1. The problem statement, all variables and given/known data A sheet of glass (nglass = 1.5) is coated with a 95.6-nm-thick layer of magnesium fluoride (ncoating = 1.38) to prevent reflection in the visible spectrum. Assume the incoming light is normal to the surface. What is the longest wavelength of light strongly reflected from this coated surface? 2. Relevant equations 3. The attempt at a solution 95.6 = x/4(1.38) = 527 nm This is incorrect however.