Question 418: Wave Optics

Question

For a parallel beam of monochromatic light of wavelength '$$\lambda $$' , diffraction is produced by a single slit whose width 'a' is of the order of the wavelength of the light. If 'D' is the distance of the screen from the slit, the wifth of the central maxima will be

Accepted Answer

For central maxima, sin $$	heta $$ = $${\lambda  \over a}$$
Also, $$	heta $$ is very-very small so
sin $$	heta $$ $$ \approx $$ tan$$	heta $$ = $${y \over D}$$
$$ 	herefore $$ $${y \over D}$$ = $${\lambda  \over a}$$
$$ \Rightarrow $$ y = $${{\lambda D} \over a}$$
Width of central maxima = 2y = $${{2D\lambda } \over a}$$

Answer

$${{Da} \over \lambda }$$

Answer

$${{2Da} \over \lambda }$$

Answer

$${{2D\lambda } \over a}$$

Answer

$${{D\lambda } \over a}$$

Wave Optics

For a parallel beam of monochromatic light of wavelength '$\lambda $' , diffraction is produced by a single slit whose width 'a' is of the order of the wavelength of the light. If 'D' is the distance of the screen from the slit, the wifth of the central maxima will be

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