Physics · 2021
JEE Main · 25 July 2021, Shift 1 · Q15
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R. Assertion A: Moment of inertia of a circular…
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.Assertion A: Moment of inertia of a circular disc of mass 'M' and radius 'R' about X, Y axes (passing through its plane) and Z-axis which is perpendicular to its plane were found to be $\displaystyle \mathrm{I}_x, \mathrm{I}_y$ & $\displaystyle \mathrm{I}_z$ respectively. The respective radii of gyration about all the three axes will be the same.
Reason R: A rigid body making rotational motion has fixed mass and shape.
In the light of the above statements, choose the most appropriate answer from the options given below:
Official answer
(4)
A is not correct but $\displaystyle \mathbf{R}$ is correct.
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.