When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Thomson problem - Wikipedia

    en.wikipedia.org/wiki/Thomson_problem

    The Thomson problem is a natural consequence of J. J. Thomson's plum pudding model in the absence of its uniform positive background charge. [ 12 ] "No fact discovered about the atom can be trivial, nor fail to accelerate the progress of physical science, for the greater part of natural philosophy is the outcome of the structure and mechanism ...

  3. J. J. Thomson - Wikipedia

    en.wikipedia.org/wiki/J._J._Thomson

    The cathode-ray tube by which J. J. Thomson demonstrated that cathode rays could be deflected by a magnetic field, and that their negative charge was not a separate phenomenon While supporters of the aetherial theory accepted the possibility that negatively charged particles are produced in Crookes tubes , [ citation needed ] they believed that ...

  4. Plum pudding model - Wikipedia

    en.wikipedia.org/wiki/Plum_pudding_model

    An atom with seven electrons arranged in a pentagonal dipyramid, as imagined by Thomson in 1905. The plum pudding model is an obsolete scientific model of the atom.It was first proposed by J. J. Thomson in 1904 following his discovery of the electron in 1897, and was rendered obsolete by Ernest Rutherford's discovery of the atomic nucleus in 1911.

  5. History of atomic theory - Wikipedia

    en.wikipedia.org/wiki/History_of_atomic_theory

    In 1898, J. J. Thomson found that the positive charge of a hydrogen ion was equal to the negative charge of a single electron. [ 70 ] In an April 1911 paper concerning his studies on alpha particle scattering, Ernest Rutherford estimated that the charge of an atomic nucleus, expressed as a multiplier of hydrogen's nuclear charge ( q e ), is ...

  6. Cathode-ray tube - Wikipedia

    en.wikipedia.org/wiki/Cathode-ray_tube

    In 1897, J. J. Thomson succeeded in measuring the mass-to-charge ratio of cathode rays, showing that they consisted of negatively charged particles smaller than atoms, the first "subatomic particles", which had already been named electrons by Irish physicist George Johnstone Stoney in 1891.

  7. Rutherford model - Wikipedia

    en.wikipedia.org/wiki/Rutherford_model

    The plum pudding model of J. J. Thomson also had rings of orbiting electrons. The Rutherford paper suggested that the central charge of an atom might be "proportional" to its atomic mass in hydrogen mass units u (roughly 1/2 of it, in Rutherford's model). For gold, this mass number is 197 (not then known to great accuracy) and was therefore ...

  8. Earnshaw's theorem - Wikipedia

    en.wikipedia.org/wiki/Earnshaw's_theorem

    This led J. J. Thomson in 1904 to his plum pudding model, where the negative point charges (electrons, or "plums") are embedded into a distributed positive charge "pudding", where they could be either stationary or moving along circles; this is a configuration which is non-point positive charges (and also non-stationary negative charges), not ...

  9. Atomic nucleus - Wikipedia

    en.wikipedia.org/wiki/Atomic_nucleus

    The electron had already been discovered by J. J. Thomson. Knowing that atoms are electrically neutral, J. J. Thomson postulated that there must be a positive charge as well. In his plum pudding model, Thomson suggested that an atom consisted of negative electrons randomly scattered within a sphere of positive charge.