How Do You Calculate Current from a Faraday Disc?

AI Thread Summary
Calculating current from a Faraday disc involves considering factors like back electromotive force (emf) and the specific motor's torque. While voltage calculations are more straightforward, determining current requires additional complexity. Using a flat coil instead of a solid disk can enhance efficiency if the coil's magnetic field aligns with the stator magnets. Resources like the linked article provide further insights into the topic. Understanding these principles is crucial for effective generator design and performance.
charlie r
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Hi,

How do you calculate the current from a faraday disc? I have found calculations for the voltage, but what about the current?
I think it is a bit more complicated due to back emf, but if you know what motor you are using (the torque it can generate), then can you work it out?
Thanks for any help,

Charlie
 
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Thanks Drakkith, great link.
It seems that this isn't as simple as i first hoped it was!

Charlie
 
If you use a flat coil instead of solid disk and coil is wind in such direction, that its magnetic field adds to the field of stator magnets, the generator will be more efficient.
 
Thread 'Motional EMF in Faraday disc, co-rotating magnet axial mean flux'
So here is the motional EMF formula. Now I understand the standard Faraday paradox that an axis symmetric field source (like a speaker motor ring magnet) has a magnetic field that is frame invariant under rotation around axis of symmetry. The field is static whether you rotate the magnet or not. So far so good. What puzzles me is this , there is a term average magnetic flux or "azimuthal mean" , this term describes the average magnetic field through the area swept by the rotating Faraday...
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.
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