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In a generator a magnet spins in the middle of a coil of wire and the changing magnetic field causes current to flow, but the current changes direction whenever fields from a new pole of the magnet cross a point on the wire, so will the current move towards the north pole or towards the south pole (rather the part of the wire being touched by the pole's magnetic field).

I know that when you use current to magnetize something the north end of the magnet is the end that was negative, so I would assume that current would move away from the north. Is that correct?

To make things more clear I have added this diagram. Assume the generator is running. Would electrons be taking the blue or the red path? enter image description here

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(a) "when you use current to magnetize something the north end of the magnet is the end that was negative" I'm afraid that this suggests a misunderstanding. The direction of magnetisation is determined by the direction of current around the coil, not along its length. You need to consult a textbook and learn about the right hand grip rule.

(b) If, in your diagram, the left hand side of the coil is coming towards us, and the right hand side is going into the screen, away from us, then, according to Fleming's right hand generator rule, the blue arrow gives the direction of the induced conventional current (if the circuit is complete). Therefore the electrons, being negative, are flowing in the direction of the red arrow. Things are reversed if the right hand side of the coil is coming towards us.

It is misleading to think of electrons going towards or away from either of the magnet's poles.

(c) Electromagnetism needs to be learnt step-by-step. It isn't difficult, but there is quite a lot of detail to master. It's much easier to do this of you follow a logical sequence – such as you will find in a competent textbook.

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The image you presented looks like a DC motor. If thats the case, there would be a DC source connected at the terminals. When current flows through the wire, a temporary magnetic field is formed due to the current flow through the wire. This temporary field repels the magnetic field felt from the magnets and causes the wire to flip over.

What causes the wire to keep flipping is called a commutator (https://en.wikipedia.org/wiki/Commutator_(electric)). This reverses the current flow after the wire has flipped. The reversing of the current at timed intervals causes the wire to keep flipping. If there was no commutator to reverse the current the wire would only flip once where it would now be in the most stable state of the magnetic field. It's the reversing of the current that keeps the motor moving.

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  • $\begingroup$ This does not answer the question. The OP asked whether the electrons flowed down the red or blue wire. $\endgroup$
    – LincolnMan
    Mar 22 '20 at 18:29

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