question_answer

State with reason, how would the linear width of central maximum change if (i) monochromatic yellow light is replaced with red light, and (ii) distance between the slit and the screen is increased.     

Answer:

                The linear width of central bright maximum is given by                 \[{{\beta }_{0}}=\frac{2D\lambda }{d}\] (i) If monochromatic yellow light is replaced with red light, the linear width of the central maximum increases because\[{{\lambda }_{red}}>{{\lambda }_{yellow}}\]. (ii) If the distance (D) between the slit and the screen is increased, the linear width of the central maximum increases.