A beam of light is sent directly down onto a glass plate (n = 1.5) and a plastic plate (n = 1.2) that form a thin wedge of air (see the drawing). An observer looking down through the glass plate sees the fringe pattern shown in the lower part of the drawing, with the dark fringes at the ends A and B. The wavelength of the light is 520 nm. Using the fringe pattern shown in the drawing, determine the thickness of the air wedge at B.

Transcribed Image Text:

Thin wedge of air Glass n 1.5 Plastic n 1.2