Question

In Fraunhoffer diffraction pattern due to a single slit, the slit of width 0.1 mm is illuminated by monochromatic light of wavelength 600 nm. What is the ratio of separation between the central maximum and first secondary minimum to the distance between screen and the slit?

• A. $6\times {10}^{-3}$m
• B. 0.1 m
• C. 6 m
• D. 100 m

Answer 1

The correct option is A $6\times {10}^{-3}$m

$tan\theta =\frac{\text{y}}{\text{D}}conditionfor1stminimaisasin\theta =\lambda sin\theta =\frac{\lambda }{a}\therefore \frac{y}{D}=\frac{\lambda }{a}=\frac{600\times {10}^{-9}}{0.1\times {10}^{-3}}=6\times {10}^{-3}m$