How a polarimeter works скачать в хорошем качестве

How a polarimeter works

We made a polarimeter using two linear polarizing filters and a overhead projector as a light source. By adding a glass cylinder filled with a chiral compound (galactose is shown) the plane of polarization of polarized light is rotated. This is shown by seeing the reduction in light as the polarizing filter is rotated from 90 degrees and the light minimizes at some angle from 90. A polarimeter could work in theory by either measuring the light transmitted before and after the sample is added or by testing the amount of rotation needed to achieve a minimum of light transmission. Sucrose can also be used, but the solutions need to be dense and the samples need to have enough length to give a noticeable rotation.