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

Figure here shows \(P\) and \(Q\) as two equally intense coherent sources emitting radiations of wavelength \(20 \,m\). The separation \(PQ\) is \(5.0 \,m\) and phase of \(P\) is ahead of the phase of \(Q\) by \(90^{0}\). \(A, B \) and \( C\) are three distant points of observation equidistant from the mid-point of \(PQ\). The intensity of radiations at \(A, B, C\)  will bear the ratio

  1. A \(0 : 1 : 4\)
  2. B \(4 : 1 : 0\)
  3. C \(0 : 1 : 2\)
  4. D \(2 : 1 : 0\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(2 : 1 : 0\)

Step-by-step Solution

Detailed explanation

Since \(P\) is ahead of \(Q\) by \(90^\circ\) and path difference between \(P\) and \(Q\) is \(\lambda /4.\)Therefore at \(A\), phase difference is zero, so intensity is \(4I\). At \(C \) it is zero and at \(B\), the phase difference is \(90^\circ\), so intensity is \(2I.\)
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app