On 31 Oct 2005 09:35:09 -0800, "lu6etj" wrote:

PS: I have another physical doubt, if you can help me.
Can a real DC current radiate electromagnetic energy?.
It is not captious [capricious] or cheat [trick] question. I think yes, but I don't want to
condition your answers with my hypotesis.

Hi Miguel,

A "real" DC current?

Yes.

A "real" DC current (at some point in time) starts - and stops. It is
at each of these two points that the step change offers radiation. The
"time" it takes to go from one level to the other defines that
frequency, and its harmonics.

A "perfect" DC current has always been on, and will always be on. No
change, no radiation.

73's
Richard Clark, KB7QHC

Hi, all folks and Dear Richard (Is right this salutation?)

Thanks for your patience to me...

Imagine a simple DC generator in steady state, the closing circuit
(sure, with a serie resistance, no short), forms a physical loop, the
current travel accross it in a uniform circular movement, therefore
charges have a centripet acceleration = charges accelerated =
electromagnétic radiation.

Electron orbiting nucleus problem - quantum theory solution.

Am I in the correct way?. DC current produce electromagnetic radiation
(on solenoid more, of course)?

I never read something in such a sense (except in atomic theory, of
course), but I find reasonable to suppose it.

Thanks in advance

Miguel Ghezzi (LU 6ETJ)
------------------------------------------------------------------------------------------------------------

Hola a todos y estimado Richard. (es correcto saludar asi?)

Gracias por su paciencia.

Imagine un simple generador de CC en regimen estacionario, el circuito
que lo cierra (por supuesto con una resitenci, no en corto) forma un
lazo físico. La corriente viaja a traves de el en un movimiento
circular uniforme, por lo tanto las cargas poseen una
aceleracion centripeta = cargas aceleradas = radiacion
electromagnetica...

El problema del electron orbitando el nucleo - solucion de la teoria
cuantica.

Estoy en lo correcto? La corriente continua produce radiacion
electromagnetica (mas en un solenoide, por supuesto)?

Nunca lei nada en tal sentido (excepto en la teoria atomica, por
supuesto) pero me parece razonable suponerlo

Miguel Ghezzi (LU 6ETJ)

On 31 Oct 2005 12:07:29 -0800, "lu6etj" wrote:

Hi, all folks and Dear Richard (Is right this salutation?)

Hi Miguel,

It is fine.

Imagine a simple DC generator in steady state, the closing circuit
(sure, with a serie resistance, no short), forms a physical loop, the
current travel accross it in a uniform circular movement, therefore
charges have a centripet acceleration =3D charges accelerated =3D
electromagn=E9tic radiation.

You are using acceleration in its usual sense. Unfortunately, it is
based on a poor description for radiation. It is a poor description
in English, or any language.

Electron orbiting nucleus problem - quantum theory solution.

Circular motion is always acceleration, and orbital electrons are
always in circular motion. They are not always radiating. This one
observation is enough to invalidate the general description of
accelerating electrons causing radiation (it takes more than that).

An orbital electron only radiates when it changes orbital levels to a
LOWER orbit. Read about deBroglie waves. When an Hydrogen electron
in the 3rd orbital falls (acceleration) to the 2nd orbital, it
radiates a photon with a wavelength of 653 nM. You see this every
night with Neon signs.

Am I in the correct way?. DC current produce electromagnetic radiation
(on solenoid more, of course)?

No.

I never read something in such a sense (except in atomic theory, of
course), but I find reasonable to suppose it.

Reasonable, as I have described above, but not logical.

73's
Richard Clark, KB7QHC

Richard Clark wrote:
An orbital electron only radiates when it changes orbital levels to a
LOWER orbit.

His question was about a conductive loop RF antenna.
RF radiation from an antenna comes from free electrons. Their
associated photon energy levels are correlated to the frequency
of the excitation energy, not to changes in atomic orbits.
--
73, Cecil http://www.qsl.net/w5dxp

Hi Richard

Thank you for your answer.

You are quite right Richard, this is the great postulate of Bohr, but
from:

physics.indiana.edu/~sg/p641/chap2.ps

I have extracted this paragraph (rememember that I did study from books
in spanish, so I had to search the web to find a suitable english
references.)

"...Some physicists of the time did not at first believe in
Rutherford's model
of the atom because, classically, such a model is unstable. The
argument is as
follows: Electrons in orbits around a nucleus undergo acceleration. But
accelerating charged particles emit electromagnetic radiation, losing
energy. Therefore,
electrons orbiting a nucleus should lose energy and spiral into
nucleus.
Then in 1913 Bohr solved the problem by simply postulating that
electrons
move around the nucleus in certain stationary orbits without emitting
radiation.
According to Bohr¡s model electrons emit radiation as photons only
when making
a transition from one stationary orbit with a higher energy to another
stationary
orbit with a lower energy."

Bohr's postulate would not invalidate the postulate of the classic
electromagnetism that a accelerated charge irradiates energy in
classical conditions. Their postulate refers to an electron in an
atomic orbital, a typical quantum situation, the electrons in a
circular wire would be being part of a classic macroscopic system, (I
think).
In such a case, would not emit energy, according to that pointed out in
the cited Indiana's university text ?

I can think a more elaborated example of Direct Current to avoid
derived issues of the electronic movement in a complicated crystalline
structu An electron (or current of electrons) inside a magnetic
field in the vacuum, just as in a cyclotron...

Would it be rightfully an Direct Current?.
Does it fulfill the postulates of the classic physics?
Does it irradiate electromagnetic energy?

For these reasons, I think that DC irradiates electromagnetic energy (a
very, very, very little quantity, of course. This ponderings rises in
my mind from a friend's question about an eternal current in a
superconductor ring.

What do you think about?

Thank you very much for your corrections to my translations...

Miguel Ghezzi (LU 6ETJ)
---------------------------------------------------------------------------------------------------------

Hola Richard.

Gracias por tu respuesta.

Tienes razon Richard, ese es el gran postulado de Bohr, pero de:

physics.indiana.edu/~sg/p641/chap2.ps

Extraje este parrafo (recuerda que yo estudie de libros en espaniol de
manera que tuve que buscar en la web para encontrar referencias
adecuadas en ingles).

[Original english text not translated...]

El postulado de Bohr no invalidaría los postulados del
electromagnetismo clasico que una carga acelereada irradia energia en
condiciones clasicas. su postulado se refiere a un electron en un
orbital atomico, una típica situacion cuantica. Los electrones en un
conductor circular estarían formando parte de un sistema macroscopico
clasico, creo.
En tal caso, no emitirian energia de acuerdo a lo senialado en el texto
de la Universidad de Indiana citado?
Puedo pensar en un ejemplo mas elaborado de corriente continua para
evitar las cuestiones derivadas del movimiento electronico en una
complicada estructura cristalina: Un electron (o corriente de
electrones) dentro de un campo magnetico en el vacio, como en un
ciclotron.

Sería legitimamente una corriente conínua?
Cumple con los postulados de la fisica clasica?
Irradia energia electromagnetica?

Por estas razones creo que una CC irradia energia electromagnetica (una
muy, muy, muy pequenia cantidad, por supuesto). Estas cavilaciones
surgen en mi mente a partir de la pregunta de un amigo acerca de una
corriente eterna en un anillo superconductor.

Que piensas?

Miguel Ghezzi (LU 6ETJ)

On 31 Oct 2005 19:02:35 -0800, "lu6etj" wrote:
What do you think about [it]?

Thank you very much for your corrections to my translations...

Hi Miguel,

You do very well with English.

If you wish to be very, very, very specific, then yes DC will radiate.

Let's take something a little more practical than a cyclotron - the
monitor you are looking at to read this. The CRT is accelerating an
electron to strike a phosphor to illuminate a pixel. We will neglect
that light radiation as not being part of the discussion.

That electron will be accelerated by a field of some 20KV. What is
its frequency?
34.6 exaHertz
the wavelength of roughly 1/10 the distance of an electron orbit
around a Hydrogen atom.

Now, for something completely different. Does a car driving 40
KM/Hour down the road radiate? If you wish to be very, very, very
specific, then yes the car will radiate by the same principle at
5 zetta-yottaHertz

73's
Richard Clark, KB7QHC

Hi Richard

Tanks for your last answer.

Hi hi, well, my friend was very, very very insistent also with his
superconducting and eternal current holder "golden ring"...

I will try learn more about [it] ;) (I have been hard working for
thirty years, and till now, I haven't any time to meditate in all these
beautiful things).

I am very pleased to know you, Richard (my other ham friends it isn't
"very interested" in this type of "exotic questions"... :)

I can see this usenet group always talk about very interesting topics,
with great knowledge and good "ham spirit".

73's

Miguel Ghezzi (LU 6ETJ)

But what if it was rented from Avis?

"Richard Clark" wrote in message specific, then yes
the car will radiate by the same principle at
5 zetta-yottaHertz

73's
Richard Clark, KB7QHC