MCQ
If the path difference between the slits S1 and S2 is $\lambda$, the central fringe will have an intensity of:
- A0
- Ba2
- C2a2
- D4a2
✓
Answer
- 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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