Is this good for educators?

Yes — this version of "Helmholtz Resonator for a resonant room" is framed for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs.

Do I need to install anything?

No. It runs in any modern browser, free, with no account required.

For Educators · Helmholtz Resonator

Helmholtz Resonator for a resonant room

Built for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs. Simulate a resonant room live below — adjust the inputs and watch it respond, right in your browser.

Helmholtz ResonatorLive

the resonance of a bottle

Controls

Presets

Cavity volume (cm³)

Neck diameter (cm)

Neck length (cm)

Blow across a bottle and it sings at its Helmholtz frequency. The plug of air in the neck acts as a mass and the air in the cavity as a spring, giving f = (c/2π)√(A/VL). Bigger cavities and longer necks lower the pitch — the principle behind bass ports, mufflers, and ocarinas.

▶ Run in Python

Data Inspector

Resonant frequency167 Hz

Wavelength2.05 m

Cavity500 cm³

Governing equation

f = \frac{c}{2 π} \frac{A}{V L _{eff}} = \frac{343}{2 π} \frac{3.14 e - 4}{5.00 e - 4 \cdot 0.067} = 167 Hz

Reading this result: This cavity sings near 167 Hz — a 2.05 m wavelength. Enlarge the cavity or lengthen the neck and the pitch drops, because both add to the mass-on-a-spring that sets the tone.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

or unlock everything with Pro →

Also for:Students Researchers Engineers Hobbyists & Makers K-12 Students First Responders General version →

More with Helmholtz Resonator

Helmholtz Resonator for a guitar string Helmholtz Resonator for a concert hall Helmholtz Resonator for a speaker Helmholtz Resonator for a drum head Helmholtz Resonator for a sound wave Helmholtz Resonator for a piano note Helmholtz Resonator for a noise barrier Helmholtz Resonator for a whisper gallery

Frequently asked questions

Is this good for educators?: Yes — this version of "Helmholtz Resonator for a resonant room" is framed for educators teaching it to a class. Drop a live demo into a lecture or assign it as a shareable link — no lab installs.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.