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I have a question about an ideal inductor. I understand the induced EMF due to moving charge and the more turns of an idealized inductor the higher the non-conservative induced emf is opposing current. I am having a hard time with energy conservation though. The induced EMF opposes current flow for some amount of time, therefore the voltage source (battery) gets polarized and has to do work to move charges aganist the electric field resulting in a loss of potential energy (negative work). Therefore in this aspect there would be an energy loss in the inductor correct?

Furthermore, is this energy recovered due to the inverse of the magnetic flux when it starts to drop and the inductor generates an induced emf (PE) to push the charges in the direction of the current drop?

In addition, if the inductor is not ideal and has some winding resistance than some energy would be loss internal as joule heating correct?

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Therefore in this aspect there would be an energy loss in the inductor correct?

There is no energy loss in the form of resistance heating in an ideal inductor since it theoretically has no resistance. The work done by the voltage source in delivering current to the inductor is stored in the inductors magnetic field and is given by

$$E_{L}=\frac{LI^2}{2}$$

Where $I$ is the instantaneous magnitude of the current in the inductor.

Furthermore, is this energy recovered due to the inverse of the magnetic flux when it starts to drop and the inductor generates an induced emf (PE) to push the charges in the direction of the current drop?

The current in the ideal inductor is proportional to the magnetic flux. When the flux starts to drop the current starts to drop and the energy stored in the magnetic field starts to drop. This energy is transferred from the inductor back to the voltage source where it originated. Again, all this assumes zero resistance in the entire circuit. It also assumes energy lost due to electromagnetic radiation is negligible.

In addition, if the inductor is not ideal and has some winding resistance than some energy would be loss internal as joule heating correct?

That is correct.

Hope this helps.

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  • $\begingroup$ Not directly related to the OP: what if the ideal inductor is a part of a speaker, generating sound? In this case we shoudl have energy losses, even though the inductor is ideal. $\endgroup$
    – Roger V.
    Commented Feb 24, 2021 at 8:53

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