- A. General Materials & Mathematics
- B. Statics
- C. Kinematics & Dynamics
- D. Rotational Mechanics
- E. Gravitation & Astronomy
- F. Fluid Mechanics
- G. Vibrations & Mechanical Waves
- H. Sound
- I. Thermodynamics
- J. Electrostatics & Magnetostatics
- K. Electromagnetic Principles
- L. Geometrical Optics
- M. Wave Optics
- N. Spectra & Color
- O. Vision
- P. Modern Physics
H6-04. Helium Voice
To demonstrate the rise in frequency of vocal formants due to the increase in the speed of sound in a light gas.
Tank of helium with regulator and pressure gauges.
Take a couple of big breaths of air first to get plenty of oxygen, then breath out completely before inhaling the helium.
Snort a lungfull of helium and talk and sing normally. Your voice takes on a squeaky "Donald Duck" character due to the increase in frequency of your vocal formants.