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Bill[_4_] Bill[_4_] is offline
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First recorded activity by BoatBanter: Oct 2007
Posts: 78
Default NORDHAVN Rewrites Physics Textbooks


"Richard Casady" wrote in message
...


Unfortunately your calculation is more or less meaningless, and I can
only hope you had a good calculator and didn't waste a lot of time on
it. Since the earth and its magnetic field rotate together, the
maximum velocity relative to the magnetic field, is precisely zero. So
zero voltage is what you get that way.


Casady



So you never heard of Faraday's Paradox?

http://en.wikipedia.org/wiki/Faraday_paradox

"The experiment proceeds in three steps. First, the magnet is held to
prevent it from rotating, while the disc is spun on its axis. The result is
that the galvanometer registers a direct current. The apparatus therefore
acts as a generator, variously called the Faraday generator, the Faraday
disc, or the homopolar (or unipolar) generator.

In the second step, the disc is held stationary while the magnet is spun on
its axis. The result is that the galvanometer registers no current.

In the third step, the disc and magnet are spun together. The galvanometer
registers a current, as it did in step 1."



Another reference:

http://www.physics.brown.edu/physics...emo/5k1080.htm

a.. "Rotating disc; rotating magnet
As stated above, the motion of the magnetic disc is immaterial. Therefore,
as long as the conducting disc is rotating, the galvanometer will indicate a
current as in the first case. "