What characterizes alternating current (AC)?

Alternating current (AC) is characterized by its ability to constantly change both magnitude and direction. This unique property distinguishes AC from direct current (DC), which flows in a single direction. The alternating nature of AC is reflected in the way the voltage fluctuates over time, often in a sine wave pattern. This alternating flow of electric charge is vital in many applications, such as in residential and industrial power systems, where it is more efficient for transmitting electricity over long distances.

Additionally, the alternating current not only enables the switching of power to different devices but also supports the operation of transformers and various electrical machines, which utilize the changing magnetic fields generated by this current. This capability to generate and respond to magnetic fields is essential in the functioning of motors and generators, making AC a crucial aspect of electrical power systems.