PURPOSE: To illustrate the effect of moment of inertia on rolling acceleration.
DESCRIPTION: Roll two identical cans from rest down an incline, where one is empty and the other is nearly filled with water. Q: Which gets to the bottom first, or is it a tie? A: The water-filled can reaches the bottom first. Due to its small viscosity, the rotation of the water is limited, and that can acts much like a body sliding without friction down the incline. Using the broom, give the two cans a push up the incline. Which can will roll higher up the incline?
REFERENCES: (PIRA 1Q10.50)
EQUIPMENT: Tilting hospital cart, push broom, two cans, one mostly filled with water.
SETUP TIME: 5 min.
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