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The electron is a charged particle with charge − e, where e is the unit of elementary charge. Its angular momentum comes from two types of rotation: spin and orbital motion. From classical electrodynamics, a rotating distribution of electric charge produces a magnetic dipole, so that it behaves like a tiny bar magnet.
The Weiss magneton was experimentally derived in 1911 as a unit of magnetic moment equal to 1.53 × 10 −24 joules per tesla, which is about 20% of the Bohr magneton. In the summer of 1913, the values for the natural units of atomic angular momentum and magnetic moment were obtained by the Danish physicist Niels Bohr as a consequence of his ...
In atomic physics, the Bohr model or Rutherford–Bohr model was the first successful model of the atom. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford 's nuclear model , it supplanted the plum pudding model of J. J. Thomson only to be replaced by the quantum atomic model in the 1920s.
The magnetic field between poles (see the figure for Magnetic pole model) is in the opposite direction to the magnetic moment (which points from the negative charge to the positive charge), while inside a current loop it is in the same direction (see the figure to the right). The limits of these fields must also be different as the sources ...
In the Stoner model, the spin-only magnetic moment (in Bohr magnetons) per atom in a ferromagnet is given by the difference between the number of electrons per atom in the majority spin and minority spin states. The Stoner model thus permits non-integral values for the spin-only magnetic moment per atom.
In 1913, the Bohr model of the atom abandoned the efforts to explain why its bound electrons do not radiate by postulating that they did not radiate. This was later subsumed by a postulate of quantum theory called Schrödinger's equation. In the meantime, our understanding of classical nonradiation has been considerably advanced since 1925.
Bohr had calculated the wavelengths emitted by hydrogen very accurately. [20] The fundamental assumption of the Bohr model concerns the possible binding energies of an electron to the nucleus of an atom. The atom can be ionized if a collision with another particle supplies at least this binding energy. This frees the electron from the atom, and ...
When an isolated atom is placed in a magnetic field there is an interaction because each electron in the atom behaves like a magnet, that is, the electron has a magnetic moment. There are two types of interaction. Diamagnetism. When placed in a magnetic field the atom becomes magnetically polarized, that is, it develops an induced magnetic moment.