PURPOSE: To demonstrate that bodies that fall with unequal accelerations in air fall with the same acceleration in the absence of air.
DESCRIPTION: The ball falls faster than the feather with air in the tubes. When the air is pumped out, the ball and the feather fall with the same acceleration. The double tube assembly is rotated rapidly on its axis to initiate the free fall.
REFERENCES: (PIRA 1C20.10)
EQUIPMENT: Vacuum pump with double tube assembly, as photographed.
SETUP TIME: None.
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