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Old January 25th 08, 12:15 AM 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 Where's the energy? (long)

Jim Kelley wrote:
I guess you didn't notice the thing about the square of the sum of two
numbers being four times as great as the square of one of the numbers.
It simply means, for example, that a doubling in voltage is a
quadrupling in power. It doesn't mean there's "extra" energy anywhere.


On the contrary, constructive interference cannot happen
without that "extra" energy sucked up from destructive
interference (or from a local source). That's what you
are completely missing. Constructive interference between
two waves requires more energy than exists in those two
component waves. In the absence of a local source, another
two waves *must* be engaging in destructive interference
at the same time in order to supply the constructive
interference.

Conservation of energy doesn't allow for there to *be* extra energy in
the first place!


Therefore, those bright rings are just an illusion and
don't contain more than the average energy in the two
superposed waves. I guess that's your story and you
are sticking to it.
--
73, Cecil http://www.w5dxp.com