What is the difference between alternating current (AC) and direct current (DC)?

The distinction between alternating current (AC) and direct current (DC) is crucial in understanding their applications and behaviors in electrical systems. The correct answer highlights that AC is typically used for high-voltage applications, while DC is often applied in low-voltage scenarios.

AC is characterized by its ability to change direction periodically, making it suitable for transmitting electricity over long distances. When AC is generated, it can easily be transformed to higher voltages through transformers, reducing energy loss during transmission. This characteristic of AC allows it to be more efficient for high-voltage applications, such as power grids and large-scale electrical distribution systems.

On the other hand, DC provides a constant flow of electricity in one direction, which is beneficial for low-voltage applications such as batteries, electronic devices, and circuits where a stable voltage is required.

Understanding this difference in application helps to clarify the roles of AC and DC in modern technology and reinforces why AC is predominantly utilized for high-voltage power transmission, while DC serves effectively in low-voltage contexts.