Question

What is wavelength used for?

Answer 1

1. A waveform signal's wavelength is defined as the separation between two successive crests or troughs traveling through space or via a wire.
2. Typically, a wave's wavelength is expressed in $\mathrm{metres}\left(\mathrm{m}\right)$, $\mathrm{centimetres}\left(\mathrm{cm}\right)$, or $\mathrm{millimetres}\left(\mathrm{mm}\right)$.
3. The relationship between frequency and wavelength is inverse. The wavelength of a signal decreases with increasing frequency.
4. The main use of wavelength is to identify waves in the electromagnetic spectrum from the longest wavelength to the shortest.

In the diagram, $\lambda$ is representing the wavelength.