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Re: TC Electrostatics

>12/5/96
>
>You wrote: 
>
>snip
>[megaship]    The force of interaction in the wires is not a Coulombic 
>force since neither wire has a net charge; it's totally an 
>electromagnetic force.
>
>RWW
>
>I would greatly appreciate an explanation of the two types of force to
<which you refer and a concise description of the difference between 
>them if this would not be an imposition.  Wallace Edward Brand
>
>
12/8/96

Sure, I'll give it a shot.  Somehow thought, I believe a man with your 
knowledge and experience is only trying to stimulate excellent 
discussion.  This is good.

Richard Hull has mentioned that measurement of charge on an electron 
measures only an 'effective charge'.  This is true.

Cavendish's original torsion beam experiments measured electrostatic 
charge.  Coulomb subsequently applied his equation, F = k[qq']/r^2, to 
Cavendish's experimental work.  F is a static force related to Newtons 
in S.I. nomenclature.

Current flowing in adjacent parallel wires produces force interaction 
between the wires (remember the left hand rule?).   By carefully 
controlling current flow this force between the wires can be 
experimentally measured in Newtons.  This is a force produced 
electrodynamically by EM current, not electrostatically.  

Next comes a giant leap in logic (perhaps faulty logic).  An 
'effective' Coulombic charge is assigned to an electron by equating 
these electrodynamically produced forces in Newtons to 
electrostatically produced forces, also in Newtons.  A major error is 
in assuming electrons "flow" in a conductor at near relativistic 
velocities.  I doubt seriously the true number of electrons actually 
flowing in a conductor at constant current can be determined with any 
great accuracy.  It's probably many, many orders of magnitude off that 
used to calculate the official charge of an electron.  Now we talk of 
'effective' electron flow rather than true electron flow in a 
conductor.  It's easy to see where all this is leading.    

Hull is correct in his conclusion that the energy of electrostatic 
charges may do much more work than that of electrodynamically 
determined charges assigned to electrons.

The theoretical discussion of electrostatic vs EM electricity is beyond 
the scope of his thread.  Steinmetz has an excellent, easy to read 
description in his "Electric Discharges, Waves and Impulses".

RWW