What is the difference between single-phase and three-phase power systems?

The correct answer highlights a fundamental distinction between single-phase and three-phase power systems based on the number of waveforms they utilize. Single-phase power relies on a single alternating current (AC) waveform, which means that power delivery fluctuates between positive and negative cycles. This system is commonly used in residential applications and smaller loads due to its simplicity and cost-effectiveness.

In contrast, three-phase power consists of three separate waveforms that are offset by 120 degrees from each other. This configuration allows for a more constant and balanced power supply, making it highly efficient for transmitting large amounts of electricity over long distances. The continuous nature of the power supply in a three-phase system results in smoother operation of motors and other heavy electrical equipment, which improves overall performance and reduces wear.

Understanding the difference in waveforms is essential for those working with electrical systems, as it directly influences the choice of system type depending on the application, load requirements, and efficiency needs.