Question

Explain newton's formula for velocity of sound and its limitation

Answer 1

According to Newton, when sound waves propagate in air, compression and rarefaction are formed. He assumed that the process is very slow and the heat produced during compression is given to surrounding and heat loss during compression is gained from surrounding. So the temperature remains constant and sound waves propagate through an isothermal process.

Laplace provided a correction for Newton’s formula. He assumed that, the process of compression and rarefaction occur very fast and no exchange of heat takes place. Thus, the temperature doesn’t remain constant and the propagation of sound in gas is an adiabatic process.