“Jay Just Amazes Me During
This, He Really Does. ”
“OK, there you go. It's sensitive!” Jay pushes up on the rubber sheeting of his newly completed “Australian” CDS, in which the entire system is inverted. To operate this system, one pushes up on the rubber sheeting while the diver floats at the top (what used to be the bottom) of the inverted test tube. As in the regular CDS, this causes the water to enter the diver, compress the air therein, and begin to sink the diver. Exploration of the Australian CDS marks the beginning of the students' second cycle of investigation, in which they typically explore the same phenomena in a different context to refine their understanding of it. Jay holds his system up for Laura, who is leaning over his desk to watch Jay and Ned working, to examine.
“Well, you had to push pretty hard, didn't you? It still works, you can watch what happens. But when you push that hard that means, ” Laura tries to explain to Jay that his system is not actually sensitive. She takes the system from his hands and holds it in front of him, demonstrating how hard she has to push to operate it. As she pushes up, he peers intently at the diver.
“It was gettin'in! The air is going up there!” Jay points to the air within the diver as the water compresses it. Although he had articulated ideas about pressure previously, the second cycle, with a slightly different and less sensitive system, seemed to support his observation and description of different details of its operation.
“Well, when you do your writing you're gonna want to record that. Talk about exactly what happens when you press, what did you see going on?” Laura turns away from the system to look at Jay.