A zero-momentum spinner has a momentum wheel spinning at 5000 rpm. The angular momentum of the wheel is 100 N-m-s.
a) What is the spin rate of the spacecraft if its moment of inertia, Is = 500 kg-m2?
b) What is the moment of inertia of the wheel?
c) If the wheel suddenly stops, what would the spin rate of the satellite be?
d) Assuming the wheel was fixed, how long would it take to get the wheel back up to a speed of 4000 rpm applying a motor torque of 0.1 N-m?
e) What would the new spin rate of the spacecraft be?