All,

I would appreciate it if the contributors to such off-topic and radically
changed treads would change the subject title.

--
- Cortlandt Wilson
  Cortlandt Software

John D. Alleyn-Day <[log in to unmask]> wrote in article
<[log in to unmask]>...
| Wirt Atmar <[log in to unmask]> wrote:
|
| .......<snip>
|
| >And Ted Ashton is also correct. As the frequency of an AC current is
| >increased, it has a increased tendency to flow more and more on the
surface
| >of a wire (not necessarily a person). The phenomenon is called the "skin
| >effect" and it is due to the fact that there is a "freer" gas of
electrons
| >near the surface of a wire (or any metal) than there is near its center.
|
| No, the skin effect is a phenomenon that is forecast by Maxwell's
equations
| and predates any kind of electron theory.  It is caused by an interaction
| between the magnetic and electric fields that "pushes" the current to the
| outside of the conductor.  The skin depth is inversely proportional to
the
| square root of magnetic permeability (as well as conductivity and
| frequency) and that leads to the interesting fact that it is significant
at
| much lower frequencies in magnetic materials such as iron than in
| non-magnetic materials such as copper.
|
| John D. Alleyn-Day
| Alleyn-Day International
| 408-286-6421   408-286-6474 (Fax)
| [log in to unmask]       http://www.Alleyn-Day.com
|