The shortest wavelength of the spectral line in the Brackett series is .......

When the electron in the hydrogen atom jumps from the $2^{nd}$ orbit to the $1^{st}$ orbit,the wavelength of the radiation emitted is $\lambda$. When the electron jumps from the $3^{rd}$ orbit to the $1^{st}$ orbit,the wavelength of the emitted radiation will be:

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

Which of the following statement$(s)$ is(are) correct about the spectrum of hydrogen atom?
$(A)$ The ratio of the longest wavelength to the shortest wavelength in Balmer series is $9/5$.
$(B)$ There is an overlap between the wavelength ranges of Balmer and Paschen series.
$(C)$ The wavelengths of Lyman series are given by $\lambda = \frac{\lambda_0}{1 - 1/m^2}$,where $\lambda_0$ is the shortest wavelength of Lyman series and $m$ is an integer.
$(D)$ The wavelength ranges of Lyman and Balmer series do not overlap.

What is the shortest wavelength present in the Paschen series of spectral lines (in $nm$)?

Find the maximum wavelength of the Brackett series for a hydrogen atom in $\mathring A$.