The rate of rotation of a solid disk with a radius of #6 m# and mass of #5 kg# constantly changes from #5 Hz# to #3 Hz#. If the change in rotational frequency occurs over #1 s#, what torque was applied to the disk?
To answer this question, we must first determine the rotational inertia of the disk (also called the moment of inertia), I :
This will be given by
Similar to Newton's second law F = ma, the corresponding relation for rotational motion is:
The change in angular velocity is 2 Hz x 2