Bohr’s theory successfully explains the hydrogen spectrum. It also explains the spectrum of some other one-electron system (H-like system) such as He⁺, Li²⁺, Be³⁺ etc. With the help of Bohr’s theory we find out, Radius of the orbit in which the electron is revolving around the nucleus, Energy of electron in an orbits, velocity and wavelength.

Column - I		Column - II		Column - III
(I)	Radius	(i)	$\frac{2\pi {\mathrm{Ze}}^2}{\mathrm{nh}}$	(P)	$-\frac{{\mathrm{Z}}^2}{{\mathrm{n}}^2}\times 313.6$
(II)	Velocity	(ii)	$\frac{n^2{h}^2}{4{\pi }^{2}mZ{e}^2}$	(Q)	$\mathrm{R}\times {\mathrm{Z}}^2\left[\frac{1}{{\mathrm{n}}_1^2}-\frac{1}{{\mathrm{n}}_2^2}\right]$
(III)	Energy	(iii)	$\frac{2{\pi }^2{\mathrm{me}}^4}{{\mathrm{ch}}^2}$	(R)	${\left(\frac{{\mathrm{Ze}}^2}{\mathrm{rm}}\right)}^{1/2}$
(IV)	Wavelenth	(iv)	$-\frac{2{\pi }^2\mathrm{m}{Z}^2{\mathrm{e}}^4}{{\mathrm{n}}^2{\mathrm{h}}^2}$	(S)	$\frac{{\mathrm{n}}^2}{\mathrm{Z}}\times 0.0529$