Let me blow everyone's mind by pointing out that in even elementary
circuit analysis, the intention sometimes is to solve for currents which
do not even physically exist in the actual circuit: loop currents, for
example. They bear some relationship, sometimes, to actual branch
currents, but not always and not at all necessarily.
So it really is sort of a waste of intellectual effeort to insist that
every "current" in a circuit must have a direction and associated
polarities that happen to coincide with the physics of how charge
conductors happen to move through certain devices.
Again, current is a mathematical construct of use in circuit analysis
and need not bear any resemblance to the actual motion or direction of
charge carriers in a circuit. In fact, most modern circuit analysis is
done through matrix methods and it is frequently difficult to identify
which terms in the matrix eve correspond to "current."
I did not intend to start a war among "engineers" and "techicians" with
this and the prior discussion. Some folks have had a mathematical
background for this stuff and others haven't. Some of those who have and
most of those who have not often seek a physical, see it on the circuit
diagram, kind of understanding. Nothing wrong with either approach.
But there is equally nothing "wrong" with systematic circuit analysis
conducted according to established laws and procedures that employ
"conventional current." And, if any of the pre-assigned current
directions turn out wrong in the final analysis, they will have a neat
minus sign before them to remind us of that fact.
The bottom line: whichever way one goes about it, if the right answers
are obtained, then the method has been applied correctly. The only
problem is that some ad hoc methods only work in special cases. The more
formal methods tend to yield consistent and correct results in all
cases.
Interesting stuff . . .
72/73, George W5YR - the Yellow Rose of Texas NETXQRP 6
Fairview, TX 30 mi NE Dallas in Collin county QRP-L 1373
Amateur Radio W5YR, in the 55th year and it just keeps getting better!
Icom IC-756 PRO #02121 (9/00) Kachina #91900556 (12/99) IC-765 (6/90)
Dan wrote:
>
> Sort of like if you imagine a canal, and there's a obstruction in the canal.
> When the obstruction moves forward the "water" or in this case "nothing" is
> now
> where the obstruction "electron" was. In the circuit I wouldn't say that the
> holes themselves move though, to me it sounds like more of an accumulation of
> holes. It seems to me that thinking of holes at all is really pointless.
> There
> doesn't seem to me to be any logical point in thinking about where an electron
> was or what it leaves behind. It's enough to say that it goes from point a to
> point b through a load of some sort(tentec rig) and "gets stuff done" in that
> process. When you think of a water current that is a physical moving
> material,,
> , nothing can't move because it has no method of moving itself along. If it
> is
> displaced or repositioned into a different spot"throwing a ball into water
> say.." then that is understandable, but it is not a "current" as the
> definition
> in a dictionary will define. It's more of a displacement sounds like to me.
> Everyone's brain hurting yet?
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