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Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538

Physics Demo Manual

Demonstrations are cataloged according to PIRA Bibliography


Due to Physics Building renovations, the lead time to set up demo requests has increased due to the need to transport equipment across campus. Please be kind and let me know well ahead of time what you need.

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 Thermal Properties Of Matter
 Heat And The First Law
 Change Of State
 Ice Bomb (expansion of water upon freezing)
 Regelation in Ice
  video  - Thermocouple in Ice
  video  - Boiling by Cooling
  video  - Boiling by Reducing Pressure
  video  - Crush the Soda Can
 Sling Psychrometer (Relative Humidity)
 Phase Change in Iron
 Kinetic Theory
 Gas Law
 Entropy And The Second Law

 video  - Boiling by Cooling


To show that water will boil at a temperature below 100C if the pressure above the liquid is reduced below atmosphere.


centered image

Bring the water in the flask to a boil, remove from heat and seal with the stopper. Let the water cool for a few seconds to make a good seal and then invert the flask as shown in the second image below. At this point, all of the air in the flask should have been replaced with water vapor from the boiling water. Placing some ice in the concave bottom of the flask causes the water vapor to condense leaving a vacuum in the flask. Once the pressure has been reduced enough, the water will begin to boil.