Pure tone sound waves are sinusoidal oscillations of the density of air. our model of waves on an elastic string (beads and massive strings) suggests that waves of moving matter depend on a restoring force (like a tension) and inertia (like a mass), we expect that the speed of sound in air should depend on the air pressure, p (normally about 100 kpa) and the density of the air, rho (normally about 1 kg/m³ ). Using dimensional analysis, propose an equation for the speed of sound in air using only the parameters P and e.