Me and a few friends started to argue about magnets. Of course we know there are the laws of thermodynamics that basically say you cannot generate energy from nothing.
But what of magnets? If i stick a magnet to the fridge it must be generating at least enough energy to not fall down due to gravity.
Where is this energy coming from? Should it not like run out of energy sometime?
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Laws of conservation, not thermodynamics.
They apply to magnets too. There’s no energy being exerted when a magnet sticks to a fridge. No useful work can be extracted from it without putting energy into the system. Sure, if you wanted to hold something onto the fridge and fight gravity, it would take energy, but a magnet is just sitting there.
Look at your chair. It’s on the ground. Holy shit, how can it do that, it just stays there! Because Earth has gravity. And that’s useful, but we can’t extract energy directly from the chair being in the floor. Same with magnets, even if they’re overcoming gravity.
It’s a force, not energy. Your chair has a downward force on it. But unless it moves, there’s no energy there. If it does fall, like on a teeter tauter or something, that IS potential energy. But then you have to lift up the chair again and put in energy to do it again. Same with magnetic force.
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