What type of current flows in an AC circuit?

In an AC circuit, the type of current that flows is called Alternating Current. This type of current is characterized by its periodic change in direction and magnitude, typically represented as a sinusoidal wave. In an alternating current system, the current reverses its polarity at regular intervals, which distinguishes it from direct current (DC) that flows in a single direction.

Alternating current is widely used for power distribution because it can be easily transformed to different voltage levels, making it more efficient for long-distance transmission. This efficiency is a key reason why AC is the predominant form of electrical power used in homes and industries. Additionally, many electrical devices are designed to operate on AC due to its properties.

Contrarily, direct current flows consistently in one direction and lacks the periodic reversal characteristic of alternating current. Static current generally refers to the presence of charge at rest rather than the movement of charge, which makes it unrelated to the flow in typical current circuits. Complex current typically refers to a combination of AC and DC components in certain contexts, but it does not specifically define the current that primarily flows in standard AC circuits. Therefore, Alternating Current is the correct and most appropriate term for what flows in an AC circuit.