A circular disc of mass M and radius R is rotating about its axis with angular speed If about another stationary disc having radius `omega_1`.
`R/2` and same mass M is dropped co- axially on to the rotating disc. Gradually both discs attain constant angular speed `omega_2`. The energy lost in the process is p% of the initial energy . Value of p is ........

A solid cylinder of mass M and radius R rotates about its axis with angular speed omega . Its rotational kinetic energy is

A solid cylinder of mass M and radius R rotates about its axis with angular speed omega . Its rotational kinetic energy is

A disc of mass 2 Kg and radius 1 m rotates about its own axis with and angular speed 60 rpm. Find its kinetic energy and angular momentum .

A disc of moment of inertia la is rotating in a horizontal plane about its symmetry axis with constant angular speed co. Another discinitially at rest of moment of inertia I, is dropped coaxially on to the rotating disc. Then, both the discs rotate with same constant angular speed The loss of kinetic energy due to friction in this process is,

A thin circular disc of mass 12 kg and radius 0.5 m rotates with an angular velocity of 100 rad/s. The rotational kinetic energy of the disc is

A circular disc of moment of inertia I_(1) is rotating in a horizontal plane, about its symmetry axis, with a constant angular speed omega_(1) . Another disc of moment of inertia I_(2) is placed coaxially on the rotating disc. Initially the second disc has zero angular speed. Eventually both the discs rotate with a constant angular speed omega_(2) . The energy lost by the initially rotating disc to friction is ............