JEE Mains · Physics · STD 12 - Wave optics
- JEE Mains 2020
- Medium
- MCQ
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
Pick an option to check your answer.
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 \(2I.\)
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