A uniform solid disk of radius R and mass M is free to rotate on a frictionless pivot through a point on its rim (Fig. P10.57). If the disk is released from rest in the position shown by the coppercolored circle,
(a) what is the speed of its center of mass when the disk reaches the position indicated by the dashed circle?
(b) What is the speed of the lowest point on the disk in the dashed position?
(c) What If? Repeat part (a) using a uniform hoop