Which Is A Better Medium For Sound To Travel- Dry Or Humid Air?

Which Is A Better Medium For Sound To Travel- Dry Or Humid Air?

Sound and light have a faster speed to pass through a different medium, and it is old concepts that we all have been through in schools. You surely need to recall your learning of physics, where the sound rate is learned for different mediums. 

We are here looking at the difference between dry and humid sound travel air and allowing you to hear the better quality sound and faster. To obtain complete information regarding the aspect, consider the reading aspects discussed below.


Dry air or humid air- which is a better medium for sound to travel!

V=√γrtm is the formula of the speed of sound through air. Here r refers to universal gas constant= 8.314 j/mol k. T is absolute temperature, m  is the molecular mass of gas in kg/mol ≈ 28.95 gm/mol for o2  and n2.

Γ shows adiabatic constant for gas= 1.4 air, which mainly includes diatomic o2  and n2.

When following the formula mentioned above that shares moisture content in the air would increase the speed of sound a bit more due to the molecular weight of water vapor that is 18gm/mol in comparison to 28.95 gm/mol for dry air. So, when taking dry vs humid air affect sound travel, decreasing it whereas humid air gets it at rising.


On the basis of the vapor pressure of water in the air, you can easily calculate the molecular weight. In addition, with an adiabatic constant of γ = 1.4, that is used for dry air on the basis of diatomic molecules n2 and o2, which is not applicable for water molecules. When discussing it in detail, it states how accurate the value of γ should be used.  To make the calculation simpler, γ = 1.4 will be adequate. 

Lastly, we can conclude to the aspect of humid air, which has more moisture within, can increase the speed of sound, whereas dry air has vice versa, as mentioned earlier in the article.