Interference pattern, wavelength

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The discussion centers on calculating the wavelength of monochromatic light from an interference pattern created by two slits separated by 127 µm, with a screen distance of 1.14 m. The user initially calculated the angle using the formula θ = arctan(y/L) and attempted to find the wavelength using m = 2, mistakenly interpreting m as the number of slits. It is clarified that m represents the order of the interference fringes, starting from m=0 for the central bright fringe. The correct approach involves using the appropriate value for m based on the observed fringe order. Accurate calculation of the wavelength requires proper identification of the fringe order.
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Homework Statement


Suppose the interference pattern shown in the figure is produced by monochromatic light passing through two slits, with a separation of 127 µm, and onto a screen 1.14 m away. What is the wavelength?
28-34.gif



Homework Equations


wavelength = (dsin\theta) / m
y=Ltan\theta


The Attempt at a Solution


\theta= arctan (y/L) = arctan (.023 / 1.4) = .941
then plugged it into get wavelenth. i used m = 2 for 2 slits
wavelenth = 127 x 10^-6m x sin .941 / 2

i think I have m wrong?
 
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i used m = 2 for 2 slits
m is not the number of slits. It is the order of the fringes starting from m=0 for the central bright fringe.
 

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