- #1
Sparky_
- 227
- 5
Greetings,
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
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