Real time proof of Poyntings vector
"I have spent a considerable amount of time in researching the above
subject
as a result of some comments made regarding Gauss's law of Statics
and its connection to the above Poynting's Vector. I have not yet
found
a description of an actual proof similar to described by the Gaussian
Antenna
and have found a number considerable number of " attempts" to provide
such a proof on the internet.
The problem that you have is that the Poynting Vector does not exist as
such, so it cannot be proved. It is nothing more than a mathematical nicety
that happens to yield a vector product that happens to be in the direction
of propagation. It is possible to devise an infinite number of similar
vectors that equally well (or better in some cases) describe the energy flow
through a surface.
There are plenty of derivations of the mathematical relevance of the
Poynting Vector available.
The Poynting Vector is favoured because it is mathematically simple and
describes energy flow adequately in a non-static case.
73
Jeff
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