A computer disk drive spins at 7200 rpm when a brief 30 second power outage occurs. During this time the drive slows down due to friction which provides a constant deceleration, and the drive makes exactly 2200 revolutions (but is not at rest).
A) What is the angular speed (in rad/s) of the drive when the power comes on, after 30s?
B) How much time would be needed for the drive to come to rest?