4A40.20 - Liquid Nitrogen - Banana and Mercury Hammer

Arrange ahead of time to get liquid nitrogen from either Biochem Stores .
Typically it takes about 4 liters for each classroom demonstration.  Freeze a banana and you can drive nails with it.  The fibrous nature of the banana keeps it from breaking apart easily.
Directions for the Mercury Hammer can be found in the files or the hardcopy 4A40.20 entry.
The temperature of liquid nitrogen should be a -196o C or approximately 77o K.
Code Number:
4A40.20
Demo Title:
Liquid Nitrogen - Banana and Mercury Hammer
Condition:
Good
Principle:
Properties of Liquid Nitrogen
Area of Study:
Chemistry and Physics
Equipment:
Liquid Nitrogen, Dewars, Plastic Beakers, Mercury, Paper Cup, Tongs, Bananas, Nails and Boards.
Procedure:

See also 4A40.20 in Heat and Fluids

Arrange ahead of time to get liquid nitrogen from either Biochem Stores . Typically it takes about 4 liters for each classroom demonstration.  Freeze a banana and you can drive nails with it.  The fibrous nature of the banana keeps it from breaking apart easily.  

Directions for the Mercury Hammer can be found in the files or the hardcopy 4A40.20 entry.  

The temperature of liquid nitrogen should be a -196o C or approximately 77o K.

References:
  • Hk-7, 8:  Freier and Anderson, A Demonstration Handbook for Physics.
  • H-078:  "Objects in Liquid Nitrogen",  DICK and RAE Physics Demo Notebook.
  • Mike Walker, "Cold, Hard Facts", Popular Science, June 2009, p. 74.
  • Gordon McComb,  Lasers, Ray Guns, & Light Cannons - Projects from the Wizard's Workbench, pp. 28.


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