2A10.05 - Surface Tension - Pennies in a Cup

Fill a plastic cup to the very top so that there is a visible meniscus showing above the rim of the cup.  Start dropping pennies into the cup.  See how many pennies it takes before the water spills out of the cup.
Code Number:
2A10.05
Demo Title:
Surface Tension - Pennies in a Cup
Condition:
Excellent
Principle:
Surface Tension
Area of Study:
Heat & Fluids
Equipment:
Clear plastic cup, Water, Pennies.
Procedure:

Fill a plastic cup to the very top so that there is a visible meniscus showing above the rim of the cup.  Start dropping pennies into the cup.  See how many pennies it takes before the water spills out of the cup.

References:
  • Robert Ehrlich, "H.16, Dropping Pennies into a Water-Filled Cup", Turn The World Inside Out, p. 110.
  • Bobby Mercer, "Super Wet Penny", Junk Drawer Chemistry, 2016, p. 32.
  • Tik L. Liem, "How Many Pennies Can Go In", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 44.
  • Julius Sumner Miller, Q126 & A126, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 18 & 80.

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