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

$X$-rays will travel the minimum distance in which of the following materials?

The wavelength of an $X$-ray beam is $10 \, \mathring{A}$. The mass of a fictitious particle having the same energy as that of the $X$-ray photons is $\frac{x}{3} h \, \text{kg}$. The value of $x$ is ....... . ($h =$ Planck's constant)

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

In vacuum,an electron of energy $10 \ keV$ hits a tungsten target. The emitted radiation will be:

If the wavelength of the $K_\alpha$ line of Molybdenum (atomic number $Z = 42$) is $0.7078\, \mathring A$,then the wavelength of the $K_\alpha$ line of Zinc (atomic number $Z = 30$) is .......