Young Double Slit Experiment.
Explanation
The portion of the wave front incident on the slit behaves like the source of secodary wavelets .The wavelets leaving the slits are coherent Superposition of these wavelets result into the series of bright and dark bands which are observed on the second screen places at some distance.
Codition for Maxima
(constructive Interference)
AB
BD=ABsinθ
BD=dsinθ ∵A→B=d
Path Difference=dsinθ → (i)
Path Difference=mλ → (ⅱ)
From eqation (i)and (ⅱ)......
dsinθ=mλ → (ⅱi)
Codition for Minima
(Destructive Interference)
Path Difference=dsinθ → (iv)
Path Difference=(m+1/2)λ→(v)
dsinθ =(m+ 1/2)λ →(ⅵ)
Position for Bright Fringes:-
In △POC
Y = tanθ
L
Y=Ltanθ
tanθ will change into sinθ
∵ tanθ ≈sinθ
Y=L sinθ
From equation (ⅱi)⇒sinθ =mλ
d
Y=Lmλ
d
Position forDarkness Fringes:-
Y=Lsinθ
From equation 6 ⇒sinθ(m+1/2)λ
d
Y=L(m+1/2)λ
d Answer
..........Long Complete...............
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