I'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?
Best Answer
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.