Oscillations and Waves > Instruments > Air Columns | DCS# 3D30.40 |
Helmholtz resonators | 202-06-C |
function generator | 202-08-G |
speaker |
202-07 |
Sweep through the frequencies of the function generator and listen for the resonant frequency of the spherical cavity. Use a microphone and oscilloscope to show the change in amplitude.
Helmholtz resonators were an early version of the spectrum analyzer: to identify frequency components in a given note, place one end of the resonator of the frequency of interest to your ear and listen for that frequency in the note.
Tom Greenslade's early physics apparatus pages:
http://physics.kenyon.edu/EarlyApparatus/Acoustics/Helmholtz/Helmholtz.html