Magnetic field in a rotating magnet

AI Thread Summary
The discussion explores the relationship between magnetic fields and rotating magnets, emphasizing that magnetic fields arise from moving electric charges. It notes that the velocity of electrons in copper is significantly lower than that of a spinning CD, suggesting that if electrons flowed around the CD, their speed would increase, potentially strengthening the magnetic field. A setup involving a CD with copper wire wound around it and connected to a power supply produces a measurable magnetic effect, as indicated by the movement of a screwdriver with a magnetic tip. Questions arise about the behavior of protons in this context and whether a statically charged spinning object can generate a magnetic field. The thread concludes with an interest in experimenting with a high-voltage source to further investigate electron dynamics in this scenario.
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the theory

magnetic field is produced by moving electric charges
the field is proportional to the quantity and velocity of those charges

the velocity of electrons is about 1mm/s at 15A/mm~2 in copper

the velocity of a cd spinning is about 1000RPM 6m/s 6000 times more the the speed of the electrons

so if the electrons where to flow around a cd that is spinning at 6m/s the electrons should move at 6.001m/s and the field 6000 times stronger

the setup

a cd with copper wire wound around it (20windings) with two contacts (see picture) that are connected to a pc power supply at 12V results in about 2A.

the screwdriver has a magnetic tip and rotates about 45deg when current is flowing throw the copper coil wile not spinning.

the result
the screwdriver moves exactly the same amount??!

anyone has an idea? electron velocity not in the mm/s range?
 

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What happens to the protons when you spin the entire disc?
 
the protons will create the opposite magnetic field and cancel out the field generated by the electrons. thank you!

so a staticly charged spinning object should generate a magnetic field...

i got a 7kV source (ignition coil from my car). let see if i can figure out in how many electrons that translates too in CD...
 
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