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Mr.Sure
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Single slit diffraction
Red light of wavelength 633nm from a helium-neon laser passes through a slit 0.390mm wide. The diffraction pattern is observed on a screen 3.00m away. Define the width of a bright fringe as the distance between the minima on either side.
What is the width of the central bright fringe?
What is the width of the first bright fringe on either side of the central one?
asin(θ)= (m+1/2)λ
I used the slit length, screen distance and wavelength to find the angle of the light.
θ = arcsin([itex]\frac{λ}{2a}[/itex])
Then I drew a triangle to find the length of the fringe.
tan(θ) = [itex]\frac{h}{3}[/itex]
h = 3tan(θ)
h = .0024m
I got .0024 for h but it is wrong.
Homework Statement
Red light of wavelength 633nm from a helium-neon laser passes through a slit 0.390mm wide. The diffraction pattern is observed on a screen 3.00m away. Define the width of a bright fringe as the distance between the minima on either side.
What is the width of the central bright fringe?
What is the width of the first bright fringe on either side of the central one?
Homework Equations
asin(θ)= (m+1/2)λ
The Attempt at a Solution
I used the slit length, screen distance and wavelength to find the angle of the light.
θ = arcsin([itex]\frac{λ}{2a}[/itex])
Then I drew a triangle to find the length of the fringe.
tan(θ) = [itex]\frac{h}{3}[/itex]
h = 3tan(θ)
h = .0024m
I got .0024 for h but it is wrong.
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