The linkage consists of two 6-kg rods AB and CD and a 20-kg bar BD. When 0=0°, rod AB is rotating with an angular velocity = 2 rad/s. If rod CD is subjected to a couple moment of M = 30 Nm, determine @AB at the instant 0 = 90°. (Ans: AB 3.49 rad/s.) B 1.5 m - 1 m 1 m M = 30 N-m