A beam of light of wavelength 600 ~nm from a source falls on a single slit 1 ~mm wide and the resulting diffraction pattern is observed on a screen 2 ~m away. The distance between the first dark fringes on either side of the central bright fringe is

Step-by-step solution

Given =600 ~nm =600 10⁻⁹ ~m D=2 ~m , d=1 ~mm =1 10⁻³ ~m The distance of first dark fringe from central bright fringe, aligned y &= D d &= 2 600 10⁻⁹ 1 10⁻³ =1.2 ~mm aligned Distance between first dark fringe on either side of central bright fringe =2 y=1.2 2=2.4 ~mm