The maximum number of emission lines for atomic hydrogen that you would expect to see with the naked eye if the only electronic levels involved are those shown in the figure,is

In the spectrum of a hydrogen atom,the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is

The number of spectral lines in a hydrogen atom is . . . . . . .

The transition from the state $n = 4$ to $n = 3$ in a hydrogen-like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from:

Hydrogen atoms are excited from the ground state to the principal quantum number $n = 5$. The number of spectral lines observed will be:

The wavelength of radiation emitted is $\lambda_0$ when an electron jumps from the second excited state to the first excited state of a hydrogen atom. If the electron jumps from the third excited state to the second orbit of the hydrogen atom,the wavelength of the radiation emitted will be $\frac{20}{x} \lambda_0$. The value of $x$ is