Calculate RMS Velocity of Air at 72 cm-Hg, 344.7013 m/s, 22.6 C

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    Air Rms Velocity
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To calculate the RMS velocity (Vrms) of air at 72 cm-Hg pressure, 344.7013 m/s sound velocity, and 22.6°C temperature, the relevant equation involves the relationship between these variables. The user struggles with assigning values correctly in the equation, particularly regarding the terms "velocity" and Vrms. There is a suggestion to consult a textbook for an alternative equation that connects Vrms and temperature. Clarification is sought on the definitions of n, Na, and m in the context of the equation. Understanding these components is crucial for accurately calculating the RMS velocity.
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Homework Statement


If the air pressure is 72 cm-Hg (as measured with a barometer), the velocity of sound is 344.7013 m/s and the temperature is 22.6 C calculate the Vrms.


Homework Equations



velocity = Vrms*sqrt[(1.40*n*Na*m)/(3*density*Vol)]

The Attempt at a Solution



I am under the impression that the Nam cancels out the density*volume, but I'm not getting the right answer. I'm really having trouble assigning values for all the parts of the equation.

Thanks in advance.
 
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If the quantities are what I think they are***, then n*Na*m would cancel density*volume. This will leave an equation with two quantities, "velocity" and "Vrms". I know what Vrms is, but have know idea what "velocity" refers to in this equation.

Hint: can you find a different equation in your textbook, one that involves both Vrms and Temperature?

*** p.s. correct me if I'm wrong, but I believe that:
n is the number of moles of air molecules
Na is Avagadro's number, 6.02 x 10^23
m is the mass of a single molecule.
 

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