If the radius of electron in the excited state of $\mathrm{He}^{+}$is $0.4232 \mathrm{~nm}$, the energy of…
If the radius of electron in the excited state of $\mathrm{He}^{+}$is $0.4232 \mathrm{~nm}$, the energy of electron in that excited state in $\mathrm{J}$ is :
(The radius and energy of electron in the first orbit of hydrogen atom are $52.9 \mathrm{pm}$ and $-2.18 \times 10^{-18} \mathrm{~J}$ respectively)