18.115 A solid sphere of radius c = 30 mm is attached as shown to cord AB. The sphere is observed to precess at the constant rate o = 6 rad/s about the vertical axis AD. Knowing that B = 40, determine the angle 0 that the diameter BC forms with the vertical when the sphere (a) has no spin, (b) spins about its diameter BC at the rate of = 50 rad/s, (c) spins about BC at the rate of = -50 rad/s. B D 2c Fig. P18.115 and P18.116