$\textbf{1)}$When I consider a dynamical system what tells me that there is a dissipation of energy?
For instance if I have a RLC circuit and I consider with $E$ the total energy absorbed in a period $[0,t]$ by the network, in order to have dissipation of energy this $E$ should be greater than the variation of energy stored over this period?
$\textbf{2)}$My second question is: can I consider the total power $VI$ that flows into the network such that its integral gives me the total energy $E$?
Thanks in advance.