In a single slit diffraction experiment, the diffraction pattern is observed on a screen placed at a distance of 2m from the slit of 1mm width. If the distance between the first dark fringe on either side of the central to right fringe is 2.2 mm. what is the wave length of the monochromatic light from a distance source, used in this experiment?

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.