RE: New Inductance Formula

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Inductance is defined as the flux linkages divided by the current causing
the flux or

   L = A/I

Refer to page 538 the Electromagnetics Problem Solver by Dr. M. Fogiel,
1983, Research and Education Association.

John Couture

----------------------------


-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Sunday, April 28, 2002 9:14 AM
To: tesla-at-pupman-dot-com
Subject: RE: New Inductance Formula


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

Hi Ed,

>Wheeler's formulae (there are several) are usually known as Wheeler's
approximations, and were developed during "slide rule days" as a convenient
and simple tool for radio engineers, who seldom need an accuracy of as great
as 1%.

Wheeler's formulas have served us well for quite a while.  I'm not disputing
that nor am I disrespectful of his contribution.

>Quite recently a guy named Lundin (?) worked out fairly simple expressions
giving an accuracy of better than a part in 300,000.

I'd like to see that formula.  If you or anyone else knows where to find it
please post it to the list.

>By the way, I believe the dimension of inductance is indeed length,
(centimeters in the old cgs system) though don't have time to look that up
right now.

The dimensions of inductance in the MKS system are kg*m^2/coul^2.  In the SI
system it is kg*m^2/s^2*A^2.  In the cgs system it is sec^2/cm.

Dave