Two crossed polarizers are placed on an over-head projector. Slides of differing materials are placed between the polarizers. They show differing colors depending on the amount of rotation of the polarization as the light goes through the materials.
1) A collection of celephane tape strips on a glass slide shows the rotation of the polarization depending on number of layers.
2) An antique flower that changes color as the polaroid filter is rotated.
3) A piece of polyethylene is placed between the polarizers and stretched producing colors as it thins out under stress.
Question?
What happens to the color of a zone when the filters are rotated 90 degrees?
Are the colors produced members of the addition or subtraction set of colors?
