# Re: Displacement current

Glenn -

The "displacement current" subject is a non-issue because these currents
do not exist. Displacement currents is a misunderstanding of Maxwell's
"electric displacement" which he used to describe the transfer of electrical
energy thru conductors or dielectrics such as a vacuum, space, air, etc.

As I have mentioned before on the List my understanding is that there are
only two methods of electrical energy transfer, by currents, or by
radiation. The  currents flow thru conductors in the form of moving charges
and are governed by Ohm's law plus other laws. Radiation is in the form of
electromagnetic waves and governed by the laws of wave mechanics plus the
energy equation  E = hf  where E is energy, h is Plank's constant, and f is
the frequency.

For example, with a Tesla coil the equation says the higher the frequency
the greater the energy in the radiation from the coil. The electrical energy
(joules) in the Tesla coil is in the form of currents while in the
conductors, toroid, and spark. When the electrical energy (photons) leaves
the coil it leaves as electromagnetic radiation in the form of electrical
fields around the coil. These electrical fields can be measured.

The problem that coilers have now is identifying these fields. For
example, does Terry's antenna measure the near or far field when it is
placed near the coil? I believe the far field is the electromagnetic field
that is normally measured by a wire placed in the path of the wave and shows
as a volts per meter on the instrument. The near field would be the magnetic
field due to the current in the coil as per Faraday. But when the wire is
near the coil and energizes incandescent lamps what field are we dealing
with?

There is obviously much more to consider.

John Couture

--------------------------

At 11:46 AM 3/8/99 -0700, you wrote:
>Original Poster: Glenn <gcerny-at-megsinet-dot-net>
>
>I find this thread most interesting. While
>not directly related to spark lenght, it has
>provided food for though about how energy
>transfers through  the media.
>My thoughts have been aroused.