In an alternating current (AC) circuit, what happens to the voltage over time?

In an alternating current (AC) circuit, voltage fluctuates periodically. This behavior is intrinsic to AC, which is designed to change direction and magnitude over time in a sinusoidal pattern. This oscillation means that the voltage is not static; instead, it varies continuously as the current flows in one direction and then reverses.

The periodic nature of this fluctuation is typically characterized by its frequency, which defines how many cycles occur in a second, and its amplitude, which indicates the peak voltage. The voltage in an AC circuit reaches positive and negative peak values, demonstrating the transition from positive to negative at regular intervals. This property allows AC to be effectively used in power distribution and is why it is prevalent in residential and commercial electrical systems.

Understanding the periodic fluctuation in voltage is crucial for various applications, including the operation of electrical devices designed specifically for AC power.