The shortest wavelength for the Lyman series is $912 \ \text{Å}$. The longest wavelength in the Paschen series is: (in $\text{Å}$)

The shortest wavelength in the Paschen series of the Hydrogen spectrum is (Rydberg constant of hydrogen $R_H = 1.097 \times 10^7 \ m^{-1}$). (in $nm$)

The energy levels of the hydrogen spectrum are shown in the figure. There are some transitions $A, B, C, D$ and $E$. Transitions $A, B$ and $C$ respectively represent:

How many spectral lines are obtained when an electron in the ground state of hydrogen is excited to the principal quantum number $n = 3$?

The wavelength of light for the least energetic photons emitted in the Lyman series of the hydrogen spectrum is nearly. [Take $hc = 1240 \text{ eV-nm}$, change in energy of the levels $= 10.2 \text{ eV}$] (in $\text{ nm}$)

The ratio of longest wavelengths of the spectral lines in the Lyman and Balmer series of hydrogen spectrum is