New Orleans:
Ten-Minutes-Talk
I will present two teaching aids, which can help students explore the mathematical theory of the rainbow. An interactive computer demo (in Cabri) enables the student to investigate the path of rays of light in a raindrop for different indices of refraction. Then the student can experiment with a spotlight, a cardboard screen and a spherical bottle filled with water as a three-dimensional model of the raindrop. This experiment is based on an idea of Marcel G. Minnaert (1893-1970) of Utrecht. From here it is a small step to the explanation of the rainbow. The teaching aids are part of my M.Sc. work in mathematics education, and they can be used at early undergraduate level and in the mathematics and physics curriculum of the final year of the Dutch highschools.
The text: text.pdf
Sheet of the raindrop: sheet1.pdf
Sheet of the angle: sheet2.pdf
Sheet of the maximum of the angle (arcsin): sheet2a.pdf + arcsin.pdf
Sheet of some path of rays of light in a raindrop: sheet3.pdf | sheet3a.pdf
Applet of the raindrop: applet1
Applet of the angle: applet2
Photo's of the experiment tools: sheet1.jpg
Another photo of the experiment tools and a close-up of the spectrum: sheet2.jpg
Photo's of the first place of braking the rays of light: sheet3.jpg
Photo's of the second place of braking the rays of light: sheet4.jpg
Photo's of the third place of braking the rays of light: sheet5.jpg
