Question 358: Waves Optics

Question

A beam of light having wavelength $$5400 \mathrm{~A}$$ from a distant source falls on a single slit $$0.96 \mathrm{~mm}$$ wide and the resultant diffraction pattern is observed on a screen $$2 \mathrm{~m}$$ away. What is the distance between the first dark fringe on either side of central bright fringe?

Accepted Answer

Distance between the two dark fringes on either side of the central bright fringe is given by
$$2 \mathrm{x}=\frac{2 \lambda \mathrm{D}}{\mathrm{a}}$$
Putting $$\lambda=5.4 	imes 10^{-7} \mathrm{~m}, \mathrm{D}=2 \mathrm{~m}$$ and $$\mathrm{a}=0.9 	imes 10^{-3} \mathrm{~m}$$ we get $$2 x=2.4 \mathrm{~mm}$$

Answer

4.8 mm

Answer

1.2 mm

Answer

2.4 mm

Answer

3.6 mm

Waves Optics

A beam of light having wavelength $5400 \mathrm{~A} from a distant source falls on a single slit 0.96 \mathrm{~mm} wide and the resultant diffraction pattern is observed on a screen 2 \mathrm{~m}$ away. What is the distance between the first dark fringe on either side of central bright fringe?

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