Actually, there is a slight error in these calculations. Every cable, wire,
circuit board conductor, waveguide, optical fibre, etc. offers a slight
delay to a propagating electrical signal traveling along the wire. This
delay is called the velocity factor.
Learn more here: http://en.wikipedia.org/wiki/Wave_propagation_speed
For example, in a coaxial cable, the VF is usually 0.66 or so, which means
when calculating length for an application based on the speed of light, you
assume the speed of light is reduced by about a third. Manufacturers of
these cables supply the VF as a spec.
Hee hee!
== Alex in Maine
"The Blue Mainie," 1960 Austin Healey 3000 BT7
"Conkling," 1946 M.G. TC #1321
Former owner 1957 A-H 100-6, 1967 A-H BJ8,
1965 MG Midget
http://home.roadrunner.com/~alexmm
----- Original Message -----
From: "Richard Ewald" <richard.ewald at gmail.com>
To: "John Sims" <ahbn6 at verizon.net>
Cc: "Healey List" <Healeys at autox.team.net>
Sent: Thursday, May 31, 2012 2:43 PM
Subject: Re: [Healeys] ingnition leads
> Yes it is, but I didn't use a light year, I used the speed in miles per
> hour and converted to inches per second. From there is it trivial to see
> how long it takes to cover 1". :-)
> The time required to cover 2, 3 and 4 inches will be left as an exercise
> to
> the student.
> Rick
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