Density and pressure relationship

[shellysharma]

I am not a physics person and came across this

diff (density)/diff (time) = (1/speed of sound^^2) diff (pressure)/diff (time)

I want to know what are conditions of application of this? I was advised that the equation assumes thermal equilibrium as density is a function of temperature and pressure. I want to be sure before going any further.

Many thanks

 

[vanesch]

It's explained in the wiki article: http://en.wikipedia.org/wiki/Speed_of_sound

 

[Studiot]

http://www.chem.arizona.edu/~salzmanr/480a/480ants/kapsadex/kapsadex.html