The moment of inertia of a thin square plate $PQRS$ of uniform thickness,about an axis passing through the centre '$O$' and perpendicular to the plane of the plate is (where $I_1, I_2, I_3, I_4$ are respectively the moments of inertia about axes $1, 2, 3, 4$ which are in the plane of the plate as shown in the figure):

Two identical solid spheres each of mass $2\,kg$ and radii $10\,cm$ are fixed at the ends of a light rod. The separation between the centres of the spheres is $40\,cm$. The moment of inertia of the system about an axis perpendicular to the rod passing through its middle point is $........... \times 10^{-3}\,kg\,m^2$.

$A$ solid sphere and a disc of same mass $M$ and radius $R$ are kept such that their curved surfaces are in contact and their centers lie along the same horizontal line. The moment of inertia of the two-body system about an axis passing through their point of contact and perpendicular to the plane of the disc is

Four identical uniform solid spheres,each of mass $M$ and radius $R$,are placed touching each other in a line as shown in the figure,with centers $A, B, C, D$. Let $I_A, I_B, I_C,$ and $I_D$ be the moment of inertia of the entire system of four spheres about an axis passing through the center of the respective sphere and perpendicular to the plane containing the centers. The difference $|I_A - I_B|$ is: (in $MR^2$)

Four identical solid spheres each of mass $m$ and radius $a$ are placed with their centres on the four corners of a square of side $b$. The moment of inertia of the system about one side of the square is:

The moment of inertia of a circular disc of radius $2 \,m$ and mass $1 \,kg$ about an axis $XY$ passing through its center of mass and perpendicular to the plane of the disc is $2 \,kg \,m^2$. The moment of inertia about an axis parallel to the axis $XY$ and passing through the edge of the disc is