This module has been the most exciting for the students to learn, all because of Experiment 6.2: A Simulation of Plastic Rock.
Plastic Rock – Rock that behaves like something between a liquid and a solid. It is in the astehenosphere.
This experiment is made with a mixture of cornstarch and water. First you mix a portion of water and cornstarch together in a pan. I found in my cabinets two old round cake pans that worked really well. The high sides kept the mixture inside the pan, well most of it.
Here is a helpful tip. Put paper or cloth down on the table before opening the cornstarch. This is for easier cleaning later. As you can see in the picture above and below, just looking at cornstarch makes it go all over the place.
After mixing water and cornstarch, you want to get a nice smooth gravy and then add more cornstarch.
Below the young men are trying to mix the cornstarch at the beginning. It is difficult at first, but they keep at it.
This was not fun part!
The fun part was playing with it. 😀
When plastic rock is hit by a force it becomes a solid. When left alone to relax, it becomes a liquid. The young ladies above are spooning it out, which causes it to solidify and then it relaxes and drips off the spoon.
The young men are showing the same results above. Notice that the young ladies use spoons and the young men are using their hands. LOL That doesn’t last long. Take a look at the next picture.
All three of the young ladies got their hands in it and didn’t want to stop playing with it. Squeals of delight were heard! Notice the blob on the right is hard, while the one in the center is slowly beginning to droop. Cool, don’t you think?
Above is another picture of the young ladies. Look at those faces. All three of them are just lovely and they had the best time. I have great students.
Because this experiment took a little longer than others and because no one wanted to stop playing with it, we had time to do only one other experiment.
Check out Sahm I Am post on this experiment.