Snell's Law and the Law of Reflection explain how light isredirected when it encounters a surface between two media. In theextreme, light may only reflect at a boundary, and go back into themedium it was in. More often, some of it reflects and some goesthrough. If the boundary is plane and flat, then these laws areeasy to interpret. When the boundary is curved, they describehappens at every point on the surface. One of the classic types ofglass is called \"crown\" glass, which has an index of refraction forvisible light of 1.52 and is usually free of significantimpurities. It was one of the first glasses discovered, and windowsare made from it. Another glass is called \"flint\" glass, and it haslead oxide added, which makes it heavier, more \"dispersive\", andincreases its index of refraction to 1.62. 1. A ray of light entersa flat surface of crown glass at a 25 degree angle to the surface.At what angles do the reflected and refracted rays leave thesurface? 2. As in the first part, but for flint glass, what are theangles? 3. For the flint glass, the refracted ray goes through theglass to the other side. If the glass is a parallel slab, whathappens when the ray reaches the opposite side from the inside? Atwhat angle to the surface does it exit the glass back into air? 4.What is the smallest angle to the surface that light can have andstill be transmitted from the inside to the outside in the case offlint glass? What angle is the light going at as it leaves in thatcase? Hint: The laws of reflection and refraction are usuallystated in terms of the angles to the perpendicular or \"normal\" tothe surface. These questions are rephrased in terms of the anglesto the surface so take care in interpreting the laws and youranswers.