ABSTRACT
If we imagine the piston in Fig 1 to be suddenly moved forward a short distance, the air immediately adjacent to its face will be compressed. This compressed region will in turn affect the region next to it and the disturbance will pass down the tube compressing subsequent sections of air in turn. The speed at which the disturbance will pass down the tube will depend upon the density of the air and its bulk modulus. For air at normal temperature the disturbance will travel at approximately 340m/sec (1120ft/sec).
