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Re: Tesla's Wireless Power Transmission ==> was Re: Non-tech Qu
Ben-
The one over r squared is just spherical spreading spreading in three
dimensions).
It is just continuum mechanics.
That "law" is broken all the time when spreading is constrained to two
dimensions, such as it sometimes is by atmospherics and the ground (or
between two planes). In that case, it becomes cylindrical spreading or one
over r. If the radiation is ducted by atmospherics or by a waveguide, then
it is constrained to one dimension and losses drop to even less than than
one over r. It is just the geometry of the antenna and anything acting
like a waveguide.
Now, going the other way, intensity can fall off even faster than one over
r squared (even faster than three dimensional spreading) when the radiation
is multipole, such as quadrapole. This is due to cancellation of
neighboring poles at a distance.
All this is not just related to electromagnetic waves. It is true for
acoustics, also.
Dick