# Lab Essay

256 WordsMay 31, 20092 Pages
In this lab we determined the index of refraction of a glass plate. The materials used in this lab were a glass plate, He-ne laser, ruler, protractor, and a calculator. The procedure starts by stacking sheets of paper and magazines so that the laser beam is just above the paper. Outline the glass plate on top sheet of paper. Then draw a normal line from the center of an edge of the glass plate. Shine the laser beam so that it marked an angle of incidence of about 20 degrees from the normal and hits the plate where the normal intersects the plate. Make sure that you mark the points where the laser beam touches the paper, where the plate exists and where it leaves the paper. Label this ray “A”. Next move the beam to about ten other angles on both sides of the normal. In each case the beam should hit the plate where the normal intersects the plate. Again make sure that you mark the points where the beam touches the paper, leaves the plate and leaves the paper. Label each of these rays. Make sure you go to as large angles of incidence as possible. Remove the glass plate and connect the paths of all the rays from one side of the paper to the other. Use a sharp pencil. Measure the angle of incidence and angle of refraction for each ray. Finally, using one of the glass prisms, repeat the previous steps for at least two rays entering and exiting the