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If a magnet moves near a coil, it generates a changing flux which generates current due to Faraday's Law. Clearly there is no flux when we consider a straight wire, but it seems to me that a current should still form.

Each electron in the wire behaves like a small magnetic dipole (since they rotate around the nucleus). Then since magnets repel/attract each other, shouldn't a permanent magnet placed near a copper wire produce a current by repelling or attracting the electrons? It feels wrong because neither the magnet nor the wire are moving, but I can't see why there shouldn't be a current.

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  • $\begingroup$ Can you clarify if you asking about a moving magnet or a stationary magnet? $\endgroup$
    – M. Enns
    Commented Jan 6, 2020 at 20:28

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If a wire, coiled or not, is moving through a magnetic field, or the field moves near the wire, some current can be generated. Coils will have more wire in the magnetic flux and produce more current. If both the magnetic field and the wire are stationary to each other, no current will be produced.

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  • $\begingroup$ Can you tell me why the argument above is incorrect? Electrons behave like a dipole so can't it be attracted or repelled by a magnet? $\endgroup$ Commented Jan 6, 2020 at 22:01
  • $\begingroup$ The second paragraph here explains pretty well en.wikipedia.org/wiki/Electron $\endgroup$ Commented Jan 6, 2020 at 22:35

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