What is the thickness of the paper in this interference experiment?

AI Thread Summary
The problem involves calculating the thickness of a piece of paper placed at the end of a 4 cm long air wedge, where interference fringes are observed with light of wavelength 639 nm. A dark fringe is noted at both the wedge's vertex and the paper end, with 56 bright fringes in between. The formula used for the calculation is delta X = L (lambda / 2t), where t represents the thickness of the paper. After working through the calculations, the individual expresses relief at solving the problem, indicating a successful resolution. The discussion highlights the application of interference patterns in determining material thickness.
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Homework Statement



A piece of paper is placed at the end of an air wedge 4 cm long. Interference fringes appear when the light of wavelength 639 nm is reflected from the wedge. A dark fringe occurs at both the vertex of the wedge and at its paper end, and 56 bright fringes appear between. Calculate the thickness of the paper.

Homework Equations




delta X = L (lambda / 2t)

where t is the thickness of the paper
lambda = wavelength
l = length of air wedge
X = distance between fringes.
 
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nevermind i got it I am stupid :(
 

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