(IMAGE ATTACHED) Where would maximum constructive interference occur and why?

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As clearly seen, the areas of maximum destructive interference occur in an X-shape.

However, my question is where would maximum constructive interference occur? And, more importantly, wphy?

1 Answer

The very dark bands and white areas


Constructive is where a positive and positive or negative and negative meet. Assuming that black is positive and white is negative, they cancel out to be gray. But where black only meets black and where white only meets white, the interference is constructive. So just look at the most white or the most black areas.