2B40.57B - Buoyancy Paradox - 3 Beakers & Density Balls

Code Number:
Demo Title:
Buoyancy Paradox - 3 Beakers & Density Balls
Comparison of Weights and Densities
Area of Study:
Heat & Fluids
Three Beakers, Two Ping-Pong Balls, Two Super Balls, and Scale.

Fill one of the 3 beakers with 800ml of water. Drop the two ping-pong balls into a beaker and fill it to an 800ml level. Do the same with the remaining beaker and two super balls. When you position any of the two beakers on the scale, they should balance.

NOTE: The final adjustments in volume can be made using a water bottle.

  • Paul Hewitt, "Answer to April Figuring Physics", TPT, Vol. 58, #5, May 2020, p. 358.
  • "Hydrostatic Paradox", Pike's Illustrated Catalogue of Scientific & Medical Instruments, 1984, p. 237.

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