Why Is the Average Velocity of Gas Molecules Zero?

shamone
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Homework Statement



Why is <vx> = 0 this is a gas molecule

Homework Equations





The Attempt at a Solution



I don't understand how the velocity could ever be zero?
 
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The average velocity of these particles is zero, because each particle is equally likely to have a positive or negative velocity in any direction.

Actually I think this is the reason
 
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