In Fraunhofer diffraction pattern, slit width is 0.2 mm and screen is at 2 m away from the lens. If the distance between the first minimum on either side of the central maximum is 1 cm , the wavelength of light used is

Step-by-step solution

The wavelength is determined using the single-slit diffraction condition for the first minimum, given by a ₁ = For small angles, ₁ y₁ D leading to = a y₁ D Given the distance between the first minima on either side is y = 1 cm = 0.01 m, the distance from central maximum to first minimum is y₁ = y 2 = 0.005 m With slit width a = 0.2 mm = 0.2 10⁻³ m and screen distance D = 2 m, substitution yields = 0.2 10⁻³ 0.005 2 = 5 10⁻⁷ m Converting to Ångstroms, where 1 Å = 10⁻¹⁰ m, gives = 5 10⁻⁷ 10¹⁰ = 5000 Å which correspond