Hello All, I just read in a book that springs are pretty much analogous to capacitors in terms of energy considerations to capacitors. For eg. If a mass m suspended by a spring comes to rest after downward displacement y, Assuming compression = y for equilibrium, mg=ky thus k = mg/y loss in G.P.E for the block =mgy gain in elastic P.E of spring = 1/2(ky^2) = 1/2(mgy) ----->Half energy is wasted can't this be compared to charging of capacitor by a battery? energy lost by battery = qV but energy gained by capacitor =1/2(qV) ------> Half energy is wasted I have difficulty in solving capacitor probs. Does this mean that springs can be used instead of them?