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Re: non-potential voltage



At 01:49 PM 4/19/00 -0400, Bob Sciamanda wrote:

Consider a steady state DC circuit with one particular (compound) branch
consisting of a resistor in parallel with a capacitor.
With or without fringing, K's laws apply - and usefully.

OK, evidently Bob wants to perform a strictly-DC analysis of capacitors.

I fail to see how such an analysis is useful, with or without reference to
Kirchhoff's laws. The elementary, widely-used, and well-founded
engineering rule is to completely disregard capacitors when doing the DC
analysis.

=================================================

What is the point here? Does anybody seriously disagree with the the
following assertions???
1) Kirchhoff's laws, as usually formulated, apply to loops of discrete
"circuit elements" and to the "nodes" between circuit elements, the
existence of which is only an approximation.
2) K's laws are tantamount to the approximations
2a) there are no significant currents carried by changing electric
fields (displacement currents), except inside certain circuit elements.
2b) there are no significant voltages induced by changing magnetic
fields, except inside certain circuit elements.

(The simplest circuit elements exploiting displacement currents are called
"capacitors" and the simplest circuit elements exploiting induced voltages
are called "inductors" and "transformers".)