On 27 Jun, 17:21, John C. Polasek <jpola...@[EMAIL PROTECTED]
> wrote:
> On Fri, 27 Jun 2008 06:35:23 -0700 (PDT), blackhead
>
>
>
>
>
> <larryhar...@[EMAIL PROTECTED]
> wrote:
> >On 26 Jun, 03:25, John C. Polasek <jpola...@[EMAIL PROTECTED]
> wrote:
> >> On Wed, 25 Jun 2008 18:32:46 GMT, "Bill Miller"
>
> >> <billmillerkt...@[EMAIL PROTECTED]
> wrote:
>
> >> >"Timo A. Nieminen" <t...@[EMAIL PROTECTED]
> wrote in message
> >> >news:Pine.WNT.4.64.0806240535450.1160@[EMAIL PROTECTED]
> >> >> On Mon, 23 Jun 2008, Bill Miller wrote:
>
> >> >That leaves hordes of non PG students still believing this rubbish.
A=
nd it
> >> >begs the question of why, in UG cl*****, the instructors don't say
> >> >*something* about how theses two parameters don't cause each other,
b=
ut that
> >> >they always appear simultaneously. I suspect its because the
instruct=
ors
> >> >don't know it!
>
> >> I fervently hope you're not teaching anyone. You're too ignorant to
be
> >> in the business of physics which is that of discerning cause and
> >> effect. Instead of denying cause and effect, you should be analyzing
> >> for the underlying science.
>
> >> >Is there a single UG EM textbook that correctly categorizes the
relat=
ion****p
> >> >between E and H? Even ONE?
>
> >> Tell us, omniscient one, what exactly what is this precious
> >> relation****p, of which you are evidently the exclusive franchisee?
>
> >> Here's how I think it works: Volts applied to a coil build up H
> >> ampturns/meter which when multiplied by mu store momentum B in
> >> webers/m^2. Upon opening the circuit, momentum B divided by mu
> >> generates a sizeable voltage back at the original terminals. The
field
> >> B is successively the sink and the source. Yes V causes B and B
causes
> >> V.
>
> >> >Cheers, Bill
>
> >> John Polasek
>
> >A charge is the source of E and H which are orthogonal and propagate
> >independently from it as given by the Lienard-Wiechert field
> >equations. I think that's all Bill is saying which isn't wrong, is it?
>
> You are right; retardation is adequately represented by the
> Lienard-Wiechert field, which I also see referenced in my 1962
> Panofsky Philips. They are much cleaner and simpler than Jefimenko's
> which can be seen in Wiki.
>
> For Lienard, yes, if you postulate a moving charge it will have
> complex field effects. But in free space the only current J would be
> Ddot and there is no overt charge density to put in Jefimenko's
> equation.
> This topic is of little practical effect, retardation being a very
> slippery item, and there is enough other disinformation going around
> to bother with these sophomoric maunderings.
>
> For example, it is unconscionable that there are physicists today
> still embedded in cgs, a legacy from their professors with these
> consequences:
> =A0 =A0 =A0 =A0 1. They have given up the coulomb in favor of the esu.
> =A0 =A0 =A0 =A0 2. It is not possible to assign units to equations e.g.:
> =A0 =A0 =A0 =A0 =A0 =A0 =A0D =3D E =A0 =A0 =A0 =A0 =A0 =A0 =A0please,
ass=
ign units
> =A0 =A0 =A0 =A0 3. they gave up capacitance which should be coulomb/volt
=
(or
> farads) in favor of
> =A0 =A0 =A0 =A0 4. capacitance in centimeters, a clue to the naive "peas
=
on a
> knife" view of electrostatics.
> =A0 =A0 =A0 =A0 5. It is not possible in cgs to intelligently discuss a
v=
acuum
> capacitor.
>
> Enough. More dismal is the idea that most students do not even know
> the difference between cgs and rmks or SI which have assigned the
> properties of eps0 and mu0 to the vacuum.
>
> The main idea is that there are forces that can store energy in the
> vacuum which energy then turns around and becomes a source itself in a
> completely reciprocal fa****on. And this, without the intervention of
> charges.
> John Polasek- Hide quoted text -
>
> - Show quoted text -
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