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Hello, Mike La Moreaux, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are some pages that you might find helpful:
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You are welcome – and welcome to Wikipedia. The problem was that each new paragraph started with one or more spaces. The wiki mark-up software treats that as an instruction to print the text literally, without formatting, which resulted in the text you saw. The solution was to remove the leading spaces. There is a little more about markup here. —BillC talk 20:39, 8 September 2009 (UTC)[reply]
Mike, I'll put the question another way. Consider your DC scenario in which the secondary coil unwinds without induction of any EMF. If the current suddenly became AC in that exact same arrangement, would we get an induced EMF? David Tombe (talk) 13:43, 30 September 2009 (UTC)[reply]
Mike, Sorry for not getting back to you earlier. And yes, I think that the discussion at Faraday's law has indeed run its course. I did learn alot from it, and I'm grateful to you for raising those issues. You introduced some very interesting case scenarios. I can see that our main clash lies in the fact that I see the energy transfer from the primary to the secondary, in the case of time varying induced EMF, as constituting EM radiation. You on the other hand don't. I don't of course see EM radiation as being involved in the motionally induced EMF as per v×B. (Maxwell actually eliminated v×B when he derived the EM wave equation in 1864)
It was a very interesting discussion, but I couldn't help sometimes thinking that you are perhaps too focused on trying to find flaws in Faraday's law. Sometimes the concept of 'conjuring tricks for physics audiences' flashed through my mind. I think that you may just about have a technical breach with the DC toroidal scenario, but I think that even that has been largely influenced by your belief that the (changing) magnetic field doesn't actually directly touch the secondary coil in the AC scenario. I think that it does.
I gave further thought to your idea of the ramp function generating a steady EMF. I still don't think that it could ever be possible in practice, because it would ultimately break down on the microscopic scale. But let's just say for the sake of argument that it is possible. In the AC scenario, we have a time varying induced EMF and hence no obstacle to the applicability of the EM wave equation. So is it not highly unlikely that EM theory is suddenly going to crash, just because we increase the current in the primary at a very particular 'ramp function' rate? David Tombe (talk) 03:57, 15 October 2009 (UTC)[reply]
You wrote: In view of the above conversation, I believe that I have come up with a proof that even the thin-wire version of Faraday's Law is false. Take a thin wire rectangular circuit and attach the pole of a permanent magnet to one side such that the lines of force are orthogonal to the plane of the circuit. Now move the circuit and magnet together rigidly in a direction perpendicular to both that side of the circuit and the lines of force. There will be a motional emf induced in that side of the circuit, but there will be no change in the flux linking the circuit. This violates Faraday's Law.
Really, the article talk page is not the place to be having this discussion, so I'll address what you said here. This gedanken-experiment is quite observant of you to notice and point out. The resolution comes from the fact that the magnet is moving, which, under relativistic electromagnetic theory, means that the B (magnetic) field it produces is partially transformed into an E (electric) field. This electric field is responsible for the emf. --Floorsheim (talk) 02:35, 27 April 2012 (UTC)[reply]
