What force causes a 3-pole motor to spin one way and not the other?

If you look atHow Electric Motors Work场磁铁,你会看到and the rotor magnet attract and repel one another at different points in the cycle.

Thecommutatoris in charge of flipping the rotor's magnetic field. The direction of rotation therefore depends on which way the current is flowing through the rotor. If the motor is driven by abatteryand you flip the polarity of the battery, the direction will reverse.

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