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PIRA Code(s)
Set up time
5 minutes
Physics and Science Concepts
Rotational Dynamics, Conservation of Angular Momentum,
Partially fill flask with water. Attach flask by string to ring stand. Then, use a Bunsen burner or a torch to heat the flask. The flask should rotate as the steam emerges from the arm.
Use caution around Bunsen burner or torch. Do not overheat the glass as it may shatter. Eye protection should be worn. The torch can be acquired from the machine shop if necessary.

A flame torch is used to boil water inside a flask that hangs by a string. Jets of steam flow from perpendicular nozzles and rotate the flask. The flask is partially filled with water and heated until steam is produced. The steam emerges from right-angle arms on the side of the flask, causing it to rotate in the direction opposite to that of the
emerging steam