The wavelengths of $K_\alpha$ lines of two elements are $250 \, pm$ and $179 \, pm$, respectively. The number of elements between these two elements in the periodic table will be:

The wavelength of the most energetic $X$-rays emitted when a metal target is bombarded by $40 \ keV$ electrons is approximately ....... $\mathring{A}$. $(h = 6.62 \times 10^{-34} \ J \cdot s; 1 \ eV = 1.6 \times 10^{-19} \ J; c = 3 \times 10^8 \ m/s)$

Consider the following two statements $A$ and $B$ and identify the correct choice in the given answer.
$A:$ The characteristic $X-$ray spectrum depends on the nature of the material of the target.
$B:$ The short wavelength limit of the continuous $X-$ray spectrum varies inversely with the potential difference applied to the $X-$ray tube.

The emission of continuous $X$-rays is due to:

When cathode rays (tube voltage $\sim 10 \ kV$) collide with the anode of high atomic weight,then we get:

The wavelength of the $K_{\alpha}$ line for an element with atomic number $57$ is $\lambda$. What will be the wavelength of the $K_{\alpha}$ line for an element with atomic number $29$?