Physics - Modern Physics Question with Solution | TestHub

The ratio of wavelengths for transition of electrons from $2^{\text{nd }}$ orbit to $1^{\text{st }}$ orbit of Helium $\left({\mathrm{He}}^{++}\right)$and Lithium $\left({\mathrm{Li}}^{++}\right)$is (Atomic number of Helium $=2$, Atomic number of Lithium = 3)