$A$ slit of width $a$ is illuminated by white light. For red light $(\lambda = 6500 \; \mathring{A})$,the first minima is obtained at $\theta = 30^\circ$. Then the value of $a$ will be

Orange light of wavelength $6000 \times 10^{-10} \ m$ illuminates a single slit of width $0.6 \times 10^{-4} \ m$. The maximum possible number of diffraction minima produced on both sides of the central maximum is $........$

In a single slit diffraction of light of wavelength $\lambda$ by a slit of width $e$,the size of the central maximum on a screen at a distance $b$ is

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 . . . . . . $\mu m$.

For Bragg's diffraction by a crystal to occur,the $X$-ray of wavelength $\lambda$ and interatomic distance $d$ must satisfy which condition?

$A$ parallel beam of monochromatic light of wavelength $600 \,nm$ passes through a single slit of $0.4 \,mm$ width. The angular divergence corresponding to the second-order minima would be $...... \times 10^{-3} \,rad$.