In a Young?s double-slit experiment, a set of parallel slits with a separation o
ID: 1380189 • Letter: I
Question
In a Young?s double-slit experiment, a set of parallel slits with a separation of 0.122 mm is illuminated by light having a wavelength of 590 nm and the interference pattern observed on a screen 4.50 m from the slits. (a) What is the difference in path lengths from the two slits to the location of a third order bright fringe on the screen? 1.770 mu m (b) What is the difference in path lengths from the two slits to the location of the third dark fringe on the screen, away from the center of the pattern? -2.065 The response you submitted has the wrong sign. Mu mExplanation / Answer
Path difference for Bright fringe = m x wavelength
where m = order of fringe
3rd order fringe
PAth difference = 3 x 590 x 10^-9 = 1.77 ?m
Path difference for Dark fringe = (m+0.5) x wavelength
where m = order of fringe - 1
PAth difference = (2+0.5) x 590 x 10^-9 = 1.475 ?m
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Answer
a) 1.77 ?m
b) 1.475 ?m