Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Wire does a loop of wire create a norh pole and a south pole

  1. Jul 21, 2008 #1
    Hello everyone,

    I just read that in a loop of wire if the current is anticlockwise that part is a north pole. I'm just wandering what do they mean by this. I thought only magnets have north poles. Any help would be appreciated. Thanks :smile:
  2. jcsd
  3. Jul 21, 2008 #2
    Sounds like it's talking about an electromagnet, where a coil of current carrying wire creates a magnetic field the same as that of a bar magnet, with a north and south pole. Looking end on to the electromagnet, the north pole will have an anticlockwise current and the south pole will have a clockwise current.
  4. Jul 21, 2008 #3
    A loop of wire with current and a magnet are very similar from the point of view of their behaviour in an electric field.

    It may help to thinkg of "poles" as just an abstraction and not something as "solidly real" as having shape and extension. In fact, the north and south poles are not localized entitities, but rather just "directions". A magnet has an "up" and a "down", and so does a loopwire with current: "up" or "north" is the side of the wire you're looking at when you see the current going counterclockwise. A magnet also has a current flowing on its side surface, so when you look at it from the "north" side you see the side surface current flowing counterclockwise as well.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook