RE: New Inductance Formula

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "David Thomson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <dave-at-volantis-dot-org>

Hi Harvey,

>To see why the impedance is not constant we then merely go to the
definition of X(L)= 2 (pi)*f *L.
>So we se that 2 pi L is constant, but the reactance X(L) will then be
proportional to f, the imposed frequency.

I'm missing something.  How does the formula show that inductance is
constant?  As far as I know inductance is not a characteristic of matter or
energy, but matter and energy are influenced by inductance.  A coil's
inductance does change from day to day and I believe someone on this list
was going to run a test to check into this?  I know my coils change
inductance over time.

>Both inductance and capacitance were also expressed in terms of length in
Teslas day, where the CSN always shows inductance recorded in cm, where the
conversion factor is 10^9 cm = 1 henry.

Tesla et al were using the cgs system of units.  It doesn't work for the SI
system.  And in the MKS system, which I am using, the Wheeler equation
results in meters.  But in the MKS system, meters does not equal henries.
Length is merely a distance.

>See H LTranstrom/Turn of the century definitions for cm's of L and C
quantities

That is a very good discourse on cgs.  Thanks.
http://groups.yahoo-dot-com/group/teslafy/message/14

I'll have to study it a while to fully understand how inductance can be
expressed as length.  There must be a one sentence definition of inductance
in terms of length somewhere?  As for expressing capacitance and inductance
in terms of length, to do so is incomplete in itself.  In order to express
inductance as cm there must be a certain amount of other information present
to gather the inductance.  For example, the henry is equal to kg*m^2/coul^2.
Here we know that inductance is a function of mass, area, and distributed
charge.  For inductance to be expressed as length there needs to be other
information present to know a length with reference to what.

Also, since capacitance and inductance are both expressed as cm, how does
one know whether the result of an equation is inductance, capacitance, or
length?  Or are they all the same?

Dave