The light rod is pivoted at O and carries the 5- and 10-lb particles. If the rod is released from rest at ? = 60° and swings in the vertical plane, calculate
(a) the velocity v of the 5-lb particle just before it hits the spring in the dashed position and
(b) the maximum compression x of the spring. Assume that x is small so that the position of the rod when the spring is compressed is essentially horizontal.