When a 20 N can is hung from the bottom of a vertical spring, it causes the spring to stretch 20 cm.
(a) What is the spring constant?
(b) This spring is now placed horizontally on a frictionless table. One end of it is held fixed, and the other end is attached to a 5.0N can. The can is then moved (stretching the spring) and released from rest. What is the period of the resulting oscillation?