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Physics · PYQ NEET UG 2022
हिन्दीThe ratio of the radius of gyration of a thin uniform disc about an axis passing through its centre and normal to its plane to the radius of gyration of the disc about its diameter is:
Correct answer · Option 4
\( \sqrt{2} : 1 \)
Explanation
Moment of inertia about normal axis through centre is \( I_1 = \frac{MR^2}{2} \Rightarrow k_1 = \frac{R}{\sqrt{2}} \). About diameter \( I_2 = \frac{MR^2}{4} \Rightarrow k_2 = \frac{R}{2} \). The ratio \( \frac{k_1}{k_2} = \frac{2}{\sqrt{2}} = \sqrt{2} : 1 \).
