Re: looking for inductance formulae that include resistance effects

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

Original poster: "Jan Wagner" <jwagner-at-cc.hut.fi> 


On Sat, 2 Oct 2004, Tesla list wrote:
>Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> I'm looking for 
>"handbook" type formulas (that I can put into a spreadsheet
>fairly easily) that can calculate not only the inductance of a flat or
>helical coil, but also the resistive loss (which, of course, will vary with
>frequency).  Preferably not something that uses a big table of constants
>(like Medhurst for capacitance) and not that requires running a numerical
>integration (like INCA).

If you know the tube material, dimensions, and freq, you could get a good 
estimate of the AC resistance by using the formula for skin depth. As 
derived in, for example:
http://www.physics.uq.edu.au/people/ficek/ph348/sols/sol12/node2.html#SECTION00011000000000000000
(and asserting that the assumptions made in the derivation are valid in 
your case too, e.g. diameter of the conductor is large compared to the skin 
depth, etc)

Is this what you were looking for? Or a more "precise" formula?

cheers,
  - Jan

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