2B40.29 - Buoyancy vs. Surface Area

Code Number:
Demo Title:
Buoyancy vs. Surface Area
Area of Study:
Heat & Fluids
1 ft square Plexiglas water tank, Styrofoam boat with aluminum blocks.

Carefully place the Styrofoam boat in the water with the aluminum blocks toward the top.  When balanced correctly the boat should float with the top edge of the Styrofoam at water level.  Flip the boat over and see that the Styrofoam block is now out of the water about 1/2 inch.  This is due to the additional surface area added by the aluminum blocks.

  • M.J. Clouter, "Archimedes' Principle:  A Classroom Demonstration with a Twist", TPT, Vol. 44, # 1, Jan. 2006, p. 46.
  • "Figuring Physics", TPT, Vol. 41, # 8, Nov. 2003, p. 494.
  • "Figuring Physics", TPT, Vol. 27, # 4, Apr. 1989, p. 312.
  • "Figuring Physics", TPT, Vol. 25, # 4, Apr. 1987, p. 244.
  • Stavros Theodorakis, Charalambos Aristidou, "The Paradox of the Floating Candle That Continues to Burn", Vol. 80, # 8, August 2012, p. 657.
  • Jearl Walker, "2.44, Floating Bars and Open Containers", The Flying Circus of Physics Ed. 2, p. 100.
  • "88, The Passenger Rock",  Christopher P. Jargodzki and Franklin Potter,  Mad About Physics, p. 30, 88.
  • 26, "Floating Boat", Janice Van Cleave's, Physics for Every Kid, p. 62.

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