Mosley measured the frequency (f) of the characteristic X-rays from many metals of different atomic number (Z) and represented his results by a relation known as Mosley's law. This law is (a, b are constants)

• A

  $\mathrm{f}=\mathrm{a}{\left(\mathrm{Z}-\mathrm{b}\right)}^2$

• B

  $\mathrm{Z}=\mathrm{a}{\left(\mathrm{f}-\mathrm{b}\right)}^2$

• C

  ${\mathrm{f}}^2=\mathrm{a}\left(\mathrm{Z}-\mathrm{b}\right)$

• D

  $\mathrm{f}=\mathrm{a}{\left(\mathrm{Z}-\mathrm{b}\right)}^{1/2}$