Re: [Phys-l] Is skin efffect a factor?

[John Denker <jsd@av8n.com>]

On 06/05/2009 09:55 AM, Bernard Cleyet wrote:
> > > A typical back EMF demo is to drop a magnet on to a conducting
> > > plate.  One inch thick Cu cooled w/ LN2 is usual.  I wonder;  will
> > > 1/2 inch thick work as well and, if so, because of skin effect?
> >
> > Is this not the world's easiest dimensional analysis (i.e.
> > dimensional scaling) exercise?
> >
> > If not, please explain where the hangup is.


On 06/05/2009 12:09 PM, chuck britton wrote:

> The hangup for ME is not having a CLUE as to what expression we are  
> scaling!!

Perhaps the skin-depth formula?

One convenient reference:
   http://farside.ph.utexas.edu/teaching/em/lectures/node102.html
specifically equation 1196 therein.

Or Jackson equation 7.77.  Beware Gaussian units, not SI ... although
the choice of units is not going to change the scaling behavior.