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What really causes electromagnetic induction/ the motor effect?

  1. Mar 17, 2012 #1
    When a conducting wire is subjected to a changing magnetic field, what causes the electrons in this wire to move?
    Conversely, why does the movement of current in the wire (with a non-'moving' magnetic field) cause the wire to move?
    I understand these phenomena macroscopically (and that they are different sides of the same electromagnetic coin), but at the most fundamental level, what happens?
  2. jcsd
  3. Mar 18, 2012 #2
    I believe the idea is a called a "Hole Charge."

    I don't know exact chemistry of conductors, but basically, they are usually fairly stable.

    Electricity is more of a pulling effect.

    When you pull one of the electrons from one end of the wire, those atoms pull electrons from neighboring atoms and the "effort" travels up the wire. The "effort" is near the speed of light. The electrons themselves do not travel at the speed of light. In fact, the more they have to travel, the more heat it causes and resistance builds up.

    Thus A/C is more efficient then D/C.

    The more stable the metal, the better conductor is it makes. For example: Gold is one of the best conductors and does not oxidize like many others. At least, I think so.
  4. Mar 18, 2012 #3
    Fundamentally, a charge experiences the Lorentz force, period. The E and B fields at the charge determine that force.

    Note that a changing magnetic field creates an electric field. That's one of the fields that exerts a force on the charge in the case of a time-changing magnetic field.

    Every one of Lord Challen's observations is incorrect.
    Last edited: Mar 18, 2012
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