How real electric motors work

John Storey


8. The infamous "ball bearing" motor

This motor is nothing more than a shaft supported by two ball bearings. Current is fed to the outside of one bearing, runs through the shaft, and out the other bearing. It sometimes needs a little kick to get it started, but once turning will run equally well in either direction.

• Perfect conversation-starter at parties
• Creates confusion amongst engineers

• Completely useless
• Requires staggeringly high currents to make it turn

This motor has no windings, brushes, magnets, and cannot possibly work. Except that it does. Click here for an explanation.




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