UTF-8Atomic gas laws
This model is intended to clarify how the motion of atoms influences gas pressure, temperature, and volume.
About the model
A grey piston is free to move left and right. It has a force to the left that you can control with the pressure slider (once I get it working.)
The piston and all the atoms obey Newton's Laws.
Volume is the area to the left of the piston.
Temperature is the average kinetic energy (KE) of the atom(s).
Pressure is caused by the force on the piston.
The total energy of the atoms and piston is constant (unless you add or remove KE).
Explore how pressure, the number of atoms, and temperature (average KE) influence the volume.
[Some suggested activities.]
Run the model with just one gold ball. Note carefully how the the ball speeds up and slows down.
Use the "Slow Motion" button and watch carefully what happens to the ball's speed and KE when it hits the piston.
Answer the following
1. Where is the piston when the ball is moving fastest?
2. Where is the piston when it is hit most often and hardest?
3. When the piston is moving left and a ball hits it, what happens to the ball speed?
4. When the piston is moving right and a ball hits it, what happens to the ball speed?
5. How does the piston change the energy of the ball?
6. Explain in your own words why the piston bounces in and out.
Stop the model and use middle tool to add four more gold atoms. How does this change your answers to 1-6?
Erase the gold balls and use the right-hand tool to drop a large number of small green atoms into the model.
How does this change your answers to 1-6?
Using this model explain:
1. How does a change in pressure affect the temperature?
2. How does a change in pressure affect the volume?
Note: To explore a system like this with four of variables (T, P, N, and V) it is a good idea to hold two constant and see how the other two vary. The model on this page did NOT do that. (It held N and the total energy constant). In the following pages, we will be more systematic. We will explore the following pairs of variables:
[I forget which is which]
Questions for Qian:
1. Why doesn't the script work for the pressure slider? Can you fix it?
2. Why are the heating and cooling buttons so ineffective for the gold atoms?
3. Can I duplicate this model further down the page? I'd like to save the effort of making a similar model.
4. When I reset the model, the "slow motion" checkbox is forgotten.
5. Is there a way of making a button that stops the obstical? I didn't see a variable for its velocity.
6. Can I make a button that adds atoms at the same temperature as those already in the model?
Thanks.
Bob
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