The structure of solid crystals is investigated by using

An $X$-ray tube produces a continuous spectrum of radiation with its shortest wavelength of $45 \times 10^{-2} \text{ Å}$. The maximum energy of a photon in the radiation in $eV$ is (in $27,500$). $(h = 6.62 \times 10^{-34} \text{ J-s}, c = 3 \times 10^8 \text{ m/s})$.

The $X-$rays produced in a Coolidge tube of potential difference $40 \ kV$ have a minimum wavelength of:

The intensity of $X$-rays from a Coolidge tube is plotted against wavelength as shown in the figure. The minimum wavelength found is ${\lambda _c}$ and the wavelength of the ${K_\alpha }$ line is ${\lambda _k}$. As the accelerating voltage is increased:

The wavelength of the most energetic $X$-ray emitted when a metal target is bombarded by $100 \text{ keV}$ electrons is approximately.......$ \mathring{A} $

The essential distinction between $X$-rays and $\gamma$-rays is that