Polariscope / Polarimeter

An easy-to-assemble polarimeter, which lets you observe the effects of optically active materials (like sugar water) and birefringence (like in clear plastics). The outer dial has markings in 5 degree increments, and the vernier scale on the inner dial can be used to get down to 0.5 degree resolution. Some experiments you can do with this:Start with the dial at 0 degrees and observe how the brightness of the light changes as the dial is turned. Try measuring (or estimating) the brightness at evenly spaced angles to try and figure out the relationship. The true value is dictated by Malus' law, which says it is proportional to cos^2(θ), where θ is the readout of the dial. Set the light to Red. Adjust the dial to 90 degrees so all of the light is blocked. Place a glass of an optically active substance (like sugar water) in the polarimeter and observe that some light is visible again. Adjust the dial until all the light is blocked again: this difference is the angle by which the substa