Re: LC III

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Paul Nicholson <paul@xxxxxxxxxxxxxxxxxxx>

Jared wrote:

> These coils should not function according to your velocity
> factor theory, yet they function just fine.

'Our' velocity factor theory ????

Ah, now I understand something.  Jared thinks that when we talk
about velocity factor along wires, we are presenting some
oddball, probably wrong, hypothesis made up by ourselves.  He
apparently doesn't seem to realise that we're just describing
well understood and strongly established physics and electrical
engineering.

This is no doubt the reason Jared ignores us whenever we point
out the errors in his naive calculations, and instead continues to
plug his wrong ideas (it seems mainly to newbies because he
realises by now that it won't wash with the rest of us).

The fact is, calculations based on known physics give the right
answers for coil resonance - they match careful measurements.
Jared's silly arithmetic gives the wrong answers - they don't
match what is measured.

Part of the problem is: Jared won't do the measurement that
will show he is wrong.  We've suggested many times that he
actually measures the resonant frequency of a solenoid!
That's all it will take to show that known physics is right,
and that Jared is wrong.  The difference is large, up to a factor
of two in typical Tesla secondary solenoids, so it's hard to miss!

The argument put forward as confirming evidence for his faulty
resonance calculations appears to be based ultimately on the
observed fact that his current and voltage nodes are in the
expected places.

There are two points to make about this.   First, he doesn't
appear to have measured any resonant frequencies, he seems to be
happily assuming that because the nodes are where they are supposed
to be, the frequencies must also be what they are supposed to be.
This isn't the case.   Second, winding two bipolar halves with
equal wire length but different inductance in each, does not
guarantee that the voltage node will be displaced from the junction
of the two coils by a significant amount.  End capacitance of each
coil will tend to draw the voltage node and current anti-node
towards the junction, regardless of the inductance imbalance, and
it is doubtful if he will have noticed the remaining offset.

If Jared would just take the trouble to measure the resonant
frequency of one coil, just a simple solenoid, and compare that
with the coil's wirelength, he will see that it is very different
from his predictions.  He will instead find the wire velocity to
be within a couple of percent of the velocity factor curves for
the first three resonant modes given in

 http://www.abelian.demon.co.uk/tmp/ph1.gif
 http://www.abelian.demon.co.uk/tmp/ph3.gif
 http://www.abelian.demon.co.uk/tmp/ph5.gif

All this is old ground, we have covered this stuff at great
length until we're all fed up of it, but it doesn't seem to get
through.

It boils down to this: (repeating myself now...) if you wind and
measure a coil, it won't resonate at the frequency you would expect
it to resonate at if you assume that signals traverse the wire at a
speed given by the universal constant 'c'.

Instead, it will resonate at a frequency within a very few percent
of a prediction based on the well understood and fairly basic physics
that we've been trying to teach Jared.

Of course, most of us have already given up trying to flog this
very dead horse.  We know from experience that Jared doesn't take
in what is explained to him.  But from time to time we have to speak
up so that newbies are less likely to be misled.
--
Paul Nicholson
Manchester, UK.
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