Question

First bright fringe First dark spot ITIN Central bright band < Kirst dark spot first bright fringe 1.) A single slit of width W = 0.11 mm is illuminated by light of wavelength, 2 = 620 nm (see figure). a) Calculate the angle (@) at which the ray in the figure is pointing. b) Calculate the size (width along the screen) of the central bright band if the screen is located 2.30 m away from the slit.

Answer 1

slit width, W=0-11mm -0.11x10-3m first bright bringe a first dark spot t Central bright bond Jo ITON wavelength of light, x = 620nm -620 x 10-9m (a) By the formula, wsmo ma where mzorder no = 3 Chere from the fig) ma 3x620810-9m Ooll x 10-3 m or simom o=0.970 ExAns. (b) distance of screen from the slit is L=2.30m het central width is D. The width of the central maximum can be derived the separation between the first minimum either side of the central mooimum. So By the formula, De ont a 222 = 2 X AL W - 2x 620 x 10-9 mx 2.30 m 0.11 x 10-3 m D = 0.026 m Or D = 2.6cm Ir Aus