Thermodynamics involves the study of heat and thermal energy and its conversion into mechanical energy. Science projects using practical applications teach the basic principles of thermodynamics. These projects rely on obtainable materials and allow for post analysis to further improve comprehension. Once there is a fundamental understanding of the topic, more advanced areas can be explored.
The First Law of Thermodynamics
Teach the first law of thermodynamics using rubber bands. The first law of thermodynamics states that energy can be transformed, but not created or destroyed. Use an infrared thermometer and measure the temperature of the rubber band at rest. Next stretch the rubber band in one-minute intervals and measure the rubber band's temperature. In accordance with the first law, the work put into stretching the rubber bands converts into heat, which causes the temperature of the rubber band to increase. See how the rubber band temperature changes as a function of the number of times the rubber band has been stretched.
Teach heat capacity by comparing pure and salt water solutions. Add equal amounts of ice to each liquid bath and measure the temperature change at various time increments. Salt water has a lower specific heat value than pure water, so the temperature change of the salt water is greater for the same heat addition. Use different concentrations of salt water and measure the temperature effects. The greater the salt concentration, the greater the temperature change for equal heat additions. Calibrate the system using the known specific heat of water to calculate the heat added, then calculate the specific heat of the other saltwater solutions.
Use balloons to teach Charles's law. Charles's law states that the volume change of a body is proportional to its temperature change as long as the pressure is held constant. Blow up similar balloons to the same size and place the balloons in heated, cooled and room temperature environments. Record these temperatures for reference. As the temperature of the balloon increases so will the volume. After 15 minutes calculate the volume of the balloons by measuring their circumference. Use the room temperature balloon as a reference and measure the constant of proportionality between the volume of the balloon and the external environment temperature. Use this ratio to determine the temperature of the heated and cooled balloons and see how closely this calculation matches the actual measured temperature.
Introduce a project that measures the heat conduction through different materials. Build an adiabatic box and separate the box into two chambers using one of the chosen materials. In one chamber introduce a heat source. Measure the temperature of both chambers during the entire experiment. Using these recorded temperatures calculate the total heat transfer through the material using published values for the materials' conductivity, k. Use insulating and conducting materials and see how their material properties affect the heat transfer from one chamber to the next. For a real world application, use an air barrier between two pieces of glass to see the advantage of using double versus single paned glass windows.