2A30.13 - Surface Tension - Boat

Code Number:
Demo Title:
Surface Tension - Boat
Surface Tension
Area of Study:
Heat & Fluids
Evaporating dish, toothpicks, liquid soap, paper boat cut out of index card.

Place the paper boat in the water.  Place a drop of liquid soap on a toothpick and touch to the water at one of the edges of the boat.  The boat will seem to race away from the toothpick.

  • Billy Tolar, "Surface Tension", TPT, Vol. 26, # 9, Dec. 1988, p. 586.
  • Charles Vivian, "Propelling a Toy Boat with Detergent", Science Experiments & Amusements For Children, p. 52.
  • Janice VanCleave, "89, Spiral Whirl", Teaching the Fun of Physics, p. 133.
  • Janice VanCleave, "90, Soap Boat", Teaching the Fun of Physics, p. 134.
  • Scotty Ellerbee,  "Demonstrating Surface Tension",  PIRA Newsletter, Vol. 3, # 17, p. 7, 1/25/90. 
  • Jearl Walker, "2.150, Shaver Clippings and Camphor Boats on Water", The Flying Circus of Physics Ed. 2, p. 145.

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