1. The problem statement, all variables and given/known data If we shine white light on an air wedge like that shown in the figure below, the colors that are weak in the light reflected from any point along the wedge are strong in the light transmitted through the wedge. Explain why this should be so. http://www.practicalphysics.org/imageLibrary/jpeg350/128.jpg [Broken] 2. Relevant equations Constructive reflection from thin film, no relative phase shift 2t = m*lambda (m = 0,1,2...) Destructive reflection from thin film, no relative phase shift 2t = (m + 0.5)lambda (m = 0,1,2...) 3. The attempt at a solution Since the light is passing through the wedge has a greater index of refraction, that means that the light wave actually slows down as it passes through. In waves, v = f * lambda so we can find the relationship between the constructive interference and the velocity of the wave by (d/t) = f * lambda t = d / (f * lambda) 2(d / f * lambda) = m lambda 2d/f = m. And I'm completely stuck here. I think I'm going in a wrong direction to answer this problem. Can anyone help me?