What is the path difference for destructive interference?
The correct option is (d).
Explanation:
If the waves interfere destructively, then path difference is given by λ/2, 3λ/2, 5λ/2 etc.
Therefore, path difference of a destructive interference is (2n+1)λ/2 (where n = 0, 1, 2, 3, ...) etc.
