Essay on The Physics Of The Atomic Theory

1714 Words May 23rd, 2016 null Page
The atomic theory was originally introduced in 400 B.C. by Greek philosophers, Democritus and Leucippus, greek philosophers. They came up with the idea that all matter is composed of small particles called atoms. John Dalton, a British chemist and physicist, developed an idea that matter is composed of atoms of different weights and is combined in ratios by weight. He also came up with the idea that atoms are round like balls and are in motion. J. J. Thompson determined the charge to mass ratio of electrons using the cathode ray. Ernest Rutherford discovered alpha, beta, and gamma rays in radiation. He thought the atom was occupied by electrons. He conducted the gold foil experiment which showed that there was something in the middle of the atom. Also known as the nucleus. Max Planck proposed the idea of quantization to explain how a hot glowing object emitted light. Albert Einstein took Planck’s ideas and expanded them. He proposed a quantum of light (the photon) which behaves like a particle. Einstein’s other theories explained the equivalence of mass and energy, the particle wave duality of photons, the equivalence principle, and a special relativity. Niels Bohr succeeds in constructing a theory of atomic structure based on quantum ideas. In 1909, Hans Geiger and Ernest Marsden, under the supervision of Ernest Rutherford, scattered alpha particles off a gold foil and observe large angles of scattering, suggesting that atoms have a small, dense, positively charged…

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