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Old March 14th 07, 06:16 PM posted to rec.radio.amateur.antenna
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Default Gaussian statics law

On Wed, 14 Mar 2007 09:09:27 -0800, Tom Donaly
wrote:
Different texts have Maxwell's equations in different order. What text
did you get this from? Becker has it (in Gaussian CGS units) as
div D = 4\pi\rho (where the backslash indicates multiplication, and D
and rho have the usual meanings. You can add the 't' if you want to, but
it's unnecessary. Also, since you're dealing in 3 dimensions, why not
indicate them as in E(x,y,z), or E(x,y,z,t) (if the time means something
to you)?


I tend to write equations in LaTeX form as most people I exchange
emails with mathematical equations use that for formatting mathematics.
Here, \pi represents the greek letter pi, and \rho is the greek letter
rho. I used x to represent a spatial 3-vector. I could have written
it as (x,y,z) but I did not think this shorthand would cause any
confusion given the context.

The difference between E and D is not important here. If you use D,
then \rho must be interpreted as the so-called "free" charge density.
However, the fundamental field is E, and if you use it the \rho must
be interpreted as the _full_ charge density. The relationship between
E and D can be very complex and may well depend upon the strength of
the applied field E. For simple materials a linear relationship is
usually assumed, e.g., D = \epsilon E, where \epsilon is the
dielectric constant of the medium. Also even here in this linear
relationship, \epsilon need not be a scalar (a number). It could be a
tensor (a 3x3 matrix), in which case D and E would not have the same
direction.

--John
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Old March 14th 07, 07:26 PM posted to rec.radio.amateur.antenna
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Default Gaussian statics law

On Mar 13, 6:33 pm, Richard Clark wrote:
On 13 Mar 2007 22:15:37 GMT, (John E. Davis)
wrote:

I do not understand your comment.


Hi John,

It was rather explicit. To have disputed Dave's assertion with
additional material that substantiated him, makes for a rather strange
reading of Feynman.


.. You can bow out once again,
of course, and become a martyr instead. Or you can indulge us with a
dialog with Art.


I would think this comment applied equally to Dave.


Derek

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Old March 14th 07, 07:40 PM posted to rec.radio.amateur.antenna
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Default Gaussian statics law

John E. Davis wrote:
On Wed, 14 Mar 2007 09:09:27 -0800, Tom Donaly
wrote:
Different texts have Maxwell's equations in different order. What text
did you get this from? Becker has it (in Gaussian CGS units) as
div D = 4\pi\rho (where the backslash indicates multiplication, and D
and rho have the usual meanings. You can add the 't' if you want to, but
it's unnecessary. Also, since you're dealing in 3 dimensions, why not
indicate them as in E(x,y,z), or E(x,y,z,t) (if the time means something
to you)?


I tend to write equations in LaTeX form as most people I exchange
emails with mathematical equations use that for formatting mathematics.
Here, \pi represents the greek letter pi, and \rho is the greek letter
rho. I used x to represent a spatial 3-vector. I could have written
it as (x,y,z) but I did not think this shorthand would cause any
confusion given the context.

The difference between E and D is not important here. If you use D,
then \rho must be interpreted as the so-called "free" charge density.
However, the fundamental field is E, and if you use it the \rho must
be interpreted as the _full_ charge density. The relationship between
E and D can be very complex and may well depend upon the strength of
the applied field E. For simple materials a linear relationship is
usually assumed, e.g., D = \epsilon E, where \epsilon is the
dielectric constant of the medium. Also even here in this linear
relationship, \epsilon need not be a scalar (a number). It could be a
tensor (a 3x3 matrix), in which case D and E would not have the same
direction.

--John


Thanks for explaining that, John. I am unfamiliar with the conventions
of LaTex, obviously (I get my information from books that are generally
older than I am, and I'm not young). I don't have any problem with
Gauss' law being used in a non-static context. It applies, regardless.
That's as far as I go in agreeing with Art, though, since I can't
understand the rest of his theory, at all (but might if I could turn
off the left side of my brain - maybe).
73,
Tom Donaly, KA6RUH
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Old March 14th 07, 08:26 PM posted to rec.radio.amateur.antenna
art art is offline
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Default Gaussian statics law

On 14 Mar, 12:40, "Tom Donaly" wrote:
John E. Davis wrote:
On Wed, 14 Mar 2007 09:09:27 -0800, Tom Donaly
wrote:
Different texts have Maxwell's equations in different order. What text
did you get this from? Becker has it (in Gaussian CGS units) as
div D = 4\pi\rho (where the backslash indicates multiplication, and D
and rho have the usual meanings. You can add the 't' if you want to, but
it's unnecessary. Also, since you're dealing in 3 dimensions, why not
indicate them as in E(x,y,z), or E(x,y,z,t) (if the time means something
to you)?


I tend to write equations in LaTeX form as most people I exchange
emails with mathematical equations use that for formatting mathematics.
Here, \pi represents the greek letter pi, and \rho is the greek letter
rho. I used x to represent a spatial 3-vector. I could have written
it as (x,y,z) but I did not think this shorthand would cause any
confusion given the context.


The difference between E and D is not important here. If you use D,
then \rho must be interpreted as the so-called "free" charge density.
However, the fundamental field is E, and if you use it the \rho must
be interpreted as the _full_ charge density. The relationship between
E and D can be very complex and may well depend upon the strength of
the applied field E. For simple materials a linear relationship is
usually assumed, e.g., D = \epsilon E, where \epsilon is the
dielectric constant of the medium. Also even here in this linear
relationship, \epsilon need not be a scalar (a number). It could be a
tensor (a 3x3 matrix), in which case D and E would not have the same
direction.


--John


Thanks for explaining that, John. I am unfamiliar with the conventions
of LaTex, obviously (I get my information from books that are generally
older than I am, and I'm not young). I don't have any problem with
Gauss' law being used in a non-static context. It applies, regardless.
That's as far as I go in agreeing with Art, though, since I can't
understand the rest of his theory, at all (but might if I could turn
off the left side of my brain - maybe).
73,
Tom Donaly, KA6RUH- Hide quoted text -

- Show quoted text -


Tom,
don,t worry about it! A poster has stated it was invented years ago.
I haven,t found it in any of my books so perhaps he will tell you
where
you can look at it. I assume my patent will now be turned down when
it is pointed out where the Gaussian antennas can be seen. When he
describes it
it to you then it should be much easier for you to understand the
logic behind it
and to determine whether it is all a todo about nothing. As for me I
think
the subject can be said as proven, albiet over 100 years or more ago
and the whole subject
started by that blithering idiot, sycopath and all those other phrases
can now
seen as closed. I will hang around a bit to see what I could have
been if
only I had been born 100 or 200 years ago where somebody said I will
have all
the manufacturers knocking on my door. Maybe that inventor of the
gaussian array left me a morsel on the cutting room floor which I can
exploit and which I can reveal after the existing Gaussian presence is
revealed by the poster. But that still leaves the question why haven't
ham
radio users not picked up the slack and tried them? Maybe it is the
'not invented in my town' thinking and where their heads still rest in
the sand. I also have this other invention
that I want.............no, I have learned my lesson I will take it to
my grave that would be so much easier.
Art The Englishman

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Old March 14th 07, 09:39 PM posted to rec.radio.amateur.antenna
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Default Gaussian statics law


"Derek" wrote in message
ups.com...
On Mar 13, 6:33 pm, Richard Clark wrote:
On 13 Mar 2007 22:15:37 GMT, (John E. Davis)
wrote:

I do not understand your comment.


Hi John,

It was rather explicit. To have disputed Dave's assertion with
additional material that substantiated him, makes for a rather strange
reading of Feynman.


. You can bow out once again,
of course, and become a martyr instead. Or you can indulge us with a
dialog with Art.


I would think this comment applied equally to Dave.


Derek

i like the post that points out the unnecessary t in the Gauss's law
equation... well done. sri i didn't state that myself, but i have had
better things to do than try to argue with art.




  #96   Report Post  
Old March 14th 07, 10:13 PM posted to rec.radio.amateur.antenna
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Posts: 2,951
Default Gaussian statics law

On 14 Mar 2007 13:26:46 -0700, "art" wrote:

But that still leaves the question why haven't
ham
radio users not picked up the slack and tried them?


Hi Art,

That was done an hundred years ago, and people found better ways.

73's
Richard Clark, KB7QHC
  #97   Report Post  
Old March 14th 07, 10:19 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Mar 2007
Posts: 36
Default Gaussian statics law

On Mar 14, 2:39 pm, "Dave" wrote:


i like the post that points out the unnecessary t in the Gauss's law
equation... well done. sri i didn't state that myself, but i have had
better things to do than try to argue with art.



As I remember it you were arguing with John.


Derek

  #98   Report Post  
Old March 14th 07, 10:42 PM posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Jul 2006
Posts: 797
Default Gaussian statics law


"Derek" wrote in message
ups.com...
On Mar 14, 2:39 pm, "Dave" wrote:


i like the post that points out the unnecessary t in the Gauss's law
equation... well done. sri i didn't state that myself, but i have had
better things to do than try to argue with art.



As I remember it you were arguing with John.


Derek

i was probably arguing with a couple of them... all the blabbering looks the
same after a while.


  #99   Report Post  
Old March 15th 07, 06:52 AM posted to rec.radio.amateur.antenna
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Posts: 625
Default Gaussian statics law

On Mar 9, 2:11 pm, John Smith I wrote:
Cecil Moore wrote:
wrote:
EM waves depart when energy is applied, not particles.


Quantum Electrodynamics tells us that EM waves consist
of photons which are particles.
--
73, Cecil, w5dxp.com


So, which is the real question:

1) Why do waves act like particles?

--OR--

2) Why do particles act like waves?

JS
--http://assemblywizard.tekcities.com


When a field is traveling at/near the speed of light it has mass(acts
as a particle) slower and it is a wave. EM lives on the hairy edge of
both worlds. vAt least thats what my Phd girlfriend told me once. Who
knows though, she was pretty weird.

JIMMIE

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Old March 15th 07, 05:22 PM posted to rec.radio.amateur.antenna
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Posts: 1,154
Default Gaussian statics law

JIMMIE wrote:

...
When a field is traveling at/near the speed of light it has mass(acts
as a particle) slower and it is a wave. EM lives on the hairy edge of
both worlds. vAt least thats what my Phd girlfriend told me once. Who
knows though, she was pretty weird.

JIMMIE


Yes. Just thinking about this one aspect can keep me up for hours from
a restful sleep ...

Regards,
JS
--
http://assemblywizard.tekcities.com
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