hree spectral lines, however the angular momenta involved.) netic lec- ) as tan- SECTION 9.5 (Spin Magnetic Moments) 9.18 The electron's total magnetic moment is given by (9.25). (a) What are the possible values of for an electron with/ = 0? (b) Compare these with the values of u for a hypothe tical spinless electron with / 1. a p e to )? SECTION 9.6 (The Anomalous Zeeman Effect) 9.19 Consider a hydrogen atom in its ground level, placed in a magnetic field of 0.7 T along the z axis. (a) What is the energy difference between the spin-up and spin-down states? (b) An experimenter wants to excite the atom from the lower to the upper state by sending in photons of the appropriate energy. What energy is this? What is the wavelength? What kind of radiation is this? (Visible? UV? etc.) nd e. e e Consider a hydrogen atom in the 3d state with itc eneroy 9.20 should be a magnetic moment with the general form (9.23) and that the spin gyromagnetic ratio does not necessarily have the same value as the orbital ratio e/2me are both correct. Experiment shows that there is a magnetic mo- ment with the form (9.23) and that the spin gyromagnetic ratio y is e me, just wice the value of the orbital ratio, e/2me; that is, Section 9.6 The Anomalous Zeeman Effect 297 George Uhlenbeck and Samuel Goudsmit (1900-1988, Dutch, American) (1902-1978, Dutch, American) e s Pl spin (9.24) me The total magnetic moment of any electron is just the sum of its orbital and spin moments e (L+ 2S) 2me porb+ spin (9.25) ltot As we describe in the next two sections, much of the evidence for the elec- tron's spin comes from the repeated success of the formula (9.25) in explaining a wide variety of experimental results. The suggestion that the electron has a spin angular momentum and a Uhlenbeck (center) and Goudsmit (right) are shown here with col- league Oskar Klein (left). In 1925 Goudsmit and Uhlenbeck, while both graduate students at Leiden, showed that several puzzles in inined nding magnetic moment given, as we now know, by (9.24)] is gener- el Goudsmit and George Uhlenbeck corre

hree spectral lines, however the angular momenta involved.) netic lec- ) as tan- SECTION 9.5 (Spin Magnetic Moments) 9.18 The electron's total magnetic moment is given by (9.25). (a) What are the possible values of for an electron with/ = 0? (b) Compare these with the values of u for a hypothe tical spinless electron with / 1. a p e to )? SECTION 9.6 (The Anomalous Zeeman Effect) 9.19 Consider a hydrogen atom in its ground level, placed in a magnetic field of 0.7 T along the z axis. (a) What is the energy difference between the spin-up and spin-down states? (b) An experimenter wants to excite the atom from the lower to the upper state by sending in photons of the appropriate energy. What energy is this? What is the wavelength? What kind of radiation is this? (Visible? UV? etc.) nd e. e e Consider a hydrogen atom in the 3d state with itc eneroy 9.20 should be a magnetic moment with the general form (9.23) and that the spin gyromagnetic ratio does not necessarily have the same value as the orbital ratio e/2me are both correct. Experiment shows that there is a magnetic mo- ment with the form (9.23) and that the spin gyromagnetic ratio y is e me, just wice the value of the orbital ratio, e/2me; that is, Section 9.6 The Anomalous Zeeman Effect 297 George Uhlenbeck and Samuel Goudsmit (1900-1988, Dutch, American) (1902-1978, Dutch, American) e s Pl spin (9.24) me The total magnetic moment of any electron is just the sum of its orbital and spin moments e (L+ 2S) 2me porb+ spin (9.25) ltot As we describe in the next two sections, much of the evidence for the elec- tron's spin comes from the repeated success of the formula (9.25) in explaining a wide variety of experimental results. The suggestion that the electron has a spin angular momentum and a Uhlenbeck (center) and Goudsmit (right) are shown here with col- league Oskar Klein (left). In 1925 Goudsmit and Uhlenbeck, while both graduate students at Leiden, showed that several puzzles in inined nding magnetic moment given, as we now know, by (9.24)] is gener- el Goudsmit and George Uhlenbeck corre