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Emf in a wire?

  1. Feb 26, 2009 #1
    Hey everyone,
    I was tinkering with a battery, wire and such earlier, and I discovered something odd. :bugeye:

    I had a steel? wire and I placed the ends onto the terminals of a D battery for a time, and obviously, it warmed up. But I also had a thing that played a recorded music track when two AA batteries were inserted; I only had one AA installed. I then placed the ends of the same steel wire onto the contacts of the player where the missing AA was to be.
    The music continued to play! with only one battery and the wire that was previously in contact with the D battery.

    Anyone have an idea why its doing that?
    To provide energy for the player, the wire obviously needs to provide a voltage, and therefore current, of its own.
    How did it acquire that from the D battery?

    EDIT: Apparently, I observed the same thing from a wire that was never previously in contact with any energy source i.e. a battery.
    Something to do with magnetic fields? =O
    Last edited: Feb 26, 2009
  2. jcsd
  3. Feb 26, 2009 #2
    I'm thinking that you probably just completed the circuit, the wire acted as a short.
  4. Feb 26, 2009 #3
    Yeah I guess that's a better explanation for it, there was a reduced sound quality as well.

  5. Mar 1, 2009 #4
    Try it with a wire that you didn't previously short a battery with. You'll find that the music will play. It doesn't need that exact voltage. There's no way to turn a length of wire into a voltage source. You could induce a charge, but that's not the same as making it have a voltage gain across the wire.

    Keep tinkering! That's the way to do it!
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