (R) is the correct explanation of (A).
- (A) is true but (R) is false.
- (A) is false but (R) is true.
Correct answer: Both (A) and (R) are true and (R) is the correct explanation of (A).
Solution
The assertion is correct because the time period of a simple pendulum increases at higher altitudes where gravity is weaker. The reason is also true, as the time period decreases with an increase in gravitational acceleration, thus providing a valid explanation for the assertion.
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