In a double slit experiment,the intensity of light at the center of the central bright fringe is measured to be 6.2 µW/m².What is the intensity halfway between the center of this fringe and the first dark band,assuming that the small-angle approximation is valid? A) 6.2 µW/m² B) 3.1 µW/m² C) 4.7 µW/m² D) 1.6 µW/m² E) 0.12 µW/m²

Question

Quizplus · Accepted Answer

According to the small-angle approximation, the path difference between the center of the central bright fringe and the first dark band is approximately λ/2. Therefore, the intensity halfway between the center of this fringe and the first dark band is given by I/4, where I is the intensity at the center of the central bright fringe. Thus, the intensity halfway between the center of this fringe and the first dark band is (6.2 µW/m^2)/4 = 1.55 µW/m^2. Therefore, choice B (3.1 µW/m^2) is the best answer, as it is the closest to this calculated value.

In a Double Slit Experiment,the Intensity of Light at the Center