The wavenumber associated with the maximum energy in the Balmer series will be......

Who modified Bohr's theory by introducing elliptical orbits for electron path?

Emission transitions in the Paschen series end at orbit $n=3$ and start from orbit $n$ and can be represented as $\nu = 3.29 \times 10^{15} \, Hz \left(\frac{1}{3^2} - \frac{1}{n^2}\right)$. Calculate the value of $n$ if the transition is observed at $1285 \, nm$. Find the region of the spectrum.

The ratio of the slopes of the $KE_{max}$ vs $v$ and $V_0$ vs $v$ curves in the photoelectric effect gives ($v$ is the frequency of incident radiation and $V_0$ is the stopping potential).

The radius of the first Bohr orbit for hydrogen is $0.53 \ \mathring{A}$. The radius of the third Bohr orbit would be .............. $\mathring{A}$.

The separation energy of the electron present in the shell $n = 3$ is $1.51 \ eV$. What is the energy in the first excited state? ............ $eV$