Re: Basic Question

On Sep 5, 12:22=A0pm, "extremesoundandli...@[EMAIL PROTECTED]
"
<extremesoundandli...@[EMAIL PROTECTED]
> wrote:
> On Sep 5, 10:15=A0am, j...@[EMAIL PROTECTED]
 wrote:
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>
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> > EskWI...@[EMAIL PROTECTED]
 wrote:
> > > In sci.physics.electromag, j...@[EMAIL PROTECTED]
 wrote:
> > >> EskWI...@[EMAIL PROTECTED]
 wrote:
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> > >> > Ummm....using any wire of any thickness and a given resistance
per=
 unit of
> > >> > length, why is it that more voltage will yield more current? Is
it=
 a
> > >> > matter of velocity of electron flow? =A0
>
> > >> Because E=3DIR which is basic Ohm's Law.
>
> > > That I know. =A0The question is why. =A0
>
> > You mean why does Ohm's Law work?
>
> > The simple answer is you start with Maxwell and work your way into
Ohm.
>
> > It was a homework problem and extended classroom discussion when I
went=
 to
> > school. Feel free to have the experience.
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> > You can't get there without math.
>
> > >> The magnetic field propogates at c.
>
> > > I thought that electromagnetic fields propogated at C only in free
sp=
ace. =A0
> > > Doesn't a wire provide significant resistance?
>
> > Yes, but resistance has nothing to do with the velocity of
propagation,
> > that is determined by the dielectric constant.
>
> > The velocity of propagation or velocity factor is a parameter that
> > characterizes the speed of an electomagnetic wave through a medium.
>
> > The VOP of free space is 1.
>
> > The VOP of a medium is the reciprocal of the square root of the
dielect=
ric
> > constant of the medium.
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> > For a bare wire in air the VOP is about 0.99 as the dielectic constant
> > of air is about 1.0005.
>
> > For a wire covered with solid polyethylene the VOP is about 0.66 as
> > the dielectric constant of polyethylene is about 2.25.
>
> > > Are you saying that low voltage electricity travels at the same
veloc=
ity
> > > as high voltage electicity?
>
> > Yes, the velocity of propagation depends only on the dielectric
constan=
t
> > of the propagation medium.
>
> > --
> > Jim Pennino
>
> > Remove .spam.sux to reply.
>
> dielectric constant can vary due to tempature and pressure as well- Hide
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quoted text -
>
> - Show quoted text -

Yes, the velocity of propagation depends only on the dielectric
constant
of the propagation medium

suseptibilty of the medium at zero frequency also plays a role in the
propagation