Physics · Atomic Physics

In a normal Zeeman effect experiment, the spectral splitting of a line at wavelength 643.8 nm (corresponding to the transition 5 1D2 → 5 1P1 of cadmium atoms) is observed. If the spectrometer has a resolution of 0.01 nm, what is the minimum magnetic field needed to resolve this splitting? (Given: me = 9.1 × 10-31 kg, e = 1.6 × 10-19 C, and c = 3 × 108 m/s)