Best output: fewer big or more small magnets?

[capthook]

Please - I need to order more magnets!

What will give me more output from my separate generator coils?

Fewer large magnets or more small magnets?

Example:  Rotor N/S A/C output with low RPMs can fit (14) 3/4" mags or (20) 1/2" mags.  4 separate generator coils in both setups.  Will a greater number of small magnets give greater output by creating a higher frequency of N/S fluctuations over fewer large magnets? (I can tune the air gap and coil size for either)  Or will the larger/stronger flux field of the larger magnets produce more ouput? (Assuming relatively same coil size as space is limited)

I was thinking of ordering the 1/2" x 1/4" / N45 BrMax: 13300 gauss / Approximate pulling force: 13 lbs

over the 3/4" x 1/4" /Grade N42 / BrMax: 13200 gauss / Approximate pulling force: 18 lbs


What should I get?  And why? 

On a side note: magnet spacing.  I've read preferred magnet spacing is a gap of the same diameter of the magnets 1-1.  1/2" mags = 1/2" spacing.  What if you cram them together nice and tight?  Will this increase ouput with N/S arrangement?

Thank you! .... and thanks!

CH

[capthook]

So - the magnets are moving past the coils.  RPM's is fixed.  How does the magnet size/strength/spacing relate to increasing/maximizing electrical generation??  Which aspect will provide the greatest result?  I'm confused! 

- - - -

Variations of Faraday's Law
The concept of Faraday's Law is that any change in the magnetic environment of a coil of wire will cause a voltage (emf) to be "induced" in the coil. No matter how the change is produced, the voltage will be generated. The change could be produced by changing the magnetic field strength, moving a magnet toward or away from the coil, moving the coil into or out of the magnetic field, rotating the coil relative to the magnet, etc.


At upper left in the illustration, two coils are penetrated by a changing magnetic field. Magnetic flux F is defined by F=BA where B is the magnetic field or average magnetic field and A is the area perpendicular to the magnetic field. Note that for a given rate of change of the flux through the coil, the voltage generated is proportional to the number of turns N which the flux penetrates. This example is relevant to the operation of transformers, where the magnetic flux typically follows an iron core from the primary coil to the secondary coil and generates a secondary voltage proportional to the number of turns in the secondary coil.

Proceeding clockwise, the second example shows the voltage generated when a coil is moved into a magnetic field. This is sometimes called "motional emf", and is proportional to the speed with which the coil is moved into the magnetic field. That speed can be expressed in terms of the rate of change of the area which is in the magnetic field.

The next example is the standard AC generator geometry where a coil of wire is rotated in a magnetic field. The rotation changes the perpendicular area of the coil with respect to the magnetic field and generates a voltage proportional to the instantaneous rate of change of the magnetic flux. For a constant rotational speed, the voltage generated is sinusoidal.

The final example shows that voltage can be generated by moving a magnet toward or away from a coil of wire. With the area constant, the changing magnetic field causes a voltage to the generated. The direction or "sense" of the voltage generated is such that any resulting current produces a magnetic field opposing the change in magnetic field which created it. This is the meaning of the minus sign in Faraday's Law, and it is called Lenz's law.

[capthook]

??

My brain hurts thinking about this - my eyes hurt reading to obtain an answer - and my "clicky on the buy button thingy" is twitching.......

Will someone please enlighten me? 

CH

[konduct]

I would think fewer larger, stronger magnets will give you more inductance / electricity.

[Nastrand2000]

Larger magnets will give higher voltage....But will also cause more drag on the rotor when the magnets pass by the coil.
Jason