An AC signal is typically shown as a _____ wave.

An AC signal is typically shown as a sine wave because it represents the smooth, periodic oscillation of alternating current over time. The sine wave shape reflects the continuous and uniform nature of AC voltage, where the signal alternates between positive and negative values smoothly, with a consistent frequency. This waveform is fundamental in electrical engineering and telecommunications, as it accurately depicts how AC power operates in real-world applications, including power supplies and audio signals. Understanding this form of representation is crucial for analyzing and working with AC circuits, as it influences how devices receive and utilize electrical energy.