PURPOSE: To show polarization effects for light reflection off various surfaces, and to demonstrate the Brewster angle.
DESCRIPTION: Light from a bright point source with a condenser lens and iris is passed through a polarizer and reflected off either a dielectric or a metallic surface onto a nearby screen. Reflection off the metalic surface is unpolarized. Polarization of light reflected off a dielectric surface can be shown as follows: The polaroid is set so that only horizontally polarized light passes to the dielectric reflector. As the dielectric reflector is rotated, the intensity will decrease to zero as the Brewster angle is passed. Removing or rotating the polaroid sheet verifies this result.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Bright point source with condenser lens and iris, mounted calibrated polarizer, rotatable and removable dielectric (lucite) and conducting (aluminum) surfaces.
SETUP TIME: 5 min.
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