Electric fields in an Inductor

AI Thread Summary
In an inductor with negligible resistance, the total electric field within the coils is considered to be zero, despite the presence of individual non-conservative (En) and conservative (Ec) electric fields. This assumption simplifies the analysis and derivation of equations related to inductors, but raises questions about its validity. The discussion highlights that while superconductors exhibit zero resistance, they still rely on magnetic effects for electric fields. Type I superconductors have zero resistance but are limited in magnetic field strength, while Type II superconductors typically have some resistance. The conversation emphasizes the need for clarity on the experimental basis of these concepts in the context of inductors.
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Let's assume we are dealing with an inductor whose coils have negligible resistance. Then a negligibly small electric field is required to make charge move through the coils, so the total electric field Ec+En within the coils must be zero, even though neither of the field is individually zero.

En and Ec are the non-conservative and conservative electric field respectively.

I've quoted this from the textbook I'm using (University Physics by Young and Freedman 12th edition).

Now, it seems to me that the author just invoked the assumption that the inductor have negligible resistance and hence it only needs very small electric field (thus approximately zero?) to move the charges through it out of nowhere.

It seems wishy-washy to me, it's very convenient so that we can just advance through the discussion and go ahead with the derivation and come up with a very nice equation. My question is, really, how come the net electric field within an inductor is zero? The proposition that 'the inductor just have a very very small resistance so the electric field is zero' isn't very convincing to me, can anyone expound on this for me?
 
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Use superconductors if "very small resistance" is not small enough for you. They have zero resistance, and all electric fields have to come from magnetic effects.
 
@mfb: Does that mean that I just have to believe that proposition? I mean, if it's an experimental fact, then I don't have any problems with it. I'm just a little irked by how it's presented to me I guess, or most probably I've missed something crucial.
 
It is an experimental fact that you can have setups where resistance is negligible (or even zero).
You can have other setups as well, but they are not discussed in your quote.
 
Only type I superconductors have zero resistance, but are limited to a few mT. Type II superconductors, which are normally used for coils, have a resistance.
 
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