Two rings of same mass $M$ and radius $R$ are placed such that their centers coincide and their planes are perpendicular to each other. The moment of inertia of the system about an axis passing through the center and perpendicular to any one ring is

Two spheres $A$ and $B$,each of mass $5 \ kg$,are attached to the ends of a light rod of length $1 \ m$. Treating the spheres as point masses,find the ratio of the moment of inertia of the system about an axis passing through $A$ to that about an axis passing through the center of the rod,both axes being perpendicular to the rod.

$A$ circular disc $A$ of radius $r$ is made from an iron plate of thickness $t$ and another circular disc $B$ of radius $4r$ is made from an iron plate of thickness $t/4$. The relation between the moments of inertia $I_A$ and $I_B$ is:

$A$ wire of length $l$ and mass $m$ is bent in the form of a rectangle $ABCD$ with $(AB/BC) = 2$. The moment of inertia of this wire about the side $BC$ is

The radius of gyration of a disc of mass $50 \, g$ and radius $2.5 \, cm$ about an axis passing through its center of gravity and perpendicular to its plane is ....... $cm$.

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.