Frequency is a measure of how often something happens within a certain period of time. In the context of light waves, it refers to the number of oscillations or cycles that occur per unit of time, typically per second. The symbol for frequency is not the letter "v"; it is the Greek letter "nu" (which looks like 'v' but is not the same). When we talk about the frequency of light waves, we are referring to the number of complete light wave cycles that pass a given point in one second. The unit of frequency is the Hertz (denoted by the symbol Hz), named after the German physicist Heinrich Hertz. One Hertz means that there is one cycle per second. read more >>

It is NOT the letter v, it is the Greek letter nu. It stands for the frequency of the light wave. Frequency is defined as the number of wave cycles passing a fixed reference point in one second. When studying light, the unit for frequency is called the Hertz (its symbol is Hz).read more >>