A uniform, solid sphere of mass 3.2 kg and diameter 63 cm is rotating about its diameter at 230 rev/min. What is the kinetic energy of rotation? 230rev/min= 24.1 rad/s I know that KE=1/2Iw^2 and interia of a solid sphere is I=2/5MR^2 I=(2/5)(3.2)(.63)^2 =.508032 KE=(1/2)(.508032)(24.1)^2 =147.5 J For some reason my answer is wrong. Am I missing something? What am I doing wrong?