4A40.31 - Liquid Nitrogen - Whack A Penny
See also 4A40.31 in Heat and Fluids
Cool the pennies in the liquid nitrogen using the tongs. Put on the safety glasses, place the penny on the lead brick, and give it a good whack. The penny should shatter into several pieces due to the physical changes to the Zinc's crystal structure when cooled with the liquid nitrogen. Note: Newer pennies are used because they are mostly Zinc with a thin coating of Copper.
- William McNairy, "Baffling Buoyancy", 2008 AAPT/PIRA Apparatus Competition, An Entry for the Low Cost Category.
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