[Physics] How is the direction of a compass affected by a current in a wire

electromagnetism

If I place a compass over a wire(such that the wire is positioned north-south) with charge flowing through it, and it points northeast, how can I determine the direction of the electron current flowing through the wire?

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Here you can see the magnetic field. This answer your question right?

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[Physics] Figuring out North and South Magnetic Poles for Earth

You are correct in saying that the pole near the Arctic circle is really the south pole of the Earth's magnetic field because the north pole of a bar-magnet points towards it. (Wiki)

That said, it is purely convention what you define on a bar magnet to be north and south - we've named the side that points towards the Arctic circle to be the north pole of the bar magnet, and since people don't immediately identify this seeking behavior as opposite poles attracting, we tend to think the earth's field at the Arctic circle is also a north pole when it is strictly speaking, a south magnetic pole.

Also, I would add that the magnetic poles don't coincide with the geographic poles - the latter define the points of intersection of the Earth's rotational axis with the surface of the Earth. We know for a fact that the magnetic poles have shifted (even reversed) with respect to the geographic poles during the history of the Earth. (Wiki)

[Physics] How to relate the direction of a compass needle to the direction of a current

The right hand rule is a trick for remembering the direction of a magnetic field generated by a current in a wire. The compass is showing you what direction the magnetic field is in, so you can use the right hand rule to work out whether the current is flowing north to south or south to north.

There's a good diagram of the magnetic field around a wire here. This should help you work out why the compass might point ina different direction above and below the wire.

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[Physics] Figuring out North and South Magnetic Poles for Earth

[Physics] How to relate the direction of a compass needle to the direction of a current

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