Steve Nosko wrote:
. . .
I was, however, a bit puzzeled, Roy, why you went to the trouble of
calculating the the RMS value of a power earlier. I suspect it was just to
show that the value is indeed different (didn't check your math).
Yes, that was the only reason. As I mentioned, I'd never before had the
occasion to calculate the RMS value of a power waveform -- it's simply
not useful for anything. Except to illustrate that it's different from
the very useful value of average power.
I will differ with Roy on one issue. The RMS value of voltage and current
have, for many years, also been referred to as the "effective" values. This
was to relate it to the DC heating effect (of resistance) we are all
familiar with. It is, indeed just as "effective" as the same DC value, in
producing power. This is another terminology issue I suspect some of you
may wish to squabbling about, but is is not a 'what is correct technically'
issue. It is cleat that probably all of you understand the math, but this
is simply an nomenclature issue.
I don't have any disagreement with this. I just have to keep cautioning
people not to extrapolate it to power. That is, just because the RMS
value of voltage or current is an "effective" or DC equivalent value,
don't think it implies that the RMS value of power must be its
"effective" or DC equivalent value. It's not.
. . .
I am not not trying to prolong the pain (or this thread), it is just that I
was born with a bone in my head that makes it hard for me to give up
explaining some basic concept like this. (yep, it can be a curse) . . .
Egad, another person with the same genetic defect! Welcome!
Roy Lewallen, W7EL
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