In the graph between $\sqrt{\mathrm{\nu }}$ and Z for the Moseley' equation, $\sqrt{\mathrm{\nu }}=\mathrm{a}\left(\mathrm{Z}-\mathrm{b}\right)$ , the intercept $\mathrm{OX}$ is $1$ on $\sqrt{\mathrm{\nu }}$ axis.



What is the frequency $\mathrm{\nu }$, when the atomic number $\mathrm{Z}$ is $52$?

Identify the incorrect match.

It is observed that characteristic X-ray spectra of elements show regularity. When frequency to the power 'n' i.e. ${\mathrm{v}}^{\mathrm{n}}$ of X-rays emitted is plotted against atomic number $\mathrm{Z}$, the following graph is obtained.

The value of 'n' is