What are the limitations (drawback or shortcomings) of Bohr's model of atom?

What is Rydberg formula? What is the value of Rydberg constant ? What is its significance?

Calculate the wavelength of the first and limiting spectral line in the Lymann series of hydrogen spectrum.

Calculate the wavenumber for the longest wavelength transition in the Balmer series of atomic hydrogen.

What transition in the hydrogen spectrum would have the same wavelength as the Balmer transition n = 4 to n = 2 of He⁺ spectrum?

Emission transitions in the Paschen series end at orbit n = 3 and start from orbit n and can be represented as
v = 3.29 x 10¹⁵ (Hz) [1/3²- l/n².]

Calculate the value of n if the transition is observed at 1285 nm. Find the region of the spectrum.

Calculate the wavelength for the emission transition if it starts from the orbit having radius 1.3225 nm and ends at 211.6 pm. Name the series to which this transition belongs and the region of the spectrum.