Final answer:
Alternating current is current that operates from a voltage source that has a constantly reversing polarity. It is used in most household electrical systems.
Step-by-step explanation:
Alternating current is current that operates from a voltage source that has a constantly reversing polarity. This means that the direction of the current flow changes back and forth over time. AC current is used in most household electrical systems and is represented by a sinusoidal wave. It is different from direct current (DC), which flows in one direction only.
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