Re: Basic Question

On Sep 5, 12:45 pm, j...@xxxxxxxxxxxxxxxxxxxx wrote:
extremesoundandli...@xxxxxxxxx <extremesoundandli...@xxxxxxxxx> wrote:
On Sep 5, 10:15?am, j...@xxxxxxxxxxxxxxxxxxxx wrote:
EskWI...@xxxxxxxxxxxxxxxxxxx wrote:
In sci.physics.electromag, j...@xxxxxxxxxxxxxxxxxxxx wrote:
EskWI...@xxxxxxxxxxxxxxxxxxx wrote:

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? ?

Because E=IR which is basic Ohm's Law.

That I know. ?The question is why. ?

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.

You can't get there without math.

The magnetic field propogates at c.

I thought that electromagnetic fields propogated at C only in free space. ?
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 dielectric
constant of the medium.

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 velocity
as high voltage electicity?

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

--
Jim Pennino

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dielectric constant can vary due to tempature and pressure as well

For some things, yes, but so what?

The velocity of propagation depends only on the dielectric constant of
the propagation medium, whatever the dielectric constant may be.

--
Jim Pennino

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If dielectric material is a measure of how easily it polarizes in
response to an electric field. Then the electric permittivity of the
material and thus is influenced by many other phenomena in that
medium, from the velocity at which the current travels. And its
constant can change due to other outside phenomena so the dielectric
constant in a vacuum is true to say that velocity of propagation
depends only on the dielectric medium in a vacuum but he is doing the
expeirament here on earth so im not comfortable with your term only.

.

Relevant Pages

  • Re: Basic Question
    ... why is it that more voltage will yield more current? ... matter of velocity of electron flow? ... that is determined by the dielectric constant. ... characterizes the speed of an electomagnetic wave through a medium. ...
    (sci.physics.electromag)
  • Re: Basic Question
    ... why is it that more voltage will yield more current? ... matter of velocity of electron flow? ... that is determined by the dielectric constant. ... characterizes the speed of an electomagnetic wave through a medium. ...
    (sci.physics.electromag)
  • Re: Basic Question
    ... matter of velocity of electron flow? ... characterizes the speed of an electomagnetic wave through a medium. ... the dielectric constant of polyethylene is about 2.25. ...
    (sci.physics.electromag)
  • Re: Basic Question
    ... characterizes the speed of an electomagnetic wave through a medium. ... the dielectric constant of polyethylene is about 2.25. ... of the propagation medium. ... the velocity of propagation depends only on the dielectric ...
    (sci.physics.electromag)
  • Re: Basic Question
    ... Yes, but resistance has nothing to do with the velocity of propagation, ... The VOP of a medium is the reciprocal of the square root of the dielectric ... the dielectric constant of polyethylene is about 2.25. ...
    (sci.physics.electromag)