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Old December 26th 07, 05:11 PM posted to rec.radio.amateur.antenna
Cecil Moore[_2_] Cecil Moore[_2_] is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 3,521
Default Standing-Wave Current vs Traveling-Wave Current

Roy Lewallen wrote:
The voltage and current are, of course, 90 degrees out of phase, ...

p(t) = v(t) * i(t) = 0.01 * sin(wt - 180) * cos(wt - 180)
= 0.005 * sin(2wt)


Those are not watts, those are volt*amps. Therefore that's
not real power. Real power is:

p(t) = v(t) * i(t) * cos(90) = ZERO
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73, Cecil http://www.w5dxp.com