How can the direction of a fan motor be reversed?

The direction of a fan motor can be reversed by reversing the polarity of the power supply to the motor. This is particularly applicable to DC motors, where the direction of current flow determines the rotation direction. By switching the connections of the positive and negative terminals, you effectively change the direction of the magnetic field generated within the motor, leading to a reversal in the rotation direction.

This principle does not apply to options that suggest changing voltage levels or altering fan blade structure since these methods do not influence the direction of the motor's rotation. Additionally, swapping motor windings is not a standard practice for reversing the direction; it would require modifications to the physical wiring or construction of the motor itself, which is not practical for simple operation. Thus, reversing the polarity of the power supply provides a straightforward and effective means to change the motor's direction.