Dimensional Analysis of pV and Kave: Are They Equivalent to Work?

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The discussion focuses on demonstrating that the expressions pV and Kave share the same dimensions and are equivalent to work (W). Participants clarify that the task involves using the definitions of pressure (P) and average kinetic energy (Kave) to show dimensional consistency. It is emphasized that the units for volume should be in cubic meters, while noting that the number of molecules (n) is dimensionless. The conclusion is that both pV and Kave ultimately align with the dimensions of work. Understanding these relationships is crucial for solving the problem effectively.
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"pV=(2/3)NKave
where p is pressue.v is volume. n is the number of molecules. Kave is the average kinetic energy of each molecule.useing the definitions of P and Kave.
show that pV and Kave are the same dimensions. and that these are the dimensions of work W"

I am just unsure of what this is really asking me to do. Do i use formulas such as
P=F/A and K=1/2m^2 or simple word by word definitions.
any help would be good. thank you.

andy
 
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mrandymcnutt said:
"pV=(2/3)NKave
where p is pressue.v is volume. n is the number of molecules. Kave is the average kinetic energy of each molecule.useing the definitions of P and Kave.
show that pV and Kave are the same dimensions. and that these are the dimensions of work W"

I am just unsure of what this is really asking me to do. Do i use formulas such as
P=F/A and K=1/2m^2 or simple word by word definitions.
any help would be good. thank you.

andy

The question is only asking for dimensions. What units are you using? Is volume in meters cubed? Substitute these in the formula (n has no units BTW). The two sides should be the same and equal to the units associated with W.
 
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