ExamBro
ExamBro
JEE Mains · Physics · STD 12 - 10. Wave optics

In a double slit experiment shown in figure, when light of wavelength \(400 \mathrm{~nm}\) is used, dark fringe is observed at \(P\). If \(D=0.2 \mathrm{~m}\). the minimum distance between the slits \(S_1\) and \(S_2\) is ____________ \(mm\).

  1. A \(0.26\)
  2. B \(0.20\)
  3. C \(0.54\)
  4. D \(45\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(0.20\)

Step-by-step Solution

Detailed explanation

Path difference for minima at \(\mathrm{P}\) \( 2 \sqrt{\mathrm{D}^2+\mathrm{d}^2}-2 \mathrm{D}=\frac{\lambda}{2} \) \( \therefore \sqrt{\mathrm{D}^2+\mathrm{d}^2}-\mathrm{D}=\frac{\lambda}{4} \) \( \therefore \sqrt{\mathrm{D}^2+\mathrm{d}^2}=\frac{\lambda}{4}+\mathrm{D} \)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app