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Re: "Faraday's Final Riddle"



But isn't it true that magnetic fields are quantized and that
superconductors are 'sensitive' to single quantum changes??? Does
this not justify some sort of 'reification'

(I've got my Nomex undies on!!!!!!)


At 1:07 AM -0400 10/4/99, Bob Sciamanda wrote:
I don't like to be a "flamer" but this paper propagates the pernicious
idea (common in engineering circles) that Faraday induction results from
the "cutting of magnetic field lines" by a conductor. (another bastard
offspring of the reification of static fields).

The correct, basic physics is that Faraday induced emfs result from:

1) the Q*VxB force of a magnetic field on a moving charge (called "the
generator principle" when Q is a conduction electron in a moving wire),
and/or

2) the electric field which is sourced by a time changing magnetic field,
as described by Curl E = -dB/dt.

1) requires that (in the observer's frame) a conductor is moving where
there exists a magnetic field;
2) requires that (in the observer's frame) the magnetic field vector is
changing in time at some fixed space positions.
"Cutting B lines" has nothing to do with anything and leads only to
confusion.

Bob

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