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Re: Displacement Current Referances



Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "SF by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<sfusare-at-adelphia-dot-net>
> 
>     Here are a few referances that some may find interesting per the
> debate on the displacement current
> and the presence or absence of an associated B field:
> 
> D. F. Bartlett (Professor - University of Colorado Boulder), "Conduction
> current and the magnetic field in a circular capacitor"
> American Journal of Physics #58 (12), p 1168 - 1172 (1990) (Squid
> detects no B field to accompany displacement current
> in a slowly discharging capacitor. B field that is detected is fast case
> can also be described using the conduction current flowing
> in the plates)

I looked at this paper today, and also at some of its references.
They appear to be correct (and AJP is a serious peer-reviewed journal). 
In the described cases, all the magnetic field can be explained by 
currents in the wires and capacitor plates.
(As I was already suspecting...).
 
> Granted that an academic title does not automatically confer competence.
> Also granted that both Dr. Jefimenko
> and Dr. Bohren completely avoid mention of the unpleasant side effects
> of the theory they posit (so how does
> a TEM wave propagate?). But the works (Jefimenko's in particular) are
> very well done and bear reading by
> those on both sides of this debate.

I think that the trick is that these analyses assume "quasi-static"
conditions, where there is no irradiation, the potentials at all
conductors are uniform, and everything happens instantaneously.
When these conditions are not met, the "displacement current" 
appears, with its associated magnetic field. The conditions that 
make this happen are quite difficult to reproduce experimentally
in a way that allows easy measurements, and also difficult to analyze 
precisely. 
I am thinking about an experiment to show what really happens.

Look here (and look at the comment at the end):
http://www.physics.umd.edu/deptinfo/facilities/lecdem/k2-63.htm

Antonio Carlos M. de Queiroz