When light is incident on a diffraction grating,the zero-order principal maximum will be:

In an experiment,electrons are passed through a narrow slit of width $d$ equal to their de Broglie wavelength. They are detected on a screen at a distance $D$ from the slit. Which of the following graphs represents the number of electrons $N$ detected as a function of the detector position $y$ ($y = 0$ corresponds to the middle of the slit)?

Light of wavelength $\lambda = 5000 \ \mathring{A}$ falls normally on a narrow slit. $A$ screen is placed at a distance of $1 \ m$ from the slit and perpendicular to the direction of light. The first minima of the diffraction pattern is situated at $5 \ mm$ from the centre of the central maximum. The width of the slit is ....... $mm$.

In a single slit diffraction experiment, a parallel beam of green light of wavelength $\lambda = 550 \,nm$ passes through a slit of width $a = 0.20 \,mm$. The transmitted light is collected on a screen at a distance $D = 100 \,cm$ away. The distance of the first-order minima from the central maximum is $x \times 10^{-5} \,m$. The value of $x$ is:

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

$A$ slit of size '$a$' is illuminated by a parallel beam of light of wavelength $\lambda$. The angle at which this light is diffracted is approximately . . . . . . .