Don Lancaster wrote:
Floyd L. Davidson wrote:
Don Lancaster wrote:

DC, of course, cannot exist at all ever. Because it would have
to be unvarying through infinite time.


Boy, you are *pedantic*!

Can't we just define DC as current that doesn't vary "much"
for at last a "long" time. Granted that is ambiguous, but
what else would we the argue about, weather?


No.

Sum a 1 volt peak sinewave with a 0.6 volt dc term and you have a
waveform whose polarity continuously changes but whose average value
is continuous.

Looking at the Fourier terms makes this waveform perfectly clear.
Calling it "AC" or "DC" does not.

"AC" or "DC" are gross and meaningless oversimplifications.

That's going a bit far. "Meaningless" means no meaning, and that is not
really an accurate description for the terms AC and DC. They have a
pretty well understood meaning, despite some suggestions in this thread.

"quotes with no meaning, are meaningless" - Kevin Aylward


Kevin Aylward

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