Kinneret Day School’s seventh grade science classes took a deep dive into the study of density, buoyancy, air pressure, compression and the different characteristics of air vs. water. Science teachers Lynne Fried-Whyne and Leslie Wachtel, along with CIJE Coach Rabbi Heshy Wieder, had students learn about these forces through a hands-on experiment using the principle of buoyancy (Archimedes’ principle) and creating their own Cartesian Divers.

Using one liter bottles, plastic droppers or pipettes and a hex nut, students created and fine tuned their diver density by adding water and pressure. The students quickly learned that as they squeezed the sides of the bottle, they increased pressure on the liquid inside the bottle. That increases pressure on the “diver.” If they squeezed hard enough, more water would be forced up inside the diver while the air was compressed, forcing the diver to submerge. Since water is denser than air (gas), the increased density makes the diver go down. Exclamations of excitement and “Wow! Unlike the air, the water can’t be compressed!” and “The water has no place to go but in!” were heard around the classroom. Kinneret student scientists are looking forward to creating more experiments with these divers as they further explore these concepts.