Propagation of Sound Waves

Since sound waves are longitudinal, their propagation through air always involves the formation of compressions and rarefactions exactly as described earlier for a vibrating tuning fork. This section works out the theoretical speed of sound in air in three stages: first following Newton's own historical (but ultimately flawed) reasoning that the process is isothermal, then presenting Laplace's later correction recognising that the process is actually adiabatic, and finally cataloguing the practical factors -- pressure, temperature, density, humidity, and wi …