Re: Error in Wikipedia article: Faraday's law of induction

On Jul 12, 12:22 pm, phil-news-nos...@xxxxxxxx wrote:

I'll say this much. I'm also very much interested in this subject and
would like to try to find a way to combine Lorentz and Faraday laws
into one thing. I DO believe that as you put a current down a wire the
magnetic field expands aways from a wire causing an apparent Lorentz
force at a distance. After all, we know that as we put current down a
wire energy is stored in the magnetic field. Causality means that
energy is traveling away from the wire at the speed of light or
slower. Therefore, the "expanding field" theory could make sense. But
I've never found a calculation that would work to prove this. You try
and nothing ends up making sense.

Also as for Faraday Disks including the One Piece Faraday Homopolar
Device (OPFHD) which means magnets rotate with disk. You CAN split the
disk into radials or as Tesla proposed into a spiral which actually
enhances the magnetic field as it produces current. It works the same.
Yes then in the case of non-rotating magnets one actually can then say
that the wires DO "cut" the flux. But in the one piece case, the
problem is that you are using a loop to measure emf. One scenario is
this: The magnet and the disk turn together. Therefore, there is NO
emf induced into the disk no matter WHAT it's configuration! There is
NO relative motion between them. The emf you are measuring is coming
ALL from the wire loops hooked between the disk and meter. A similar
argument ensues if you assume the magnetic field does not rotate with
the magnet.

These kind of experiments are easy to do. I've done quite a few. Just
find some old dead large loudspeakers and remove the large ceramic
disk magnets from them (they are usually glued in so it can take some
work). Then set up your ideas. The voltages and currents from a
Faraday disk should easily light most LEDs. But dig. They DON'T! All
your various ideas somehow almost always seem to forget about the
"complete" loop thing. The laws of line integrals in a conservative
magnetic field are totally unforgiving! Nope, the LEDs do NOT light!
Just gets you scratching your head. Evenually I had to join everyone
else in the idea that the measurement cannot be made with a loop. It
has to be made electrostatically. I don't like it, but it's just how
it is.



.

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