The grooved drums in the two systems shown are identical. In both cases, (a) and (b), the system's at rest at time t=0. Determine the angular velocity of each grooved

drum at time t= 4 s.Neglect friction at the pivot O. The disk has a mass of 14 kg and a radius of gyration about O of225 mm. The distance r, is 325 mm and the distance r, is 215 mm.