The distance between two adjacent particles of the same phase along the propagation direction of the wave is called the "wavelength". It refers to the distance between any two particles with a phase difference of 2π in the wave medium. For example, in a longitudinal wave, the distance between the centers of two adjacent sparse parts or the distance between the centers of two adjacent dense parts is also equal to the wavelength. In a transverse wave, the distance between two troughs or the distance between two peaks is also equal to the wavelength. From the definition of wave velocity and wavelength, we can know that: within one cycle of particle vibration, the distance the vibration state propagates is exactly one wavelength, so λ=v/f, or λ=vT. From the above formula, we can see that waves of the same frequency have different wave velocities in different media, and therefore different wavelengths. In the formula, λ represents the wavelength. Wavelength, wave velocity and wave source vibration frequency are called the three elements of the wave.

Wavelength of sound: W = V/F

here

W = wavelength

F = wave frequency

V = wave speed