JEE Main Physics question
The moment of inertia of a solid sphere about an axis passing through its centre of gravity is . Then its radius of gyration about a parallel axis at a distance from the first axis is
Answer: (B)
Solution
I = I_{cm}+M(2R)^2 = \dfrac25MR^2+4MR^2=\dfrac{22}{5}MR^2 = MK^2 \Rightarrow K=\sqrt{\dfrac{22}{5}}\,R.