Question

Monochromatic light of wavelength $4500\mathring{A}$ falls on slit of width ${}^{\prime }{a}^{\prime }.$ In diffraction pattern second maxima deviates through ${30}^{}$. The slit width is ___________ .

Answer 1

Given,

Wavelength, $\lambda =4500\times {10}^{-10}m$

In difdfraction pattern second maxima

$a\sin \theta =2\lambda$ ,a is the slit width

$a\sin 30=2\times 4500\times {10}^{-9}$

$a=18000\times {10}^{-9}$

$a=0.18\times {10}^{-4}m$