1. The problem statement, all variables and given/known data A light rod of length 0.5 m has two point masses of mass 1.6 kg attached at either end. The rod is pivoted about its centre and is attached to a spring which exerts a moment on the rod that is proportional to the angle the rod is displaced from the equilibrium position and which attempts to return the rod to the equilibrium position. The rod is displaced 0.27 rad from the equilibrium position and released from rest. If the spring constant is 5.4 Nm.rad-1 what is the period of the resulting motion? 2. Relevant equations y = Asin(ωt) = Asin(√((k/m)t)) 3. The attempt at a solution I'm not sure if that's even the correct equation that I would use in this situation. All the variables are there, so it must be so... How would I derive period t from that?