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In Feynman's lectures - vol. 2 either chap 19, 21 or 23 - I think 23 (I'm at work and don't have the lectures here), Feynman shows in a capacitor that a changing E-Field induces a B-field, then he shows that the B-field induces a new E-Field (he calculates the E-field) and then adds the 2 E-fields together. Well he says that "new" E-field creates a new B-field - he calculates that new B and adds the two B's together and so on.

He does 3 or so to see the pattern.

He ends up showing the E-field and B-field is this complicated expression involving a Bessel function.

I had under-grad electromagnetics - junior and senior level and this was never mentioned.

This Feynman lecture and results does not seem obvious to me -

I recall solving for the "E" field or the "B" field in class and it would be 1 step integration of derivation - box the answer and your finished.

Can you elaborate further on this?

Why was it not mentioned in electrodynamics (under-grad level at least)?

It seems so interestesting but I never would have known to go there, I would have stopped at the first calculation.

I find this lecture very interesting but do not feel comfortable with it (yet).

Can you all discuss it a little to help make it more obvious or clearer?

What other physical phenomina behave this way that are overlooked because we stop at the first step?

Thanks

-Sparky

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# Discussion on Feynman lecture - E / B Field

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