What is the approximate wavelength range of X-rays?

In an $X$-rays tube, the intensity of the emitted $X$-rays beam is increased by

The ${K_\alpha }\;X$-rays arising from a cobalt ($z = 27$) target have a wavelength of $179\;pm.$ The ${K_\alpha }\;X$-rays arising from a nickel target ($z = 28$) is

The longest wavelength that can be analysed by a sodium chloride crystal of spacing $d = 2.82\;A^\circ$ in the second order is

In producing $X$-rays a beam of electrons accelerated by a potential difference $V$ is made to strike a metal target. For what value of $V,\;X$-rays will have the lowest wavelength of $0.3094\;\mathop A\limits^ \circ$

Let ${\lambda _\alpha },{\lambda _\beta }$ and ${{\lambda '}_\alpha }$ denote the wavelengths of the ${\rm{X}}$-rays of the ${K_\alpha },{K_\beta }$ and ${L_\alpha }$ lines in the characteristic ${\rm{X}}$-rays for a metal. Then

What is the approximate wavelength range of X-rays?

The binding energy of the innermost electron in tungsten is $40\;keV.$ To produce characteristic X-rays using a tungsten target in an $X$-rays tube the potential difference $V$ between the cathode and the anti-cathode should be

X-ray of wavelength $\lambda = 2\mathop A\limits^ \circ$ is emitted from the metal target. The potential difference applied across the cathode and the metal target is

For characteristic $X$-ray of some material

In an $X$-ray tube electrons bombarding the target produce $X$-rays of minimum wavelength $1\;\mathop A\limits^ \circ .$ What must be the energy of bombarding electrons