Light of wavelength 640 nm in water illuminates a glass (n = 1.5) wedge submerged in water (n = 1.33). If the distance between successive bright fringes is 6mm.
Find a) the change in thickness of the glass between these fringes
and b) the angle of the wedge
The Attempt at a Solution
Since it's a bright fringe and n=1 to n=1.5 to n=1.33, it's constructive so 2t= (m+1/2)lambda/nfilm. WHen i plug in the values i get t=(m+1/2)(6.40X10^-7 m)/2(2.5) but i'm not sure how i can find m with the distance between the bright fringes (y=6X10^-3 m)...
And for the angle of the wedge i thought that it would be pi since n=1 to n=1.5 to n=1.33.