The limiting line in the Balmer series of the $H$ spectrum has a frequency of ....... $(R_\infty = 3.29 \times 10^{15} \, cycles/s)$

The Balmer series in the hydrogen spectrum corresponds to the transition from $n_1 = 2$ to $n_2 = 3, 4, ...$ This series lies in the visible region. Calculate the wave number of the line associated with the transition in the Balmer series when the electron moves to the $n = 4$ orbit. $(R_H = 109677 \ cm^{-1})$

Energy and radius of the first Bohr orbit of $He^{+}$ and $Li^{2+}$ are: $[$Given $R_{H} = 2.18 \times 10^{-18} \ J, a_{0} = 52.9 \ pm$ $]$

According to Bohr's principle,the relation between principal quantum number $(n)$ and the radius of the orbit $(r)$ is:

From the following energy levels of a hydrogen atom,the values of $E_{\infty}$ and $E_3$ in $J$ are,respectively: $E_{\infty} = \ldots \ldots \ldots$ $E_3 = \ldots \ldots \ldots$ Given: $E_2 = -0.545 \times 10^{-18} \ J$,$E_1 = -2.18 \times 10^{-18} \ J$.

What is the numerical value of angular momentum for an electron in the first orbit of a hydrogen atom? $(h = 6.626 \times 10^{-34} \ J \ s)$