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Sir Isaac Newton

Sir Isaac Newton was born in Lincolnshire, near Grantham, on December 25, 1642. His education took place at Trinity College, in Cambridge where he lived from 1661 to 1696. Here is where he studied physics and astronomy, and created calculus.

Newton became interested in mathematics in the autumn of 1663 when he tried to read an astrology book but could not understand it because he had little knowledge of trigonometry and geometry. What got his mind going was when he read that parallelograms upon the same base and between the same parallels are equal. He then returned back to the astronomy book with a greater understanding and interest.

In the summer of 1665, the plague closed down the University he was attending and during the next two years, he began revolutionary advances in mathematics, optics, physics, and astronomy. During this time he laid the foundations for differntial and integral calculus. He understood that the integrations of a function is merely the inverse procedure to differentiating it, taking differentiation as a basic operation, he produced simple analytical methods that unified many separate techniques previously developed to solve apparently unrelated problems such as areas, tangents, the lengths of curves and the maxima and minima of functions. In his writing, he set down methods of calculating the dimensions of magnitudes concerning hyperbolas.

In 1669 Newton was appointed the Lucasian Chair after Collins barrow resigned his job. Newton\'s first work was on optics and was the topic of his first lecture. In his research, he reached the conclusion that light is not a simple entity. Before his time, people had believed that white light was a basic single entity, but the chromatic aberration in a telescope lens convinced him otherwise. With this hypothesis, he wrongly concluded that telescopes using refracting lenses would always suffer chromatic aberration; therefore he constructed a reflecting telescope. He delayed the publication of a full account of his optical researches until 1704, it dealt with: investigations of the colors of thin sheets, Newton\'s rings, and diffraction of light.

However Newton\'s greatest achievement was his work in physics and celestial mechanics, which climaxed with the theory of universal gravitation. By 1966, he had created his 3 laws and of motion and also discovered the law giving the centrifugal force on a body moving uniformly in a circular path; although his understanding of mechanics of circular motion was incorrect. Newton imagined that the Earth\'s gravity influenced the Moon, counter-balancing its centrifugal force. From his law of centrifugal force and Kepler\'s third law of planetary motion, Newton deduced the inverse-square law.

In 1687, Newton published the Philosophiae naturalis principia. The book is considered the greatest scientific book ever written. In it he analyzes the motion of bodies in resisting and non-resisting media under the action of centripetal forces. The results were applied to orbiting bodies, projectiles, pendulums, and free-fall near the Earth. He further demonstrated that the planets were attracted toward the Sun by a force varying as the inverse square of the distance and generalized that all heavenly bodies mutually attract one another.

After suffering a nervous breakdown in 1693, he retired from his research and decided to leave Cambridge to take up a government position in London, becoming Warden of the Royal Mint in 1696 and Master in 1699. He was knighted in 1705 by Queen Anne, the first scientist to be so honored for his work. The last portion of his life was not easy; it was dominated by the controversy whether he or Leibiniz had invented calculus. He died March 20, 1727 at Kensington, London.

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