This is a question, I think, of "unknown unknowns." I know I don't understand something but I am not quite sure what I don't understand and I am trying to work through it.(adsbygoogle = window.adsbygoogle || []).push({});

So...

1)

I have been following some of the threads about current in wires and electrical fields and, if I understand it correctly, the electrical field in a current carrying wire is confined to the wire. Is that correct?

2)

If the above is correct and I consider a current carrying wire, then at any point outside the wire, the electric field is zero. Is that also correct?

3)

However, the magnetic field outside the wire is non-zero. Therefore I can consider a Poynting vector for this system. But the Poynting vector will, one again, be zero.

4)

Now, for a solenoid with constant current. Once again, the electric field will be confined to the wire wrapping. Is that correct?

5)

However, if the solenoid has a time-varying current, does that give rise to an electric field within the solenoid? I think Maxwell's equations to say it does. Am I correct?

6)

And what about outside the solenoid? Is there an electric field there for time varying currents?

Thanks for any help.

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# Electric Field of a Current

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