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Physics · PYQ NEET UG 2023
हिन्दीThe ratio of square of radius of gyration of a solid sphere of mass \( M \) and radius \( R \) about its own axis to the square of radius of gyration of the thin hollow sphere of same mass and radius about its axis is :
Correct answer · Option A
\( 3:5 \)
Explanation
Moment of inertia of solid sphere \( I_1 = \frac{2}{5}MR^2 = Mk_1^2 \implies k_1^2 = \frac{2}{5}R^2 \). For thin hollow sphere \( I_2 = \frac{2}{3}MR^2 = Mk_2^2 \implies k_2^2 = \frac{2}{3}R^2 \). Ratio \( k_1^2/k_2^2 = \frac{2/5}{2/3} = \frac{3}{5} \).
