6-lb collar C is attached to a spring and can slide on rod AB, which in turn can rotate in a horizontal plane. The mass moment of inertia of rod AB with respect to end A is 0.35 lb . ft . s 2 . The spring has a constant k = 15 lb/in. and an undeformed length of 10 in. At the instant shown the velocity of the collar relative to the rod is zero and the assembly is rotating with an angular velocity of 12 rad/s. Neglecting the effect of friction, determine
(a) the angular velocity of the assembly as the collar passes through a point located 7.5 in. from end A of the rod,
(b) the corresponding velocity of the collar relative to the rod.
