2B40.41a - Buoyancy Paradox

Code Number:
Demo Title:
Buoyancy Paradox
Buoyancy, Volume, & Density
Area of Study:
Heat & Fluids
Water Filled Tank and Paradox Apparatus.

Hang the paradox apparatus on a horizontal bar with a hook on it.  Place the apparatus in balance by adjusting the distance of each ball from the center.  Since one ball is 1/2 the density of the other the distance from the center of the arm should be a 1:2 ratio.  Each ball has the same volume however when dipped into the water the equilibrium is disrupted.

  • Paul Hewitt, "Figuring Physics", TPT, Vol. 27, #6, Sept. 1989, p. 496.

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