PURPOSE: To aid in describing the Cavendish experiment.
DESCRIPTION: The black (steel) balls are temporarily rigidly fixed in space. A steel barbell is mounted to a stiff wire on the axis of the barbell with a small mirror attached to the wire just above the barbell. Light reflects off the mirror, indicating the oscillations of the barbell. The equilibrium position for oscillations of the barbell shows the displacement corresponding to the gravitational force between the two pairs of balls, and is observed by noting the movement of the light refle cted off the mirror.
SUGGESTIONS: See film loop "Measurement of G," which shows measurements with a real Cavendish balance apparatus.
REFERENCES: (PIRA 1L10.20)
EQUIPMENT: Model as photographed.
SETUP TIME: None.
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