2 plastic cups filled with water
One plastic cup floating in another plastic cup

 

Code Number: 2B40.25

Demo Title: Battleship in a Bathtub

Condition: Good

Principle: Buoyancy

Area of Study: 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.