A soap film (n= 1.33) is contained within a rectangular wire frame. The frame is held veritcally so that the film drains downward and forms a wedge with flat faces. The thickness of the film at the top is essentially zero. The film is viewed by reflected white light with near-normal incidence, and the first violet ( Wavelength= 420nm) interference band is observed 3.00cm from the top edge of the film.
a) Locate the first red (wavelength= 680nm) interference band.
b) Determine the film thickness at the postitions of the violet and red bands.
c) What is the wedge angle of the film?