A single slit of width $0.04,\text{mm}$ is illuminated by monochromatic light of wavelength $600,\text{nm}$. A screen is placed $2.0,\text{m}$ behind the slit. Determine the linear width of the central bright fringe on the screen.

Step-by-step solution

1. $w=\frac{2lambdaL}{a}$ is the formula for the width of the central maximum.
2. $a=0.04,\text{mm}=4.0\times 10^{-5},\text{m}$, $\lambda =600,\text{nm}=6.0\times 10^{-7},\text{m}$, $L=2.0,\text{m}$.
3. $w=\frac{2(6.0\times 10^{-7},\text{m})(2.0,\text{m})}{4.0\times 10^{-5},\text{m}}$
4. $w=\frac{2.4\times 10^{-6},\text{m}}{4.0\times 10^{-5},\text{m}}=6.0\times 10^{-2},\text{m}$
5. $6.0\times 10^{-2},\text{m}=6.0\times 10^1,\text{cm}$

Concept tested: Diffraction by single slit

Published 16 September 2026 · How this solution was prepared and checked