How To Calculate The Wavelength Of Sound

The procedure to calculate the wavelength of sound (that is, the distance a sound waveform travels between its peaks) is dependent on the pitch of the sound and the medium the sound travels through. In general, sound travels faster through a solid than a liquid, and sound travels faster through a liquid than a gas. A sound wavelength calculation requires that you know the speed of sound through the specific medium and the pitch of the sound. Once these two variables are known it is just a question of dividing the speed of sound by the pitch to obtain the wavelength of sound.

Step 1

Determine the speed of sound for the specific medium the sound travels through. Look up in a speed of sound table the speed of sound for the medium. Look in a speed of sound liquid table if the sound is traveling through a liquid such as salt water or fresh water. Look in a speed of sound gas table if the sound is traveling through a gas such as air or helium. Look in a speed of sound solid table if the sound is traveling through a material such as cork, concrete or wood.

Step 2

Determine the pitch of the sound. Remember that the frequency, or pitch of a sound, is the number of times a sound pattern repeats itself per second, measured in cycles per second. Use a sound frequency meter to measure the pitch or estimate the pitch. Consider that the human ear can hear sounds in the range of 20 cycles per second (low bass-like notes) to 20,000 cycles per second (high flute-like notes).

Step 3

Calculate the wavelength of the sound. Divide the speed of sound determined in Step one by the pitch of sound determined in Step 2.