Two thin discs, each of mass M and radius r meter, are attached as shown in the figure, to form a rigid body. The rotational inertia of this body about an axis perpendicular
to the plane of disc B passing through its center is
Moment of inertia of discs A and B about the axis through their center of mass and perpendicular to the plane will be
Now, moment of inertia of disc A about an axis through B, by theorem of parallel axis will be