Discussion of the section on light energy Discuss some of these questions with the people in your group:
  1. If you wanted to use solar heating to keep your house warm, would it help to use large converging lenses as windows?   Would there be any point to using diverging lenses?
  2. The heating coil of an electric stove gives off a lot of energy in the form of infrared light.  You can detect it with your hands and face, and can make shadows that you can detect this way.  Discuss how you could use the liquid crystal sheet to show that the infrared light is reflected by a mirror and focussed by a lens. Would glow-in-the-dark paper work, too?
  3. The blank parts of a newspaper will turn yellow if you leave it in the sun all afternoon.  Design an experiment to show that this is caused by light (instead of some other aspect of being outside or elapse of time).   Design another experiment to test the possibility that ultraviolet light is an important cause.   If the sun is shining, you might try doing the experiments!
Please send us your discussion of two of these questions.  Don't forget to tell us who is in the group.
If there is something that you don't understand about light energy, Ask us!
Please note that the activities in this section are written up (in slightly different form) in the manual (in the Light Energy section).
This is the end of this section.
Summary of the Virtual Workshop on Light