A uniform solid disk of radius 4.18 m and mass 193 kg is free to rotate on a frictionless pivot through a point on its rim. The acceleration of gravity is 9.8 m/s2 : If the disk is released from rest in the po- sition shown by the solid circle, what is the speed of its center of mass when the disk reaches the position indicated by the dashed circle? Answer in units of m/s. i tried using the conservation of energy equation to solve this problem. 1/2mv^2=mgh i used the diameter of the circle for the h, but i still couldn't find the speed of the center of mass. can anyone help?