PURPOSE: To determine the mechanical equivalent of heat.
DESCRIPTION: Turning the handle with weights hanging from a cord wrapped around the copper cylinder requires a calculable amount of mechanical energy. This energy is converted into heat in the copper cylinder and the water bath, raising their temperature. The constant of proportional, which is the mechanical equivalent of heat, can be calculated using these two measurements. The device counts turns, so you can continue to lecture while cranking, typically 100-150 turns. The result is generally good to better than ten percent.
REFERENCES: (PIRA 4B60.00) See Demonstration Reference File for sample data and details in the procedure.
EQUIPMENT: Joule's apparatus for mechanical equivalent of heat, digital thermometer.
SETUP TIME: 10 min.
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