On Sep 5, 6:48=A0am, "extremesoundandli...@[EMAIL PROTECTED]
"
<extremesoundandli...@[EMAIL PROTECTED]
> wrote:
> 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
=
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
>
> > > > Why, for example, does one needs to use thicker wires on the low
si=
de 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. =A0
>
> > > The power in and power out of a transformer (ignoring losses) are
equ=
al,
> > > but the voltages aren't, which is normally why one is using a
transfo=
rmer
> > > in the first place.
> > > So, for a fixed amount of power, the current is higher on the low
sid=
e,
> > > 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
=
lower,
> > > > so by applyng Ohm's law, we see that....
>
> > > > Instead, I'm asking what is going on at a particle level. =A0And
> > > 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
assoc=
iated
> > > > magnetic field propogates down the length of the wire at a greater
> > > > velocity at higher voltage. =A0
> > > 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
spac=
e. =A0
> > Doesn't a wire provide significant resistance?
>
> > Are you saying that low voltage electricity travels at the same
velocit=
y
> > 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.
> > =A0 =A0 =A0 =A0 -- 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 =A0the properties of the wire itself can answer your
> initial question.
>
> All carbon nanotube wire is a =A0very 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.-
Hid=
e quoted text -
>
> - Show quoted text -
so less power is required to move the same amount of electrons through
a given point.
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