Problem 4 In the mechanism shown, each of the two wheels has a mass of 30 kg and a centroidal radius of gyration of 100 mm. Each link OB has a mass of 10 kg and may be treated as a slender bar. The 7-kg collar at B slides on the fixed vertical shaft with negligible friction. The spring has a stiffness k = 30 kN/m and is contacted by the bottom of the collar when the links reach the horizontal position. If the collar is released from rest at the position 0-45° and if friction is sufficient to prevent the wheels from slipping, 150 mm 375 mm 375 mm determine (a) the velocity vs of the collar as it first strikes the spring and (b) the maximum deformation x of the spring. 150 mm