1. A hollow sphere starts from rest and makes 125 revolutions about an axis through the center of mass in two minutes before reaching a final angular speed. The sphere has a mass of 3.10 kg and a radius of 14.0 cm. (20) inital velocity=0 a) Determine the angular acceleration of the mass, assuming a constant acceleration. (5) 2 W= wo + zao w=0 2 a = wf - w WE Wi 20 20 27.125 27.1252.60 2.60% 2(278125) b) What is the angular velocity of the sphere at 2.00, minutes? (5) W= Angular Displacement Answer Units 0.02727 rad/s 2125) 1257 Time taken 60 2.60 Answer Units 6.54498 rad/s c) How much work was done to bring the sphere to the angular speed found in part b? (5) 2 I = 1/3 MR for hollow sphere 33 (3.1) (0.14) +0.04051 W = = = (0, 04051) (1257) 2 W= Answer Units 0.867659 J d) What was the torque needed to bring the sphere to the angular speed found in part b? (5) J=I9 = 0.04051 9-1257 60 J = 0.04051 (1258) Answer Units 0.265137 Nm