The wavelength of $X-$rays is

If the operating potential of an $X-$ray tube is $50 \text{ kV}$,the velocity of $X-$rays coming out of it is

The wavelength $\lambda$ of the ${K_{\alpha}}$ line of characteristic $X$-ray spectra varies with atomic number $Z$ approximately as:

The wavelength of an $X$-ray photon is $0.01 \ \mathring A$. Its momentum in $kg \ m/s$ is .........

The pressure inside an $X$-ray tube is approximately:

When cathode rays strike a metal target of high melting point with very high velocity,then