Think About It 1. Why do you feel warmer in the sun than in the shade, when the temperature of the air is the same?
2. If you could only heat one floor of a two-story house in the winter, which floor would you heat? Why?
3. If you burn toast in the kitchen, why can you smell it all over the house?
4. Why do workers in the tropics wear long-sleeved, light-colored clothing?
5. Why does the wind tend to blow inland from the ocean during daylight hours?
Experiment With It Let’s investigate radiation and convection.
Objectives Students will be able to describe the transfer of energy by radiation. Students will be able to describe the transfer of thermal energy by convection in liquids and gases.
Hypothesis Using an “if…then…because…” format, construct a hypothesis describing how thermal energy is transferred in gases and liquids.
Materials Part I - Radiation
Part II - Convection in Gases
Part III - Convection in Liquids
Black and silver radiation cans Thermoconductivity strip 2 Thermometers Radiation source (infrared lamp) Index card Tape Watch with second hand Ruler
Thermoconductivity strip Candle or alcohol lamp Matches
U-tube Water Food coloring Ring stand with clamp Candle or alcohol lamp Matches
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Thermodynamics