UK earthling - was: Dipole-2 different wire sizes?
"Rob" napisał w wiadomości
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Szczepan Bialek wrote:
napisa3 w wiadomo?ci
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Szczepan Bialek wrote:
I was asking on the speed of electrons in the conductor.
No you were babbling about electrons jumping off the end of the antenna
yet again.
You have also been told many times that the speed of the electrons in
the
conductor is less than a slow crawl.
The average speed.
The circuit with an antenna was named "open circuit" before Maxwell.
Maxwell discovered that the current is "prolongated" in the insulator
(displacement current) so the all circuits are "closed".
So at the bonduary the electrons must jump off. And come back.
In each textbooks is wrote that electrons jump off from a conductor and
come
back.
But sometimes this phenomena is not symmetric.
You still have not explained how it is possible that the behaviour
is not symmetric and still there is no nonlinearity in the antenna.
The oscillatory flow of electrons is inherently not symmetric.
Always some of them jump off from the antenna end. VSWR =1 means that all
jumps off.
It should be obvious for you if you see the electrons in the wire.
For Pointing there no electrons. There are only fields around the wire.
He wrote: " Formerly a current was regarded as something traveling along a
conductor, attention being chiefly directed to the conductor, and the energy
which appeared at any part of the circuit, if considered at all, was
supposed to be conveyed thither through the conductor by the current. "
And next: "The aim of this paper is to prove that there is a general law for
the transfer of energy, according to which it moves at any point
perpendicularly to the plane containing the lines of electric force and
magnetic force, and that the amount crossing unit of area per second of this
plane is equal to the product of the intensities of the two forces,
multiplied by the sine of the angle between them, divided by , while the
direction of flow of energy is that in which a right-handed screw would move
if turned round from the positive direction of the electromotive to the
positive direction of the magnetic intensity".
The teachers buy it.
Before Haeviside and Pointing was " something traveling along a conductor".
What do you prefer: electrons or fields?
S*
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