Demagnetization of a permanent magnet and lenz's law

[abdo799]

this video ( ) demonstrates lenz's law, if the current produced by the magnet fall induces an opposing magnetic field , after many tries , can this field demagnetize the magnet , another thing, consider this : if the copper pipe was instead a pvc pipe, and i wrapped around it copper wires , so when the magnet falls a current flows in that wire , after the magnet reaches it's terminal velocity , the magnetic field will have an opposing field , will they cancel each other? In other words , will current stop flowing in the wire after the magnet reaches it's terminal velocity?

 

[Vailanor]

No, the opposing magnetic field cannot demagnetize the magnet, as the strength of the induced current will not be strong enough to do this. However, if the copper pipe was replaced with a PVC pipe and copper wires were wrapped around it, when the magnet falls a current would flow in the wire, and this current would continue to flow until the magnet reached its terminal velocity. The opposing magnetic field would not cancel each other out, instead they would interact with each other and cause the current to weaken before eventually stopping.