JEE Mains · Physics · STD 11 - Gravitation
- JEE Mains 2025
- Easy
- MCQ
Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) : A simple pendulum is taken to a planet of mass and radius, 4 times and 2 times, respectively, than the Earth. The time period of the pendulum remains same on earth and the planet.
Reason (R): The mass of the pendulum remains unchanged at Earth and the other planet.
In the light of the above statements, choose the correct answer from the options given below :
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
Step-by-step Solution
Detailed explanation
\(\begin{aligned}
& g=\frac{G M}{R^2} \\
& g^{\prime}=\frac{G(4 M)}{(2 R)^2}=g
\end{aligned}\)
A is correct, \(R\) is correct ; but since \(T=2 \pi \sqrt{\frac{\ell}{g}}\) doesn't depend on mass ; R doesn't explain A .
& g=\frac{G M}{R^2} \\
& g^{\prime}=\frac{G(4 M)}{(2 R)^2}=g
\end{aligned}\)
A is correct, \(R\) is correct ; but since \(T=2 \pi \sqrt{\frac{\ell}{g}}\) doesn't depend on mass ; R doesn't explain A .
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