Lenz's law with neodymium magnet + aluminum ingot is revealed. This explains the "UNKNOWN MYSTERY" videos that people have done with hard drive platters and magnets.
Currents bound inside the atoms of strong magnets can create counter-rotating currents in a copper or aluminum pipe. This is done by dropping the magnet through the pipe. When done, the descent of the magnet is observably slower than when dropped outside the pipe.
When an emf is generated by a change in magnetic flux according t
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