Blame it on Eddy

“Eddies,” said Ford, “in the space-time continuum.”
“Ah,” nodded Arthur, “is he. Is he.”

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Everyday Electromagnetism

This time, though, Eddies in the penny. And he enforces Lenz’s law.

You can see a similar effect if you drop a magnet down a copper pipe, because the eddy currents will flow, and the induced field is such that it opposes the acceleration, so you get braking.

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If you want to be more practical, instead of moving the magnet you could move the copper around, cyclically, and tap into the current that would flow. Just a thought.