JEE Main 2019 — Wave Optics Question with Solution
From: JEE Main 2019 (Online) 12th April Morning Slot
Question
In a double slit experiment, when a thin film of thickness t having refractive index . is introduced in front of
one of the slits, the maximum at the centre of the fringe pattern shifts by one fringe width. The value of t is
( is the wavelength of the light used) :
Choose an option
Show full solutionCorrect option: D
Correct answer
D
Step-by-step explanation
As we know,
Path difference introduced by thin film,
.......(i)
and if fringe pattern shifts by one frings width, then path difference,
.......(ii)
So, from Eqs. (i) and (ii), we get
.......(i)
and if fringe pattern shifts by one frings width, then path difference,
.......(ii)
So, from Eqs. (i) and (ii), we get
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