MCQ
If the path difference between the slits S1​ and S2​ is $\lambda$, the central fringe will have an intensity of:
  • A
    0
  • B
    a2
  • C
    2a2
  • D
    4a2

Answer

  1. 0

Explanation:

Path difference at the central fringe will be the same as the path difference at the slits i.e. $\lambda$.

Hence, the waves reaching the central fringe will be 180° out of phase and will result in destructive interference. Hence, the intensity of the central fringe will be 0.

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