The Rydberg formula is formulated by the Swedish physicist Johannes Rydberg. The Rydberg Equation is used to describe the wavelengths of the spectral lines of many chemical elements in atomic physics. It is used to calculate the wavelength of the electromagnetic radiation that is emitted in vacuum (λvac) based on the Rydberg constant which is approximately equal to 1.097 x 10^7 m^-1 and the principal quantum numbers (n1 and n2) of the orbitals.