The spring attached to the 0.6 kg sliding collar has a stiffness of 200 n/m and an unstretched length of 150 mm. The speed of the collar in position A is 4 m/s to the right. Using the work-energy method or the conservation of energy method, calculate the following: a) the velocity of the collar as it passes position B. b) the normal force of the curved rod on the collar when it passes position B. -400 mm A 0.6 kg k=200 N/m 100 mm 200 mm JB