Summarizing Sound Interference and Resonance

Summary

• Sound interference and resonance have the same properties as defined for all waves.
• In air columns, the lowest-frequency resonance is called the fundamental, whereas all higher resonant frequencies are called overtones. Collectively, they are called harmonics.
• The resonant frequencies of a tube closed at one end are:

  \({f}_{n}=n\cfrac{{v}_{w}}{4L}\text{,}n=1, 3, 5\text{.}\text{.}\text{.,}\)

  \({f}_{1}\) is the fundamental and \(L\) is the length of the tube.
• The resonant frequencies of a tube open at both ends are:

  \({f}_{n}=n\cfrac{{v}_{w}}{2L}\text{,}n=1, 2, 3\text{.}\text{.}\text{.}\)

Glossary

antinode

point of maximum displacement

node

point of zero displacement

fundamental

the lowest-frequency resonance

overtones

all resonant frequencies higher than the fundamental

harmonics

the term used to refer collectively to the fundamental and its overtones