In a Young\'s double-slit experiment, two parallel slits with a slit separation
ID: 1520920 • Letter: I
Question
In a Young's double-slit experiment, two parallel slits with a slit separation of 0.130 mm are illuminated by light of wavelength 578 nm, and the interference pattern is observed on a screen located 3.65 m from the slits.
(a) What is the difference in path lengths from each of the slits to the location of the center of a second-order bright fringe on the screen?
µm
(b) What is the difference in path lengths from the two slits to the location of the center of the second dark fringe away from the center of the pattern?
µm
Explanation / Answer
Here,
wavelength = 578 nm
screen distance , D = 3.65 m
slit speration ,d = 0.130 mm
a)
difference in path at the location of second order fringe = 2 * wavelength
difference in path at the location of second order fringe = 2 * 0.578 um
difference in path at the location of second order fringe = 1.156 um
b)
for the second dark fringe
difference in path at the location of second order dark fringe = 1.5 * wavelength
difference in path at the location of second order dark fringe = 1.5 * 0.578 um
difference in path at the location of second order dark fringe = 0.867 um