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Zooming in, Details and Definitions

Behaviors of gasses

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Mean Free Path

The average distance that a gas molecule can travel before colliding with another gas molecule is called the mean free path.

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Imagine the world's largest air hockey table, with a few pucks zipping about. Even if I manage to knock one puck, it is unlikely to hit any other pucks on it's way to the goal. That is molecular flow. Wind does not blow and pumps cannot suck because there are not enough molecules around for domino-chain effects to occur (like blowing out a candle). 

Vacuum Chambers

The Chamber itself

 just a box for holding nothing. 

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