1. The two prominent yellow lines in the spectrum of sodium result from transitions to the ground state from the 3p state with the electron spin-up, and from the 3p state with the electron spin-down. The wavelengths these two lines are 589.0 nm and 589.6 nm. (a) Calculate the energies in eV of the photons corresponding to these wavelengths, and the difference in energy of these photons AE. (b) The energy difference you found in part (a) is due to the spin-orbit effect. An electron in the 3p state of sodium experiences an internal magnetic field B, due to the orbital angular momentum. For a magnetic field B₁, the spin-orbit energy splitting is AE = 2µBB₁, where B is the Bohr magneton. Find the orbital magnetic field By from the energy difference AE you found in part (a).

1. The two prominent yellow lines in the spectrum of sodium result from transitions to the ground state from the 3p state with the electron spin-up, and from the 3p state with the electron spin-down. The wavelengths these two lines are 589.0 nm and 589.6 nm. (a) Calculate the energies in eV of the photons corresponding to these wavelengths, and the difference in energy of these photons AE. (b) The energy difference you found in part (a) is due to the spin-orbit effect. An electron in the 3p state of sodium experiences an internal magnetic field B, due to the orbital angular momentum. For a magnetic field B₁, the spin-orbit energy splitting is AE = 2µBB₁, where B is the Bohr magneton. Find the orbital magnetic field By from the energy difference AE you found in part (a).