$X$-rays are:

The difference between soft and hard $X-$rays is due to their:

$X$-rays of wavelength $\lambda$ are reflected from parallel planes of atoms in a crystal with spacing $d$ between two planes,as shown in the figure. If the two reflected beams interfere constructively,then the condition for maxima will be (where $n$ is the order of the interference fringe):

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

The wavelength of the ${K_\alpha}$ line for an element of atomic number $29$ is $\lambda$. Then the wavelength of the ${K_\alpha}$ line for an element of atomic number $15$ is (Take Moseley's constant $b = 1$ for both elements).

$X$-rays,when incident on a metal,do which of the following?