When you start, you will see a blank worksheet like Figure 1. You will see seven square objects called 'agents' in a 'Gallery' across the top and eight tools arranged vertically on the left. At the bottom there is a 'run' button. Click on it to run the model.
You can put any number of the agents in the worksheet. Click on the agent and on the pencil tool. Then anywhere you click in the worksheet will create the agent. Move objects around with the arrow tool. Eliminate them one at a time with the eraser tool. Create a rectangle of the same objects with the shaded rectangle tool. Erase a rectangle of objects with the white rectangle tool. Ignore the finger, hammer, and question tools, as they are not used in this activity.
Play around making and erasing different patterns. What happens if you pile up two or more agents on top of each other? Try erasing this 'pile' - you have to erase them one at a time.
Start by putting one 'Arrows' agent in the worksheet and pressing the 'run' button. Be sure the run button turns green--this may take a while.
Put a good conductor next to a hot agent. Move it away. What do you see? Put the good conductor next to a cold agent. Move it away. Repeat with a poor conductor and an insulator.
Make a horizontal row of nine good conductors and place a graph under each. Put a hot agent at one end and a cold one at the other. In a short time, the conductors shade from red to blue. The steps will be 10 C apart.
Try to answer the question, 'What happens when you mix things with different temperatures?'
First, make a row of nine good conductors with H on one end and C on the other. Use this to estimate temperatures, since it shows colors for each 10 C step from 0 C to 100 C.
Set one good conductor agent at 100 C by touching it to an H agent and then
removing it. Make a second good conductor agent 0 C touching it with a C agent.
'Mix' these two blocks by placing them next to each other. From the resulting
color, estimate their final temperature. See Figure 2.
Predict what will happen in each of the following cases, and then try each:
Figure 3 shows a way to simulate a finger touching aluminum, wood, and
Styrofoam. The H, poor conductor, and good conductor on the left represents
your finger, while the block of nine agents represents aluminum. The H
represents your hot blood. The poor conductor represents flesh. The good
conductor represents your skin, which is where you sense temperature. The row
of C agents keeps the aluminum cold.
Run the simulation and then touch the aluminum by moving the good conductor as indicated in Figure 3. Just below it a graph indicates the temperature that you will sense. What happens?
Predict what will happen in each of the following cases, and then try each:
Let's see whether an insulator is better at keeping things hot or cold. Draw a rectangle of six good conductors to represent a can that you want to keep cold. Surround it with a layer of insulation. Surround that with a layer of H agents, representing the summer sun. Place a graph in the can to monitor its temperature.
Put a C on top of the can until the entire can is cold. Then remove the C and estimate how long it takes the can to get to 50 C. (When a new conductor agent is made it is at 50 C, so a new block not touching anything can be used to generate the color corresponding to 50 C.)
Predict what will happen in each of the following cases, and then try each: