Wf-2 Helmholtz Resonators
Aim
To demonstrate a Helmholtz resonator, i.e. an acoustic device that exhibits mechanical resonance with small damping.
Apparatus
- Helmholtz Resonators
- Stand
- Tuning Fork or Loudspeaker
- Amplifier
- C.R.O.
Helmholtz Resonator Diagram.
Description
A Helmholtz resonator consists of a volume V fitted with a short open neck N. The air in the neck functions like a piston and the air in the cavity as a spring.
The frequency f, of the free vibrations of the air in the neck is given by
Where S is the area of the neck
L is the length of the neck
V is the volume of the cavity