Physics - Rotation Question with Solution | TestHub

A circular disk of moment of inertia $I_t$ is rotating in a horizontal plane, about its symmetry axis, with a constant angular speed ${\omega }_i$. Another disk of moment of inertia $I_b$ is dropped coaxially onto the rotating disk. Initially the second disk has zero angular speed. Eventually both the disks rotate with a constant angular speed ${\omega }_{\mathrm{f}}$. The energy lost by the initially rotating disc due to friction isNEET 2010 (Screening)