| Themes > Science > Physics > About Physics, Generalities > A Brief History and Philosophy of Physics > The Development of Classical Physics: Mechanics, Heat, Optics, Electromagnetism, Atoms > Mechanics |
Sir Isaac Newton (1642-1727), born the year Galileo died, is the most important figure in the development of mechanics. His three "laws" form the base on which all of mechanics prior to 1900 was constructed. This model of building an edifice of theory on the foundation of a few fundamental definitions and laws is essentially that used by Euclid in his geometry. It became the ideal for all future physical theories, including thermodynamics with three basic laws (zeroth, first and second), optics (laws of reflection and refraction) and electromagnetism (Maxwell's laws). Much of the physics of the hundred years after the death of Newton was spent in applying his three laws to different phenomena. Newton's crowning accomplishment was the application of his mechanics to show that the entire universe obeyed the same laws of nature, as published in his Mathematical Principles of Natural Philosophy (the Principia) in 1687. By assuming that two masses attracted each other with a force inversely proportional to the square of the distance between them, Newton proved that the mechanics which determined how bodies fall on Earth also explained the periodic motions of the planets. However, Newton did not restrict his work to mechanics; he also did extensive studies on light and shares the credit for the invention of calculus with the German, Gottfried Wilhelm Leibnitz (1646-1716), with whom he fought a long battle over who was first. Newton also wrote on theology, and was Master of the Royal Mint. |
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