What is the energy associated with the first orbit of $Li^{2+}$ $(R_{H} = 2.18 \times 10^{-18} \ J)$?

The hydrogen spectrum consists of several spectral lines in the Lyman series ($L_1, L_2, L_3 \ldots$; $L_1$ has the lowest energy among the Lyman series). Similarly, it consists of several spectral lines in the Balmer series ($B_1, B_2, B_3 \ldots$; $B_1$ has the lowest energy among the Balmer lines). The energy of $L_1$ is $x$ times the energy of $B_1$. The value of $x$ is . . . . . . $\times 10^{-1}$ (Nearest integer).

Which of the following was $NOT$ proposed by Rutherford in his atomic model?

The shortest wavelength of hydrogen atom in Lyman series is $\lambda$. The longest wavelength in Balmer series of $He^{+}$ is

The four lowest energy levels of the $H$ atom are shown in the figure. The number of emission lines will be ...... .

When an electron in a hydrogen spectrum transitions from the $7^{th}$ energy level to the $1^{st}$ energy level,what is the total number of spectral lines produced?