A mechanical device shown in Figure Q3(b) is in vertical plane which consists of two balls of mass 3 kg each, a central collar of mass 4 kg and a spring of stiffness k = 650 N/m which is uncompressed when = 0 from which the mechanism is released from rest. Ignoring the mass of all the links and friction in all the hinges at the joints, determine (i) the velocities of the balls and the collar when = 60. If a spring of the same undeformed length but with higher stiffness is used, evaluate its effect on the speed of the collar and justify the answer using the dynamic fundamental. 3 kg 4 kg Figure Q3(b) 200 mm 200 mm 3 kg - 300 mm