For Fraunhofer diffraction to occur:

$A$ plane wavefront of wavelength $6000 \, \mathring A$ is incident on a slit of width $0.2 \, mm$. $A$ Fraunhofer diffraction pattern is obtained on a screen at a distance of $2 \, m$ from the slit. What is the width of the central maximum in $mm$?

$A$ Fraunhofer diffraction pattern due to a narrow slit is obtained on a screen placed at a distance $D$ from the slit whose slit width is $a$. The distance of the first secondary maximum from the central maximum is

Find the correct condition$(s)$ for Fraunhofer diffraction due to a single slit.

In a Fraunhofer diffraction,light of wavelength $\lambda$ is incident on a slit of width $d$. The diffraction pattern is observed on a screen placed at a distance $D$. If the linear width of the central maximum is equal to two times the width of the slit,then the value of $D$ is:

The angular separation of the central maximum in the Fraunhofer diffraction pattern is measured. The slit is illuminated by light of wavelength $6000 Å$. If the slit is illuminated by light of another wavelength,the angular separation decreases by $20 \%$. The wavelength of light used is (in $Å$)