People may be having a little trouble understanding frequency.
The frequency of standard U.S. power transmission infrastructure is at 60 Hertz (cycles per second).
In a generator, there is a stater and a rotor. Coils move past magnets. In AC (alternating current), the magnets are arranged around a circle north, south, north, south, etc. The coils pass the magnets and at every pass-by, the polarity of the current reverses, so it's positive, negative, positive, negative, etc. If it were in D.C. (Direct Current), you would have a sine wave that only filled the space above the X-axis. Otherwise, in AC, you have a nice sine wave you can measure in an oscilloscope.
Faster spinning generators create a higher frequency wave you can see with an oscilloscope. You can transform that frequency just like how an old radio dial works once the current leaves the generator and has its characteristic sine wave. As you transform the volts, so does the frequency. That's why many scientists, Tesla included considers it volt/frequency, which can be regarded as very much the same thing, but there is a difference to note that I have explained.
It's a simple principle of radio, like in an AM bar antenna -- frequency transformation. Ever had an old crystal radio set?
In a bar antenna, it's a coil of wire wound around a magnet. The magnet doesn't have to be there, but otherwise you'd need a very long coil that had to fill a building. Otherwise the magnet increases the resonance of the electromagnetic waves, and increases the frequency thusly, so you can tune into a spectrum of radio frequency. That principle of tuning the dial is that of a variable transformer.
At one end, you have higher volts and higher frequency thusly. At the other end, you have lower volts and frequency, when the power comes from a generator.
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A device like a dremel can increase the frequency (cycles per second) even higher. But since the coils in the stator are so narrow, the distance between the electromagnetic poles (north / south) in the electromagnetic fields generated are so close that they tend to cancel each other, and so the volts are way lowered.
A fat coil where the north and south poles have a good separation don't cancel each other, and the volts are preserved, and not traded off for speed.
In such a design, the volts will measure less, but the frequency (speed) will increase. A motor can transform the frequency from a generator also. The concept of transformation is fairly general, working one coil with another coil to change volts / frequency is where I'm focusing on in this article.
Since some people have had a hard time understanding "frequency transformation," I hope that helps . . .
Now, onto Starship Physics!
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