On Sep 5, 5:50 am, EskWI...@[EMAIL PROTECTED]
wrote:
> In sci.physics.electromag, j...@[EMAIL PROTECTED]
wrote:
> > EskWI...@[EMAIL PROTECTED]
wrote:
>
> > > Ummm....using any wire of any thickness and a given resistance per
un=
it of
> > > length, why is it that more voltage will yield more current? Is it a
> > > matter of velocity of electron flow? =20
> > Because E=3DIR which is basic Ohm's Law.
>
> That I know. The question is why. =20
>
> > > Why, for example, does one needs to use thicker wires on the low
side=
of a
> > > transformer, while on the high side, one can use thinner wires?
> > Because P=3DI^2 R and P=3DEI.
>
> That I already know. =20
>
>
>
>
>
> > The power in and power out of a transformer (ignoring losses) are
equal=
,
> > but the voltages aren't, which is normally why one is using a
transform=
er
> > in the first place.
> > So, for a fixed amount of power, the current is higher on the low
side,
> > hence thicker wire to carry that current and less loss in the winding
> > due to I^2 R losses.
> > On the high side, keeping in mind the power is fixed, the current is
> > lower hence you don't need wire as thick as the low side.
> > > I'm not asking to be told that the resistance of the thick wire is
lo=
wer,
> > > so by applyng Ohm's law, we see that....
>
> > > Instead, I'm asking what is going on at a particle level. And
> > Ohm's law works at the macro level and answers the questions.
> > Analysis at the particle level doesn't really address the questions
> > you asked.
> > > additionally, as a corollary question, I'm asking whether the
associa=
ted
> > > magnetic field propogates down the length of the wire at a greater
> > > velocity at higher voltage. =20
> > No.
> > The magnitude of the magnetic field is a function of current.
> > The magnetic field propogates at c.
>
> I thought that electromagnetic fields propogated at C only in free
space.=
=20
> Doesn't a wire provide significant resistance?
>
> Are you saying that low voltage electricity travels at the same velocity
> as high voltage electicity?
>
> --
> The whole problem with the world is that fools and fanatics are always
so
> certain of themselves, but wiser people so full of doubts.
> -- Bertrand Russel- Hide quoted text -
>
> - Show quoted text -
The properties of the wire itself can increase the efficiency of
electronic flow and not as much power is required to move electrons
through your wire that's why I suggested carbon wire due to its
molecular structur the properties of the wire itself can answer your
initial question.
All carbon nanotube wire is a very good thermal conductors along the
tube, exhibiting a property known as "ballistic conduction," but good
insulators laterally to the tube axis. It is predicted that carbon
nanotubes will be able to transmit up to 6000 watts per meter per
kelvin at room temperature; compare this to copper, a metal well-known
for its good thermal conductivity, which only transmits 385 W=B7m-1=B7K-1.
The temperature stability of carbon nanotubes is estimated to be up to
2800 degrees Celsius in vacuum and about 750 degrees Celsius in air.
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