Is F in P=F/A an average or a sum of all microscopic forces?

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SUMMARY

The force F in the pressure formula P=F/A is definitively an average of all microscopic forces exerted by gas particles on the container wall over time. This average accounts for the individual forces from each particle, which are summed to determine the total force. The averaging process smooths out random fluctuations caused by particle collisions, providing a more stable representation of pressure. Thus, the interpretation of F as an average rather than a simple sum is accurate and essential for understanding gas behavior.

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  • Understanding of basic physics concepts, particularly pressure and force.
  • Familiarity with gas behavior and kinetic theory.
  • Knowledge of statistical mechanics principles.
  • Basic mathematical skills for averaging and summation.
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  • Explore the relationship between microscopic particle behavior and macroscopic properties like pressure.
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Greg777
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Hello,
I've read that the force F we use in the pressure formula P=F/A is an average of all microscopic forces exerted by the gas on the wall of the container over a period of time. Is it true? I thought it was a SUM rather than an average?
I assume that in that definition the microscopic force is a force exerted by a SINGLE particle on the wall.
 
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It's a sum over all the different particles, but an average over time. When the text talks about averaging, it should be talking about averaging over time to smooth out the random fluctuations of collisions with particles.
 
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