[BC] Aluminum and magnetic/electric currents

[Lamar Owen]

On Saturday 04 February 2006 13:21, WFIFeng at aol.com wrote:
> How is that possible, when the magnets around the disc are quite strong?
> Their proximity makes a HUGE difference in the amount of drag the unit
> creates.

[I let 1300 message pile up in BC before cleaning... argh]

By aligning the axis of the disc with the magnetic poles, you can use the 
Earth as the magnet, and forgo the magnet in close proximity.  Yes, this 
means a twirling disc of aluminum (or copper!) with no magnet assembly can 
generate power directly, if its axis is polar aligned.  You do of course need 
to have a source of power to rotate the disc, which will of course be 
magnetically loaded as the electrical load increases.

> If this were so, why don't we have huge generators tapping into Earth's
> fields, now? Sounds like one of those "free energy" scams that have been
> around forever.

The extremely low DC voltage and the extremely low resistance contacts 
required aren't practical to construct, and are anything but efficient.

Found my reference: "Direct Current Machinery" Hempstead S Bull, John Wiley 
and Sons, 5th printing, 1947.  Page 253, subject 'Homopolar Generator'.  
Google for "Faraday Homopolar Generator" for more information.  

Most every watthour meter out there uses a homopolar generator as a brake.

Incidentally, the HPG (as the homopolar generator is commonly abbreviated) is 
the only known true DC electromechanical generator.  No commutator required.  
But no free energy, either.
-- 
Lamar Owen
Director of Information Technology
Pisgah Astronomical Research Institute
1 PARI Drive
Rosman, NC  28772
(828)862-5554
www.pari.edu