Question

Explain Laplace correction of velocity of sound​

Answer 1

Answer:

Laplace correction gives correction to the speed of sound in the gas. The formula for the speed of sound in the gaseous medium was estimated by Newton, he assumed that the propagation of sound waves in air or gas is under isothermal condition. This assumption was found contradictory, the speed of sound in the air was found to be 280m/s which wasn’t accurate. Thus, Laplace came up with a correction to it which was evident theoretically as well as practically. Thus it is well known as a Laplace correction to Newton’s Formula.

Answer 2

Explanation:

Laplace's assumption of isothermal conditions to prevail when sound travels through air, Newton has applied Boyle's law to pressure changes and volume. In a region of compression, there is nominal increase in temperature and in a region of rarefaction, there is marginal decrease in temperature. These changes in pressure occur rapidly and air is a poor conductor of heat thus, equalization of temperature among the different regions was improbable, according to Laplace. He was of the view that the changes in temperature occur under adiabatic conditions, i.e., no heat enters into the gas from outside or leaves it from inside. The heat developed in the compressed layers remains fully confined to these layers and has no time to get dissipated into the entire body of the gas. Similarly, the cold caused in the rarefied layers cannot be compensated, by flow of heat inside it from other layers.