Collision heat model
Introduction/Discovery Question
When you hit something, what happens to the energy?
This activity uses a model of a hammer colliding with a solid to explore what happens to the molecules.
You may know that when something is hit or squeezed, it heats up a bit. You have actually measured this effect if you did the Heating by hitting activity. But what is heat, and how does the motion of a hammer get changed into heat energy?
Procedure
Here is a picture of a wall of atoms. The yellow object represents a hammer head. It will move to the left and hit the atoms. Describe what you think will happen. Make a drawing of what will happen to the atoms.
Collect Data
- Below is the Hammer model. The white circles represent atoms. When they move, they turn red.
- Run the model using the controls below it. Describe what happens to the hammer and the atoms.
- Note the temperature graph on the right. What physical process does temperature measure?
- Reset the model and run it again. Write down the average temperature of the atoms after the collision.
- Reset the model, change the hammer velocity, and run it again. Write down the average temperature of the atoms after the collision.
- Repeat this measurement for other velocities.
- Run the model one more time. Click on Pause after the collision. Then play the model backwards.
Analysis
1. Make a chart comparing the hammer velocity to the temperature of the atoms after the collision.
| Hammer velocity | Temperature |
|---|---|
| 5 | |
| 10 | |
| 15 | |
| 20 |
2. Which would you say is more correct?
- The temperature is proportional to the velocity (momentum of the hammer).
- The temperature is proportional to the square of the velocity (energy of the hammer).
3. In a collision, the kinetic energy of the hammer changes into kinetic energy of the molecules. What is different about these two forms of kinetic energy?
4. Describe what happens when you run the model backwards. Does this process ever happen in nature?
Conclusion
If you rub a penny very energetically, it will heat up. How is that process similar to this Hammer model? How is it different?
Further Investigation
Change other variables in the model, such as the mass of the atoms, and discuss the effects you observe.
SensorPortfolio© 2005-2006 by the Concord Consortium, developed by the TEEMSS2 project.
This activity was created by itest itest using the ITSI Do It Yourself portal.
This copy of the activity works with Vernier Go! Link probeware. If you want to use this activity with a different probeware interface open this web page: Collision heat model, select another interface and Run the activity again.