Why don’t devices like fans reverse their direction despite using alternating current (AC), which changes direction?

Question

Why don’t devices like fans reverse their direction despite using alternating current (AC), which changes direction?

In: Physics

Answer 1

Single-phase AC motors are made with the knowledge that current reverses. They coast while the current is going down and reversing, bringing an opposing pole into position for the rising reversal to continue to rotate the mechanism in the same direction. That’s why big ones sometimes require a capacitor to kick them started and build up the momentum needed.