Frequency class 8 refers to the concept of frequency taught in 8th-grade science classes. Frequency is a measure of how many waves pass a point in a certain amount of time. It is defined as the number of oscillations an object takes per second and is measured in Hertz (Hz), which is the SI unit of frequency. The frequency of a sound wave is the number of vibrations made by a particle of the medium in one second. In summary, frequency class 8 refers to the basic understanding of frequency as taught in 8th-grade science classes.