Homopolar Generator Setup & Effect of Magnetized Conductivity

AI Thread Summary
The discussion centers on the setup of a homopolar generator, which typically consists of a stationary magnet and a rotating conducting plate. There is speculation about the effects of spinning the magnet instead of the plate, questioning whether current would still be induced under these conditions. The conversation highlights the importance of understanding how magnetism and conductivity interact, particularly in permanent magnets. A suggestion is made to experiment with a magnetized iron nail in a circuit to explore its conductive properties. Overall, the relationship between magnetization and conductivity remains a key point of curiosity in the discussion.
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The basic set up for a homopolar generator has a stationary magnet and a rotating conducting plate with contacts at the center and rim of the plate.
I would think that even if magnet were spinning along the same axis, the magnetic field would not materially change and so the resulting current would be the same.

What if, instead of a separate plate, the magnet were spinning and had contacts attached in a similar way? Would there still be a current induced?

To clarify, the poles of the magnet are aligned with the axis of rotation. I don't really have an understanding of how conductivity would change when an object is magnetized. This may be the real issue.
 
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Welcome to PF;
You want to spin the magnet, keeping the metal stationary.
You can figure out what would happen by the Lorentz Force Law.
http://en.wikipedia.org/wiki/Homopolar_generator#Physics

Note: magnetics is generally frame-dependent, so I'd expect something different to happen.
 
Thanks for the response. I think I understand the physical concepts but I'm still curious about how conductivity works in permanent magnets, and if a conducting magnet is useful as either a conductor or magnet.
 
Well, to find out how permanent magnets work as conductors, get an iron nail, put it into a circuit with a variable voltage source, ammeter and voltmeter, collect and plot V vs I ... repeat for the same nail magnetized to different amounts.

I used to have a model steam-engine with magnetic wheels - both magnetic and conductive properties were useful.
 
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