Wavelength of radiation corresponding to this energy,
\(\lambda=\frac{h c}{E}=\frac{12400 \mathrm{eVA}}{2 \mathrm{eV}}=6200 \mathrm{A}\)
The frequency of this radiation
\(=\frac{c}{\lambda}=\frac{3 \times 10^{8} \mathrm{m} / \mathrm{s}}{6200 \times 10^{-10} \mathrm{m} / \mathrm{s}}\)
\(\Rightarrow v=5 \times 10^{14} \mathrm{Hz}\)