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enter image description hereI'm trying to determine in which direction a magnetic field will be produced in regards to the direction of current in an electromagnet. Will the end of the electromagnet from which current is drawn from always be the south pole? Or does it depend on the direction of coils (ie clockwise or anti-clockwise)?

Also, are the magnetic poles in either of the pictured electromagnets in the wrong position in respect to current flow and rotation of the coil?

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It depends on the sense of circulation of the current in the wire of the solenoid. If you take the solenoid in your right hand so that curved fingers copy direction of current in the wires, the thumb will show direction of magnetic field inside the solenoid. It thus points to the "north pole" of the electromagnet.

This picture may help to understand this rule: http://etc.usf.edu/clipart/35600/35671/rhrsole_35671.htm

Therefore, the direction of the magnetic field does not depend only on which end of the solenoid the current enters the solenoid, but also on whether the wire is a right-handed or left-handed helix.

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  • $\begingroup$ Thanks. I added a picture of two electromagnet representations I found on google images. Does this mean the one on the left is in fact incorrect? $\endgroup$ – Jake Davies Jul 7 '16 at 21:16
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    $\begingroup$ @JakeDavies Good eye: the coil on the left in your question has either the current or the field drawn the wrong way. The coil on the right in your question is correct. $\endgroup$ – rob Jul 8 '16 at 4:08
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Imagine that instead of a solenoid you have only one loop, apply Lenz law, that would give you the direction of the magnetic field lines generated by the electric current. Compare the field lines' pattern to the one which corresponds to the magnetic field lines of a natural magnet. Then change the direction of the current in the coil, and do the same analysis again.

What you should get at the end is that the poles' orientation of your electromagnet should depend on the direction of the current in the loops of a solenoid.

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Regarding your question about a pole position error in either of the pictured electromagnets. No they are both correct. If you visualize wrapping the fingers of your right hand around those electromagnets in the direction of current flow, you will find your thumb points to N pole in both cases. You do have to look carefully at the left hand pictured electromagnet to know that the current flows over the top and down the backside. Note that it shows the wire colored tan and the lines of force blue. Look to see which color blocks the other.

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