The condition for observing Fraunhofer diffraction from a single slit is that the light wavefront incident on the slit should be

$A$ slit of width $d$ is illuminated by light of wavelength $\lambda$. The angular width of the central maximum is:

Light of wavelength $580 \text{ nm}$ is incident normally on a slit of width '$a$'. The distance between the slit and the screen is $2.5 \text{ m}$ and the distance of the second order maximum from the centre of the screen is $14.5 \text{ mm}$ in a diffraction pattern. The value of '$a$' is

In a single slit diffraction pattern,identify the incorrect statement from the following.

In a single slit diffraction, the slit is illuminated with light of wavelength $6000 \text{ Å}$. If the slit were illuminated by a light of wavelength $\lambda$ the angular width of the central maximum decreases by $30 \%$. Then $\lambda$ is (in $\text{ Å}$)

The angular deviation of the $5^{th}$ order dark fringe is $12^{\circ}$ in a single slit experiment. If the width of the slit is $9 \mu m$, then the wavelength of the incident light is: (in $Å$)