Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
In Young's double slit experiment the separation between the slits is doubled without changing other setting of the experiment to obtain same fringe width, the distance ' $\mathrm{D}$ ' of the screen from slit should be made
PhysicsWave OpticsMHT CETMHT CET 2023 (10 May Shift 1)
Options:
  • A $\frac{D}{2}$
  • B $\frac{\mathrm{D}}{\sqrt{2}}$
  • C $2 \mathrm{D}$
  • D $4 \mathrm{D}$
Solution:
2306 Upvotes Verified Answer
The correct answer is: $2 \mathrm{D}$
Fringe width,
$\mathrm{W}=\frac{\lambda \mathrm{D}}{\mathrm{d}}$
Given: $\mathrm{d}=2 \mathrm{~d}$
$\Rightarrow \mathrm{W}^{\prime}=\frac{\lambda \mathrm{D}^{\prime}}{2 \mathrm{~d}}$
Since given,
$\begin{aligned}
& \mathrm{W}=\mathrm{W}^{\prime} \\
\therefore & \frac{\lambda \mathrm{D}}{\mathrm{d}}=\frac{\lambda \mathrm{D}^{\prime}}{2 \mathrm{~d}} \\
\therefore & \mathrm{D}^{\prime}=2 \mathrm{D}
\end{aligned}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.