Is the Polarity on the Voltmeter Wrong for this Mutual Induction Example?

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The discussion centers on the polarity of the voltmeter in a mutual induction example. The original poster questions whether the voltmeter's readings are correct based on the direction of current flow and induced EMF. A participant clarifies that the voltmeter indicates the voltage drop across a resistor, which aligns with conventional current flow from positive to negative. The original poster realizes they misinterpreted the voltmeter as the source instead of recognizing the inductor coil as the effective source. The clarification helps resolve the confusion regarding the current direction and voltmeter readings.
azaharak
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Hi

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

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/indmut.html

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.

Thanks

Az
 
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I think they are indicating the voltage drop across the resistor, which always goes + to - in the direction of current.
 
Thanks..


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

Az
 
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