PURPOSE: To demonstrate dramatically heating air by compression.

DESCRIPTION: A small piece of cotton is pushed into the bottom of the tube using the wire provided, and the plunger is sealed into the tube, as seen in the photograph above. The plunger is pushed down sharply, compressing and thereby heating the air within. The temperature rises high enough to ignite the cotton with a flash, which can be readily seen through the plastic tube.

Click your mouse on the photograph at the left above to see an mpeg video of the demonstration. The photograph at the right shows the amount of cotton that is best used for the demonstration; a greater amount will not work because the cotton cannot be raised to its kindling temperature. Click here to see an earlier version of the demonstration, which is no longer available.

SUGGESTIONS: Practice before class.

REFERENCES: (PIRA 4B70.10)

EQUIPMENT: Fire syringe with accessory parts as photographed.

SETUP TIME: None.