Marcel Duchamp wrote:
> On 1/8/2010 2:00 PM, ivp wrote:
> > If two lengths of resistance wire are in parallel but not in intimate
> > contact, they will be as paralleled resistors. But what if they are in
> > contact, eg twisted together ? That make a large number of
> > paralleled segments in series wouldn't it ?
> >
> > Making some low-value sense resistors with Cuprothal wire, which
> > is 6 ohms/metre. If I parallel 4 strands (=>  1.5R/m) then that's 40mm
> > to make a 60mR resistor, rather than 10mm of the single strand. I'd
> > rather work with 40mm than 10mm
> 
> Yes, that would make a large number of paralleled segments in series. 
> And the total resistance will be the same as if the two wires did not 
> touch anywhere but the ends.  So you are good to go.

Another way to think about it: If the wire is uniform, the voltage
distribution along each of the strands will be identical, so even if
they're in contact at one or more points, no current will flow between
them.

-- Dave Tweed
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