The Greenhouse Effect Conceptual Physics Text Correlation: Section
Question 1 To keep the interior of a car from heating too much, it is common to put a reflecting surface behind the windshield. How does this work? Answer: Light does not change frequency when reflected (a blue shirt is still blue in a mirror!).So light that has a frequency to get through glass in the first place will reflect back through the glass. Light that gets absorbed, however, is not reradiated at the same frequency. The reemitted light has a frequency proportional to the temperature of the emitter. The low frequency of this reradiated light keeps it from getting through the glass.
Question 2 Is the greenhouse effect something the world would be better without? Answer: No! Without the greenhouse effect, the world's average temperature would be a frigid -18°C. The environmental concern is too much greenhouse effect.