What is the number of cycles of a sine wave that are completed in 1 second known as?

The number of cycles of a sine wave that are completed in one second is termed frequency. It measures how often the wave oscillates within that time frame, providing a quantitative description of the wave's periodic behavior. Frequency is typically expressed in hertz (Hz), where one hertz is defined as one cycle per second.

Understanding frequency is crucial in various applications, including audio and radio transmissions, because it directly influences pitch and wave properties. For instance, different frequencies correspond to different musical notes, and radio stations broadcast at specific frequencies to ensure clear signal transmission.

In contrast, amplitude refers to the maximum extent of the wave's displacement from its rest position, wavelength indicates the distance between two successive points of equivalent phase on the wave (such as crest to crest), and phase describes the position of a point in time on a waveform cycle. Each of these elements relates to wave properties but does not directly quantify the rate of oscillation as frequency does.