In the hydrogen atom spectrum, let $E_1$ and $E_2$ be the energies for the transitions $n=2 \rightarrow n=1$ and $n=3 \rightarrow n=2$ respectively. The ratio $E_2 / E_1$ is

How much energy is needed to release the electron from the second excited state in the hydrogen atom (in $eV$)?

In a hydrogen atom,if the energy difference between the $n = 2$ and $n = 3$ orbits is $E$,how much energy (in terms of $E$) is required to remove an electron from the ground state?

An electron with kinetic energy $E$ collides with a hydrogen atom in the ground state. The collision will be elastic

An electron in a hydrogen atom first jumps from the third excited state to the second excited state and then from the second excited state to the first excited state. The ratio of the wavelengths $\lambda_1 : \lambda_2$ emitted in the two cases is

If the ionisation energy for the hydrogen atom is $13.6 \ eV$,then the energy required to excite it from the ground state to the next higher state is nearly: (in $eV$)