I'm wondering how one can squeeze more current through a given diameter
wire by means of increasing the voltage.
I'm wondering a bunch of other stuff too, but the answer to this question
seems basic to my eventual understanding of other questions.
"More current" means that more coulombs of charge pass by a given point
per unit of time. I take this to mean that more electrons flow past the
point.
If more electrons pass by the point per unit of time, does this mean that
the velocity of the electrons is greater at higher voltages, all other
things being equal? Is the means of getting more electrons through a
given wire to increase the velocity of the electrons by means of
increasing the voltage?
If so, then how fast do electrons travel?
I (think I) understand that the electrons do not necessarily pass through
the entire length of the wire, but instead, they travel between adjacent
copper atoms. When one atom near the source gets extra electrons, it
p***** some electrons to its neighboring atom. This propogates down the
wire from one end to the other, until eventually, the current reaches the
load at the other end.
And am I correct that at higher voltages, this process happens more
quickly? If one had a really long wire, could the time difference be
noticible and significant?
So how fast does this effect propogate down the length of the wire? And
is velocity of travel the mechanism that allows more electrons to "pass
through" a thin wire at higher voltage per unit of time?
OK, so that is my basic question, and I guess it assumes DC voltages. Is
that true?
Taking it one step further, ISTM that with AC, the electons starting at
the source might not get too far down the wire before polarity changes.
Here in North America, we switch polarity 60 times a second.
So are the same electrons going back and forth, back and forth, along the
same physical chunk of wire at AC voltages?
AND - what happens when we use low voltage and high frequency?
Specifically, what would happen if the switching frequency is
significantly quicker than the time required for the voltage change to
propogate all the way down the wire from the generator to the load? Does
the transmission system suffer weird phase problems?
And am I starting to figure out the term "Power Factor" using this line of
reasoning, or am I going in weird circles, and beginning my reasoning
process with defective premises?
OK. Lots more than one question. But I seem to have some basic
misunderstandings or ignorance that is not letting me figure this stuff
out in a manner I am confident of.
Any correction of basic misuderstandings will be greatly appreciated.
--
The whole problem with the world is that fools and fanatics are always so
certain of themselves, but wiser people so full of doubts.
-- Bertrand Russel
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