JEE Main 2020 — Wave Optics Question with Solution
From: JEE Main 2020 (Online) 2nd September Evening Slot
Question
In a Young’s double slit experiment, 16 fringes
are observed in a certain segment of the
screen when light of a wavelength 700 nm is
used. If the wavelength of light is changed to
400 nm, the number of fringes observed in the
same segment of the screen would be
Choose an option
Show full solutionCorrect option: A
Correct answer
A28
Step-by-step explanation
Let the length of segment is ""
Let N is the no. of fringes in "" and w is fringe width.
Nw =
N =
As in both cases segment length is same.
and
=
=
16 × 700 = N2 × 400
N2 = 28
Let N is the no. of fringes in "" and w is fringe width.
Nw =
N =
As in both cases segment length is same.
and
=
=
16 × 700 = N2 × 400
N2 = 28
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