Just started vibrations and having trouble applying energy conservation as a means of finding the natural frequency. So I know wn=root(k/m) and I know that Tmax=Vmax the problem is: In the complete assembly, the top of the float is connected to one end of a uniform bar (mass m and length l) which is freely pivoted at its midpoint, as shown below. Derive an expression for the natural frequency of the complete indicator system. Hint: use Tmax=Vmax answer: root(6g/(L(3+m/M))) I do not really have a clue as how to get the energies. Thinking that the maximum potential energy Vmax is 1/2*k(x0^2) where x0 is maximum displacement of the cylinder in the water. Then Tmax is supposed to be 1/2*m(x0*wn)^2 where wn is natural frequency. Something like that. I am missing an I somewhere though as there clearly is rotation in the problem. Any help?