# Angular Velocity and Rotational Energy

A disk of radius .3 meters and mass of .5kg is held over another disk of radius .5 meters and mass 1 kg which is rotating in a horizontal plane at a rate of 15.92 rev/sec. The top disk is released and drops onto the bottom disk (centers align).

a) What is the final angular velocity (in rev/sec) of the two disks?

b) What was the change in rotational energy of the two-disk system?

https://brainmass.com/physics/rotation/angular-velocity-rotational-energy-28666

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Question a)

For the system, the total energy did not change, ...

#### Solution Summary

The solution provides step-by-step calculation for final angular velocity and rotational energy in a two-disk system.

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