A 10-lb collar C is released from rest in the position shown and slides without friction on a vertical rod until it hits a spring of constant k = 50 lb/ft which it compresses. The velocity of the collar is reduced to zero, and the collar reverses the direction of its motion and returns to its initial position. The cycle is then repeated. Determine

(a) The period of the motion of the collar,

(b) The velocity of the collar 0.4 s after it was released. (Note: This is a periodic motion, but not simple harmonic motion.)

1.5 ft