NEET-XII-Physics
qstns with ansrs year:2022
- #30The 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 :
(A) `` 1: \sqrt{2} ``
(B) `` 2: 1 ``
(C) `` \sqrt{2}: 1 ``
(D) `` 4: 1 ``digAnsr: CAns :
`` k =\sqrt{\frac{ I }{ m }} ``
`` \Rightarrow \frac{ k _{1}}{ k _{2}}=\sqrt{\frac{ I _{1}}{ I _{2}}} ``
`` =\sqrt{\frac{ mR ^{2} / 2}{ mR ^{2} / 4}}=\sqrt{2}: 1 ``