Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] speed of sound



And, of course, solid CO2 won't do, as there'll be a temp. gradient, tho it'll purge quicker.

Same problem if one tries butane.

bc

p.s. Haven't checked methane, but you've a big supply, and at room temp.



Edmiston, Mike wrote:

Here is an expansion on what John Mallinckrodt said, and also
explanation of some other problems.

The usual formula for the speed of sound in a gas that behaves as an
ideal gas (in terms of PV = nRT) is...

V = sqrt(gamma*R*T/M)

R is the gas constant 8.314 J/mol.K
T is Kelvin temperature
M is the molar mass in kg. For CO2 this is 0.04401 kg/mol
Ignore gamma for a minute.

If Vo is the reference velocity at the reference temperature (To),
then...

V/Vo = [sqrt(gamma*R*T/M)]/[sqrt(gamma*R*To/M)]

V/Vo = sqrt(T/To) assuming gamma, R, and M are constant.

V = Vo*sqrt(T/To)

Which the formula John M. provided.

Gamma is the ratio of specific heat at constant pressure to specific
heat at constant volume. Theoretically Cv is f/2*R where f is the


a lot cut