The moment of inertia of a uniform thin rod about a perpendicular axis passing through one end is $\mathrm{l}_{1 .}$. The same rod is bent into a ring and its moment of inertia about a diameter is $\mathrm{I}_{2-}$. If $\frac{I_1}{I_2}$ is $\frac{x \pi^2}{3}$,
