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Old November 4th 04, 01:30 AM
Roy Lewallen
 
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You have to use some care in applying the conservation of charge to a
system that includes radiation or other manifestations of displacement
current. Imagine a capacitor with widely spaced plates. Charge flows
into one plate of the capacitor, and an equal amount of charge flows out
of the other plate. You have to include both plates in the system when
counting up the total amount of charge that's conserved. Similarly, in
the case of a radiating coil, you have to count the charge that flows on
all nearby and distant conductors as a result of the (field created by)
the charge flowing on the inductor. That is, some of the charge that
flows into a radiating inductor flows out of other nearby and distant
conductors.

In the absence of radiation, all the charge that flows into an inductor
has to flow out, a point I and (much more eloquently) Ian and others
have tried to make, but which is lost on some of the most vocal
contributors to the newsgroup. This concept doesn't seem to fit neatly
into some of the preconceived theories, so is simply being ignored. In
the end, any theory that truly explains observed phenomena has to work
with physically vanishingly small inductors, for which the currents in
and out must be equal, as well as larger ones.

Roy Lewallen, W7EL

JGBOYLES wrote:
"If you look at HOW an inductor works, the current flowing in one
terminal ALWAYS equals the current flowing out the other terminal."



I think that is true. If you define current as electron flow, then the fields
and radiation that a large coil may be subjected to, will not increase or
decrease the number of electrons that the coil contains. As such, the amount
of electrons entering the base of the coil, will equal the same number exiting
the coil, with time displacement.
Consider a large physically long capcitor, with multiple plates. One can use
this as a loading element. There is no electron flow between plates. However
there is "displacement" current between the plates that has no physical
meaning. Now what? The capacitor will be just affected as a coil.
So, from the conservation of electron flow I don't know what to believe.

73 Gary N4AST