$A$ diffraction pattern is obtained by making blue light incident on a narrow slit. If blue light is replaced by red light,then:

In an experiment,electrons are made to pass through a narrow slit of width $'d'$ comparable to their de-Broglie wavelength. They are detected on a screen at a distance $'D'$ from the slit (see figure). Which of the following graphs can be expected to represent the number of electrons $'N'$ detected as a function of the detector position $'y'$ ($y = 0$ corresponds to the middle of the slit)?

In deriving the single slit diffraction pattern,it is stated that the intensity is zero at angles of $\theta = n\lambda / a$,where $a$ is the slit width. Justify this by suitably dividing the slit to bring out the cancellation.

In a single slit diffraction pattern,the distance between the plane of the slit and the screen is $1.3 \ m$. The width of the slit is $0.65 \ mm$ and the second maximum is formed at a distance of $2.6 \ mm$ from the center of the screen. The wavelength of light used is: (in $Å$)

If the measured angular separation between the second minimum to the left of the central maximum and the third minimum to the right of the central maximum is $30^{\circ}$ in a single slit diffraction pattern recorded using $628 \ nm$ light,then the width of the slit is . . . . . . $\mu m$.

The diffraction fringes obtained by a single slit are of