Solving Ideal Gas Law Model Homework

AI Thread Summary
The discussion centers on the confusion regarding the derivation of the Ideal Gas Law, specifically the use of traveling time versus impact time in calculating force. It is noted that using impact time would result in an excessively large force due to its small duration. Participants agree that the impact time of a gas molecule is negligible compared to its travel time after rebounding. This distinction is crucial for accurately modeling gas behavior. Understanding these timeframes is essential for solving related homework problems effectively.
Andy123
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Homework Statement


My problem is with the last line of the derivation. Usually, we take the rate of change of momentum (force) to be change of momentum divided by the impact time. But this slide of pp showed that the traveling time of the particle in the box is used but not the impact time. Why is it? Appreciate any comment on this. Thank you!

Homework Equations

The Attempt at a Solution


I realized that if the impact time is used. The force will be very large since the impact time is likely to be very small.
 

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Andy123 said:

Homework Statement


My problem is with the last line of the derivation. Usually, we take the rate of change of momentum (force) to be change of momentum divided by the impact time. But this slide of pp showed that the traveling time of the particle in the box is used but not the impact time. Why is it? Appreciate any comment on this. Thank you!

Homework Equations

The Attempt at a Solution


I realized that if the impact time is used. The force will be very large since the impact time is likely to be very small.
Do you think the impact time of a gas molecule will be a significant fraction of the travel time of that molecule after it rebounds?
 
No, it should be a very small fraction.
 

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