Something Vexing me about Magnetism and Conservation of Energy I have been thinking about an issue at work and it has been bugging me so I thought I would post something on here to see if anyone can explain where my thought process is going wrong. Say you have a super conducting magnet. It is a big one. The current is switched on and so the magnet becomes active. As it is super conductive the current is not impeded and continues to flow. The magnet is used to lift a large weight off the ground. At somepoint the current is channeled off somewhere else, the magnet stops working and the weight falls. The energy of the weight falling under gravity is captured somehow. The current is channelled back to the magnet, weight is lifted again and so on.... So, my question is, does this system not break the conservation of energy principle? Are we not getting something for nothing here? I am sure I am missing something in my understanding of magnetism, but I thought it was just a field and so no actual mass is lost when it is active?