If $X$-rays are produced by bombarding electrons with an energy of $40 \ keV$ on a target,what will be the minimum wavelength (in $\mathring{A}$) of the $X$-rays produced?

The energy of $X$-rays with a wavelength of $1.65 \, \mathring{A}$ is ............. $keV$ (Given: $h = 6.6 \times 10^{-34} \, J \cdot s$,$c = 3 \times 10^{8} \, m/s$,$1 \, eV = 1.6 \times 10^{-19} \, J$). (in $.5$)

An $X$-ray beam of wavelength $1 \ \mathring A$ is incident on a crystal with a lattice spacing of $2.8 \ \mathring A$. Find the value of the Bragg angle in degrees for the first-order diffraction.

The minimum wavelength of $X$-rays produced by $20 \ kV$ electrons is nearly (in $Å$)

The wavelength of the most energetic $X$-rays emitted when a metal target is bombarded by $40 \ keV$ electrons is approximately .............. $\mathring{A}$.

If the energy of a $K$-shell electron is $-40000 \ eV$ and a potential of $60000 \ V$ is applied to a Coolidge tube,which of the following $X$-rays will be formed?