What is defined as the number of complete waves passing a given point in a second?

The definition of the number of complete waves passing a given point in a second is indeed frequency. In wave mechanics, frequency is a fundamental property that quantifies how often a repetitive event occurs within a specific timeframe. It is typically measured in hertz (Hz), where one hertz corresponds to one complete wave cycle passing a point in one second.

Understanding frequency is crucial in various applications, including ultrasonic testing, where the frequency of the sound waves can affect the resolution and penetration of the waves into the material being tested. Higher frequencies generally provide better resolution, while lower frequencies can penetrate thicker materials.

The other terms relate to various aspects of waves but do not define the rate of wave cycles. Amplitude refers to the height of the wave from its mean position, indicating energy rather than the number of cycles. Wave velocity is the speed at which the wave travels through a medium, while wavelength is the distance between successive peaks of the wave. Each of these characteristics plays a significant role in the overall behavior of waves but does not describe the frequency of wave occurrences.