Two separate sodium lamps light two pinholes. On the screen you see:
AColoured fringes
BCurved fringes
CNo fringes at all
DSharp fringes
Answer & Solution
Correct answer: C. No fringes at all
1. Independent lamps change phase abruptly and randomly.
2. Their intensities simply add.
3. So no fringes appear.
_Source: NCERT Class 12 Physics Part II, Chapter 10, Wave Optics._
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