The half angular width of the central maxima in the Fraunhofer diffraction due to a slit of width $\frac{1200}{\sqrt{2}} \ \mu m$ is $45^o$. Then the wavelength of the light is ...... $\mu m$.

In a single slit diffraction pattern, the distance between the first minimum on the left and the first minimum on the right is $5 \,mm$. The screen on which the diffraction pattern is obtained is at a distance of $80 \,cm$ from the slit. The wavelength used is $6000 \mathring{A}$. The width of the slit is (in $\,mm$)

$A$ parallel beam of fast-moving electrons is incident normally on a narrow slit. $A$ screen is placed at a large distance from the slit. If the speed of the electrons is increased,which of the following statements is $CORRECT$?

In the diffraction pattern, the first maximum is at $30^{\circ}$, when a monochromatic light of wavelength $\lambda$ is incident on a slit of width $a$. For the same wavelength, if the slit width is changed, so that the first maximum is at $45^{\circ}$, by how much is the slit width changed?

$A$ diffraction pattern is obtained using a beam of red light. If red light is replaced by blue light,then:

$A$ slit of size $0.15 \ cm$ is placed at $2.1 \ m$ from a screen. On illuminating it by a light of wavelength $5 \times 10^{-5} \ cm$,the width of the central maxima will be: