What is the difference between soft and hard $X-$rays?

The intensity of the $X$-ray beam emitted in an $X$-ray tube is increased by........

How are $X$-rays produced in the laboratory?

Hard $X$-rays for the study of fractures in bones should have a minimum wavelength of $10^{-11} \, m$. The accelerating voltage for electrons in the $X$-ray machine should be:

$X$-rays are used for the structural analysis of crystals because:

What does the $K\alpha$ characteristic $X$-ray represent?