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Newton’s formula for the velocity of sound in gases Newton was of the opinion that longitudinal waves travel in a gaseous medium, the changes taking place in the medium are isothermal in nature. Thus, according to Newton, the temperature of the gaseous medium remains constant, when sound travels through it. At the regions of compression, where the heat is produced, the heat is conducted away to the surrounding medium and at the regions of rarefaction, where cooling is produced, the heat is conducted in form the surrounding medium. Velocity of sound in gases Thus, in the equation V= √(B/ρ) ….(1) B represents isothermal bulk modulus of the gas whose value is equal to the initial pressure (p) of the gas. Therefore, according to Newton, the speed of sound in gasses is given by: V= √(P/ρ) ….(2) Let us use the equation (2) to estimate the value of the speed of sound in air at N.T.P. We know that for air at N.T.P. P= 76 cm of mercury column = 76×13..6×980 dynes/cm 2  = 1.01 ×...