The radius of gyration of a circular disc of radius $R$ and mass $m$ rotating about its diameter as an axis is:

The ratio of the radii of two solid spheres of same mass is $2:3$. The ratio of the moments of inertia of the spheres about their diameters is

$A$ circular disc has radius $R_1$ and thickness $T_1$. Another circular disc made of the same material has radius $R_2$ and thickness $T_2$. If the moment of inertia of both discs are same and $\frac{R_1}{R_2}=2$, then $\frac{T_1}{T_2}=\frac{1}{\alpha}$. The value of $\alpha$ is . . . . . . .

Two circular discs of iron have the same thickness. The diameter of disc $A$ is twice that of disc $B$. The moment of inertia of $A$ will be ........ times that of $B$.

The figure shows a triangular lamina which can rotate about different axes. The moment of inertia is maximum about the axis:

The figure shows two solid discs with radius $R$ and $r$ respectively. If the mass per unit area is the same for both,what is the ratio of the moment of inertia $(MI)$ of the bigger disc about axis $AB$ (which is perpendicular to the plane of the disc and passing through its centre) to the $MI$ of the smaller disc about one of its diameters lying on its plane? Given $M$ is the mass of the larger disc.