A small ball with mass 2.50 kg is mounted on one end of a rod 0.750 m long and of negligible mass. The system rotates in a horizontal circle about the other end of the rod at 5040 rev/min.
(a) Calculate the rotational inertia of the system about the axis of rotation.
1 kg·m2
(b) There is an air drag of 3.00 10-2 N on the ball, directed opposite its motion. What torque must be applied to the system to keep it rotating at constant speed?
2 N·m