PURPOSE: To demonstrate the pressure in a water column.

DESCRIPTION: Two plastic bottles are connected by a plastic tube and the entire system is mostly filled with water. Holding either of the two bottles up in the air causes that bottle to collapse. The bottle at the right was held in the air before the picture was taken.

SUGGESTIONS:

REFERENCES: (PIRA unknown.)

EQUIPMENT: Two 2-liter soda bottles filled with water connected by tubing.

SETUP TIME: None.