when was it published?
5 July 1687
Philosophiæ Naturalis Principia Mathematica
first published 5 July 1687.
an isosceles triangle has two sides of equal length UNANSWERABLE how did it gat the name? "Isosceles" is made from the Greek roots "isos" (equal) and "skelos" (leg). how can one find it's area? The same area formula can also be derived from Heron's formula for the area of a triangle from its three sides. where all can it be applied? Celestial mechanics what is it about? It  is the branch of astronomy that deals with the motions of objects in outer space. who all have proposed studies on it? Isaac Newton, Gottfried Leibniz, Pierre-Simon Laplace when was the first scientist born? 25 December 1642 where? Lincolnshire what were his famous findings? He formulated the laws of motion and universal gravitation. what does the latter mean? It  is usually stated as that every particle attracts every other particle in the universe with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. how is he related to the field of optics? Newton lectured on optics. During this period he investigated the refraction of light, demonstrating that the multicoloured spectrum produced by a prism could be recomposed into white light by a lens and a second prism. which of his works brought him the fame? His book "Philosophiæ Naturalis Principia Mathematica" laid the foundations of classical mechanics. what does this book deal with? It speaks about Newton's laws of motion, forming the foundation of classical mechanics; Newton's law of universal gravitation; and a derivation of Kepler's laws of planetary motion
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Philosophiæ Naturalis Principia Mathematica [SEP] Introduction
Philosophiæ Naturalis Principia Mathematica (Latin for "Mathematical Principles of Natural Philosophy"), often referred to as simply the Principia (), is a work in three books by Isaac Newton, in Latin, first published 5 July 1687. After annotating and correcting his personal copy of the first edition, Newton published two further editions, in 1713 and 1726. The "Principia" states Newton's laws of motion, forming the foundation of classical mechanics; Newton's law of universal gravitation; and a derivation of Kepler's laws of planetary motion (which Kepler first obtained empirically). The "Principia" is considered one of the most important works in the history of science.