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Hyperphysics Picture Wrong?

  1. Apr 12, 2010 #1

    Is it me, or is the polarity on the voltmeter wrong for this mutual induction example.


    In particular the 2nd and 3rd images of the first page Coupled Inductors.

    I agree with the change in B field and induced current direction, but the current that is drawn in the 2nd image should be consistent with a negative EMF in the voltmeter since current travels from + to -.

    Same reasoning in the 3rd image down.


  2. jcsd
  3. Apr 12, 2010 #2
    I think they are indicating the voltage drop across the resistor, which always goes + to - in the direction of current.
  4. Apr 12, 2010 #3

    For some dumb reason, I didn't see the resistor and was treating the voltmeter as the source.

    The inductor coil should be the effective source, and the current flows out of the positive terminal through the load, to the negative terminal.

    Thanks again

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