Question

The first diffraction minimum due to single slit diffraction is $\theta ,$ for a light of wavelength $5000A.$ If the width of the sit is $1\times {10}^{-4},$ then the value of $\theta$ is

• A. ${30}^0$
• B. ${45}^0$
• C. ${60}^0$
• D. ${15}^0$

Answer 1

The correct option is A ${30}^0$

$\begin{array}{c}d\sin \theta =n\lambda ,n=1\\ 1\times {10}^{-6}\times \sin \theta =5000\times {10}^{-10}\\ \sin \theta =\frac{1}{2}\\ \theta =30\end{array}$