PURPOSE: To show that air is viscous.
DESCRIPTION: A large thin disc is suspended above a copper plate mounted on a rotator. As the plate is rotated, the thin disc begins to rotate slowly in the same direction, because of drag caused by the viscosity of the air.
REFERENCES: (PIRA 2C30.10)
EQUIPMENT: Rotator, Barlowe's disc, thread, cardboard disc and stand.
SETUP TIME: 10 min.
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