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krw@att.bizzzzzzzzzzzz
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On Mon, 09 Apr 2012 06:43:38 GMT, Chiron
<chiron613.no.spam.@no.spam.please.gmail.com> wrote:
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<chiron613.no.spam.@no.spam.please.gmail.com> wrote:
Some use pedantry to attempt to show how "brilliant" they are. It's one ofOn Sun, 08 Apr 2012 21:24:29 -0700, Bob Myers wrote:
On Sunday, April 8, 2012 6:57:45 PM UTC-6, Chiron wrote:
On Sun, 08 Apr 2012 20:24:27 -0400, krw@att.bizzzzzzzzzzzz wrote:
What is the meaning of power squared?
What is the meaning of voltage squared?
I'm not trying to claim that there *is* any such thing as RMS power;
just wondering why such a thing would be impossible.
Obviously it's not - "RMS" (root-mean-square) is simply a mathematical
means for getting a meaningful "average" value, particularly for cases
where the actual "average" would be zero (as in the case of a
zero-offset sinusoid). You can most certainly square any function,
average it over a suitable period, and then take the square root of that
mean value, which would be the "RMS" value of that function. The only
remaining question is whether or not it's useful to do so in any given
case.
So you could certainly calculate an "RMS" value for power, or for
voltage, or for the Dow Jones average over the past year if you like.
But to get back to the original question - I've also heard the term "RMS
power" intended (rather sloppily, but it was at least understood) to
mean "true power." Not exactly the best use of that term, but generally
no one gets too bent out of shape about it other than the sorts of
pedants we see exemplified in this thread.
Bob M.
Actually, that was what my vague wonderings were trying to get at. I
remembered that RMS had *something* to do with values going negative; but
I couldn't remember the details. Of course, what I was groping for only
applied to the values that tended to average out to zero, so I was still
pretty wide of the mark... Oh, well.
It's kind of strange to find pedantry in an electronics group. Back in
the day (late seventies, early eighties) we were happy if we were within
10% of reality.
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