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Question on electromagnetic repulsion

  1. Mar 12, 2009 #1
    I have made a simple electromagnet with an iron nail, insulated copper wiring, and a 9v battery. My intention is to use the electromagnet to repel a small permanent magnet, but for some reason, I can only get the electromagnet to attract the permanent magnet. I figure I must have a problem with connecting the poles (S to S or N to N.)

    I'm thinking maybe this is happening because the force of the permanent magnet being attracted to the nail is greater than the force of the magnetic repulsion.

    Any suggestions? What can I do to get repulsion?

  2. jcsd
  3. Mar 12, 2009 #2
    An object cannot be attracted, but yet be repealed at the same time. You should have at least posted some dimensions of the magnet (length, width, mass, etc.) and the type of battery that you are using and the current that it delivers.
  4. Mar 13, 2009 #3
    Because of the resistance of copper wires, you are much better off getting a 1.5 D cell for your power source. 24 Ga copper wire is about 38 ft per ohm, so you should use about 100 ft for your coil.
  5. Mar 14, 2009 #4
    The permanent magnet is circular, about 1-inch diameter and about 1/4 inch thick. It's not very powerful.

    The nail is 6 inches long. I have no idea how many feet of wire I used or how many coils, but the entire thing is covered.

    Hopefully I have a 1.5 D cell laying around somewhere that I can try out.

    Thanks for everyone's help.
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