Question

A wedge if formed with two thin 20cm pieces of glass. The wedge is 8μm at its thickest point. The wedge is filled with a liquid with index of refraction n = 1.33.

a) When viewed in transmission whats the distance between the corner and the m=7 max

b) whats the distances between 2 consecutive bright fringes viewed in reflection

c) In the corner likely to be a bright or dark fringe when viewed in transmission

d) Draw a diagram showing the phase states for each ray in transmission and reflection

(Comment asking for diagram it is just two pieces of glass put in a 'V' wedge formation and none is actually given on the question and I do not think it is needed)

Answer 1

In aV shaped wedge the fringes are produced due to the interference of reflected ray from the top surface and the reflected ray from the second surface which undergoes e diffraction from the top surface.The interfering rays do not enter the eyes parallel to each other but they appear to diverge from a point near the film.