EskWIRED@[EMAIL PROTECTED]
wrote:
> In sci.physics.electromag, extremesoundandlight@[EMAIL PROTECTED]
> wrote:
>
>> use carbon nano fiber as the wire its thin and can su****t a
>> tremedousely high current and voltage witch is directly pro****tional
>> and inversly pro****tional to resistance.
The above is babbling nonsense.
> 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.
> 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=I^2 R and P=EI.
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 transformer
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
lower,
> 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 associated
> magnetic field propogates down the length of the wire at a greater
> velocity at higher voltage.
No.
The magnitude of the magnetic field is a function of current.
The magnetic field propogates at c.
--
Jim Pennino
Remove .spam.sux to reply.
|
