PURPOSE: To demonstrate the concept of equipartition of energy.
DESCRIPTION: Into the glass bowl are placed balls of the same size but three different masses: ping pong balls, cork balls, and superballs. Shaking the bowl gives all of the balls approximately the same kinetic energy. Because the light balls have greater velocities for the same average kinetic energy, as you shake the bowl more and more fervently first the ping pong balls, then the cork balls, and finally the superballs jump out.
This is the argument of equipartition of energy applied to molecules of gas in the atmosphere that would cause lighter gases to leave the earth's atmosphere before heavier gases.
REFERENCES: (PIRA unavailable.)
EQUIPMENT: Bowl with three ping pong balls, three cork balls, and three superballs.
SETUP TIME: None.
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