Life & Character** - **Isaac Newton was born prematurely on Christmas day 1642 (4 January 1643, New Style) in Woolsthorpe, a hamlet near Grantham in

With his mother's return to Woolsthorpe in 1653,

Although *Géométrie* and other forms of mathematics far in advance of *Elements*. Barrow, himself a gifted mathematician, had yet to appreciate

In 1665 *Principia *(1687).

In April 1667,

In the first of a series of bitter disputes,

In 1678,

In 1666, as tradition has it,

Meanwhile, in the coffeehouses of *De Motu* of 1684. From that seed, after nearly two years of intense labor, the *Philosophiae Naturalis Principia Mathematica* appeared. Arguably, it is the most important book published in the history of science. But if the *Principia* was

Although the *Principia* was well received, its future was cast in doubt before it appeared. Here again Hooke was center stage, this time claiming (not without justification) that his letters of 1679-1680 earned him a role in *Principia* altogether, finally denouncing science as 'an impertinently litigious lady.' *Opticks* (1704) and virtually withdrew from the Royal Society until Hooke's death in 1703.

After publishing the *Principia*,

During his *Opticks*, based largely on work completed decades before. He was knighted in 1705.

Although his creative years had passed,

Scientific Achievements

Mathematics - The origin of *Géométrie*, John Wallis' *Arithmetica infinitorum*, and other works by prominent mathematicians. But between 1664 and his return to

*De analysi* (*On Analysis*),which went unpublished until 1711. In 1671, *Methodus fluxionum et serierum infinitarum* *(The Method of Fluxions and Infinite Series*, 1736). In addition to these works, *Opticks* of 1704.

Optics. * Philosophical Transactions of the Royal Society*. This paper, and others that followed, drew on his undergraduate researches as well as his Lucasian lectures at

In 1665-1666,

The Crucial Experiment. *experimentum crucis*, demonstrated his theory of the composition of light. Briefly, in a dark room

*Optical Lectures* (1728), supplement other researches published in the Society's Transactions dating from February 1672.

The Opticks. The *Opticks* of 1704, which first appeared in English, is *Opticks* was 'not to explain the Properties of Light by Hypotheses, but to propose and prove them by Reason and Experiments.' Divided into three books, the *Opticks* moves from definitions, axioms, propositions, and theorems to proof by experiment. A subtle blend of mathematical reasoning and careful observation, the *Opticks* became the model for experimental physics in the 18th century.

The Corpuscular Theory. But the *Opticks* contained more than experimental results. During the 17th century it was widely held that light, like sound, consisted of a wave or undulatory motion, and

At various points in his career *Opticks* of 1717,

The question of periodicity arose with the phenomenon known as '*Opticks*, Newton describes a series of experiments concerning the colors of thin films. His most remarkable observation was that light passing through a convex lens pressed against a flat glass plate produces concentric colored rings (Newton's rings) with alternating dark rings. Newton attempted to explain this phenomenon by employing the particle theory in conjunction with his hypothesis of 'fits of easy transmission [refraction] and reflection.' After making careful measurements, Newton found that the thickness of the film of air between the lens (of a given curvature) and the glass corresponded to the spacing of the rings. If dark rings occurred at thicknesses of 0, 2, 4, 6... , then the colored rings corresponded to an odd number progression, 1, 3, 5, 7, .... Although Newton did not speculate on the cause of this periodicity, his initial association of 'Newton's rings' with vibrations in a medium suggests his willingness to modify but not abandon the particle theory.

The *Opticks* was Newton's most widely read work. Following the first edition, Latin versions appeared in 1706 and 1719, and second and third English editions in 1717 and 1721. Perhaps the most provocative part of the *Opticks* is the section known as the 'Queries,' which Newton placed at the end of the book. Here he posed questions and ventured opinions on the nature of light, matter, and the forces of nature.

Mechanics. Newton's research in dynamics falls into three major periods: the plague years 1664-1666, the investigations of 1679-1680, following Hooke's correspondence, and the period 1684-1687, following Halley's visit to Cambridge. The gradual evolution of Newton's thought over these two decades illustrates the complexity of his achievement as well as the prolonged character of scientific 'discovery.'

While the myth of

The next step was to test the inverse square relation against empirical data. To do this ^{2}) of the gravitational acceleration on earth. But

In late 1679 and early 1680 an exchange of letters with Hooke renewed *Attempt to Prove the Motion of the Earth* (1674). Here Hooke proposed that planetary orbits result from a tangential motion and 'an attractive motion towards the centrall body.' In later letters Hooke further specified a central attracting force that fell off with the square of distance. As a result of this exchange

When Halley visited *Principia* and saw it through the press to publication in July 1687.

The Principia. *Principia* begins with eight definitions and three axioms, the latter now known as

In Book II of the *Principia*,

In Book III, subtitled the *System of the World*, Newton extended his three laws of motion to the frame of the world, finally demonstrating 'that there is a power of gravity tending to all bodies, proportional to the several quantities of matter which they contain.' ^{2}; that is, that all matter is mutually attracted with a force (F) proportional to the product of their masses (Mm) and inversely proportional to the square of distance (R2) between them. G is a constant whose value depends on the units used for mass and distance. To demonstrate the power of his theory,

Perhaps the most powerful and influential scientific treatise ever published, the *Principia* appeared in two further editions during

Other Researches. Throughout his career

## 2 comments:

hi

nice and wuite informative blog

AS

http://hummingwords.blogspot.com/

very informative i mean

Post a Comment