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This should be a pretty simple problem to answer... I'm just a bit confused on this, and want to make sure I'm right. It's an easy problem:

Molecules in a gas can only move in the x direction (i.e., [tex]v_{y}=v_{z}=0)[/tex]. You set up an experiment in which you measure the velocity of a few molecules and the result that you obtain is the following (expressed in m/s):

2, -4, 6, 1, -3, -2, -5, 2, -1, 4, 3, -5

Calculate: a) the average x-component of the velocity [tex](v_{x})_{av}[/tex], b) the average speed [tex](v)_{av}[/tex], and c) the root mean square of the velocity [tex]v_{rms}[/tex]

For a), the x-component of velocity is literally just the average, right? No absolute values b/c we're not talking about speed here.

For b) because I'm being asked for the averagespeed, here is where I take the absolute values of all of these and average them together, right?

For c) This is where I'm most confused... Here, wouldn't I just square what I got for b) and then take the square root of it? That seems to make absolutley no sense. Would I then use the formula below?

I noticed something in the book: [tex](v_{x}^2)_{av}, (v_{y}^2)_{av}, (v_{z}^2)_{av}[/tex] must all beequal. Hence: [tex](v_{x}^2)_{av} = \displaystyle{\frac{1}{3}}(v^2)_{av}[/tex]

This wouldn't apply for this situation, correct? As the y and the z components are 0, right?

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# Kinetic-Molecular Model of Ideal Gas: vrms/vav

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