Re: Is the Superposition Principle invalid?

Cecil Moore wrote:
Gene Fuller wrote:
Even if you could separate the forward and reverse waves the Poynting vector energy calculation would still come out to exactly zero for each component as well as the sum of the components.

Forward and reflected waves are easily separated by a
circulator so their existence is difficult to deny.

So net energy equals zero? So what! We are NOT discussing net
energy here. We are discussing the forward Poynting vector
and the reflected Poynting vector as described in "Fields and
Waves ...", by Ramo and Whinnery. The Superpositon Principle
gives us permission to do so and the final result is identical
to any other valid analysis. Why are you guys so irrationally
afraid of the wave reflection model? What is your ulterior
motive in denying the existence of reflected waves during
steady-state? It has seemingly turned into a steady-state
religion administered by the steady-state high priests.


Cecil,

I guess I was not quite clear. I don't care if you are talking net energy, gross energy, with or without circulators, or anything else. As long as there are no sources or sinks of energy in the region of interest, the Poynting vector tells you absolutely nothing about energy balance or conservation of energy.

You could have a completely incorrect analysis of forward and reverse waves, and the Poynting analysis will not reveal the error. The required integral will still come out to exactly zero.

Radio amateurs and radio charlatans love to talk about Poynting vectors, but it is obvious that most of those folks simply don't understand the full picture. Just forget about ExB (or more commonly, ExH). It is completely useless in support for the typical RRAA discussions.

73,
Gene
W4SZ
.

Relevant Pages

  • Re: Is the Superposition Principle invalid?
    ... the forward and reverse waves the Poynting vector energy calculation would still come out to exactly zero for each component as well as the sum of the components. ... Waves ...", by Ramo and Whinnery. ...
    (rec.radio.amateur.antenna)
  • Re: Superposition
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    (rec.radio.amateur.antenna)
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