Purpose:Demonstrate explicitly how a cartesian diver works by showing how the water enters the diver when the pressure in the cylinder is increased.
Description:When no additional pressure (above normal atmospheric pressure) is applied to the membrane on top of the cylinder, the diver floats at the surface of the water. The location of the water surface inside the diver is indicated by the orange bob floating in the diver tube. When additional force is applied to the membrane the pressure in the tube increases, forcing more water into the diver tube and compressing the air in the tube, as indicated by the bob. Because the average density of the diver becomes greater than that of water, the diver sinks to the bottom. When the force is released, the diver again rises.