1. The problem statement, all variables and given/known data Show that the center of mass of a uniform semicircular disk of radius R is at a point 4R/(3(pi)) from the center of the circle. 2. Relevant equations Total mass Center of mass = M rcm = m1r1 + m2r2 + ... 3. The attempt at a solution I do not know how to apply integration to this problem to find the center of mass. Help, please?