[SOLVED] Max angle of incidence...help! 1. The problem statement, all variables and given/known data A 1-cm-thick layer of water stands on a horizontal slab of glass. Light from a source within the glass is incident on the glass-water boundary. What is the maximum angle of incidence for which the light ray can emerge into the air above the water? (Give your answer in degrees.) 2. Relevant equations 3. The attempt at a solution Isn't this just theta = sin^-1 * (1.33/1.5) = 62.46 degrees but thats not right. And I probably need to do something with the 1 cm thick layer of water but I don't know what?