Purpose: To show that an increase in pressure on a fluid is uniformly distributed throughout the fluid (Pascal's Principle), and to show the                      principle of buoyancy.

SQUIDY cartesian diver in a 1-liter or 2-liter plastic bottle.

Squeeze the bottle to increase the pressure on the water inside the jar. This forces water into the diver and increases its density. The diver then sinks. Releasing the pressure on the bottle allows the diver to float back to the top.

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