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Question
In Young’s experiment interference bands were produced on a screen placed at 150 cm from two slits, 0.15 mm apart and illuminated by the light of wavelength 6500 Å. Calculate the fringe width.
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Solution
Given:
D = 150 cm = 1.5 m,
d = 0.15 mm = 1.5 x 10-4 m,
λ = 6500 Å = 6.5 x 10-7 m
To find:
Fringe width ( X )
Formula:
X = `"λD"/"d"`
Calculation:
From formula,
X = `[6.5 xx 10^-7 xx 1.5]/[1.5 xx 10^4]`
X = 6.5 x 10-3 m
X = 6.5 mm
The fringe width is 6.5 mm
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