The allowed energy levels of electrons in a Hydrogen atom are given by $E_n=-13.6 / n^2 \mathrm{eV}$. For electronic transition in Hydrogen atom, what is the maximum frequency of the emitted photon?
$\left(h=6.62 \times 10^{-34} \mathrm{Js} ; \mathrm{e}=1.6 \times 10^{-19} \mathrm{C}\right)$

• A

  $2.1 \times 10^6 \mathrm{GHz}$
• B

  $5.5 \times 10^6 \mathrm{GHz}$
• Correct answer
  C

  $3.3 \times 10^6 \mathrm{GHz}$
• D

  $1.7 \times 10^6 \mathrm{GHz}$

Hence, the correct answer is option: 'C'.