This gives it low hysteresis losses when used in AC magnetic circuits.

They also can't rely on a source of power, except for what is available from the (AC) circuit they are connected to.

Reactive power exists in an AC circuit when the current and voltage are not in phase.

The solution principles outlined here also apply to phasor analysis of AC circuits.

Reversal is also encountered in AC circuits, where the peak current will be equal in each direction.

They serve as first approximations for AC circuits.

This is not a safe assumption for AC circuits.

This is the very familiar hum you pick up around unshielded AC circuits.

In AC circuits, Power flow varies as a sine function.

In addition, an oscillating system may be subject to some external force, as when an AC circuit is connected to an outside power source.