JEE Main 2019 — Wave Optics Question with Solution
From: JEE Main 2019 (Online) 11th January Evening Slot
Question
In a double-slit experiment, green light (5303) falls on a double slit having a separation of 19.44 m and awidht of 4.05 m. The number of bright fringes between the first and the second diffraction minima is :
Choose an option
Show full solutionCorrect option: B
Correct answer
B05
Step-by-step explanation
For diffraction
location of 1st minima
y1 = = 0.2469 D
location of 2nd minima
y2 = = 0.4938 D
Now for interference
Path difference at P.
= 4.8
path difference at Q
= 9.6
So orders of maxima in between P & Q is 5, 6, 7, 8, 9
So 5 bright fringes all present between P & Q.
Practice this on the real CBT interface
Solve this JEE Main question (and the rest of the Wave Optics chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.
Solve interactively →About this question
This is a previous-year question from JEE Main 2019, covering the Wave Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.