Q112 / 200 · NEET 2022 (Phase 1) · Physics

The 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

Solution

For a thin uniform disc.

Radius of gyration

Case 1: $K_{1} = \frac{R}{\sqrt{2}}$

Case 2: $K_{2} = \frac{R}{2}$

$Q \Rightarrow \frac{K_{1}}{K_{2}} = ?$

$∴ \frac{K_{1}}{K_{2}} = \frac{\frac{R}{\sqrt{2}}}{\frac{R}{2}}$ $= \sqrt{2}$

Hence, the correct answer is option: 'A'.