What is the relationship between wavelength and frequency?
Sometimes electromagnetic radiation is described using its frequency rather than its wavelength. These two characteristics are closely related. If we could watch a wave of electromagnetic radiation pass, the wavelength would be the distance between two adjacent wave crests, the frequency would be the number of wave peaks that passed in a given time. Since electromagnetic radiation travels at a constant speed in a constant environment, radiation with a longer wavelength would have fewer waves passing in a given time (lower frequency) and radiation with a shorter wavelength would have more waves passing in a given time (higher frequency). When wavelength increases, frequency decreases and visa versa.