2B40.25 - Battleship in a Bathtub

Fill one plastic cup 1/4 full of water.  Fill the other cup 3/4 full with water.
Float the 3/4 full cup in the 1/4 full cup.  Spin the 3/4 cup to show that it is really floating in the less full cup
Code Number:
2B40.25
Demo Title:
Battleship in a Bathtub
Condition:
Good
Principle:
Buoyancy
Area of Study:
Heat & Fluids
Equipment:
Plastic see through cups.
Procedure:

Fill one plastic cup 1/4 full of water.  Fill the other cup 3/4 full with water.  Float the 3/4 full cup in the 1/4 full cup.  Spin the 3/4 cup to show that it is really floating in the less full cup. 

References:
  • Armand Le Noxaic, Kamil Fadel, "How to Use the Archimedes Paradox for Educational Purposes", TPT, Vol. 60, #2, Feb. 2022, p. 137.
  • I. Richard Lapidus, "Problem:  Floating Sphere", AJP, Vol. 53, # 3, p. 269, March 1985.
  • I. Richard Lapidus, "Solution to the Problem on Page 269", AJP, Vol. 53, # 3, p. 280, March 1985.
  • R. E. Benenson, "Direct-Reading Archimedes' Principle Apparatus", TPT, Vol. 13, # 6, Sept. 1975, p. 366.
  • F-130:  "Ship in a Liter", DICK and RAE Physics Demo Notebook.
  • R. D. Edge, "String and Stick Tape Experiments", "Battleship in the Bathtub", TPT, Vol. 28, # 7, Oct. 1990, p. 510.

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