Question

A disc of moment of inertia is rotating in a horizontal plane about an axis passing through a center and perpendicular to its plane with constant angular speed ω. Another disc of moment of inertia having zero angular speed is gently placed coaxially on a rotating disc. Now both discs are rotating with constant angular speed ω. The energy lost in the process is:______

Answer 1

The energy lost in the process of placing a disc of moment of inertia on a rotating disc can be calculated using the principle of conservation of angular momentum. The percentage of energy lost can be determined by dividing the energy lost by the initial kinetic energy of the rotating disc and multiplying by 100.

Step-by-step explanation:

The energy lost in the process of placing a disc of moment of inertia on a rotating disc can be calculated using the principle of conservation of angular momentum.

When the second disc is placed on the rotating disc, the initial angular momentum of the system remains constant. However, some of the initial kinetic energy of the system is lost to friction. This energy lost can be calculated by subtracting the final rotational kinetic energy of the combined discs from the initial rotational kinetic energy of the rotating disc.

The percentage of energy lost can be determined by dividing the energy lost by the initial kinetic energy of the rotating disc and multiplying by 100.