Some people consider an education important, or have had jobs that involve some of the stuff outlined here, and actually have knowledge of their own to draw from without having to look up every little detail.
It helps when you go to apply concepts to understand them, and it sure beats having nothing interesting to say and bitterly lashing out at those who did.
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Anyway, yeah, the axle concept is the general idea. Or you could get an allen wrench or anything L shaped and screw it into the chuck and turn it by hand. That's actually related to the reason that AC current is shaped like a wave form. If you take a circular motion, and you plot it over time, you get a wave (oscillating voltages being measured as they go through a fixed point).