Links to related material and teachers' resources  
Pitch, loudness and timbre
Frequency and pitch. Amplitude and loudness. Timbre examples, with envelope and spectrum. 
Sound pressure and density; Transverse vs longitudinal waves
Transverse vs longitudinal waves. y(x') in a longitudinal wave. Density variations. A travelling longitudinal wave. Variations in pressure give rise to accelerations.
Sound transmission through air. Bell jar experiment. If sound diffracts, why doesn't light?
Speed of sound
Time-of-flight measurements of the speed of sound. Clap-echo measurement. Clap-board (image vs sound) measurement. Experiments using two microphones and a long cable.
Adiabatic expansion and compression
The relationship between pressure, volume and temperature for a rapid (adiabatic) change in volume of a gas.
Displacement, compression and pressure. Newton's second law and acceleration. The wave equation for sound. Speed of sound. Acoustic impedance.

Acoustic compliance, inertance and impedance
Acoustically compact regions in which inertia dominates (inertance) or compressibility dominates (compliance). The characteristic impedance of a duct.

The Mexican Wave
The mexican wave (or stadium wave) is an example of a travelling wave.

Downloads (thumbnails at 50% of size of animation)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)
Download (.zip)