Isaac Newton - Some Comments
One of the major scientific works which have contributed to a great leap forward in our understanding of the word is Isaac Newton’s Philosophiae Naturalis Principia Mathematica. Written about 300 years ago and published in 1687, most of the idea and laws it presents are valid today unlike any many other theories of similar vintage. Given the norm of constant change in scientific understanding, the enduring relevance of this work is even more outstanding.
The Principia contains the main point of what is known as Newtonian or classical mechanics (summarized in Newton’s three laws of motion) the demonstration that the force law for elliptical motion is inverse-square in nature and the universality of the law of gravitation (applying not just to the motion of planets and other heavenly bodies but also to object on earth.)
Since then it has been shown that Newton’s law of motion do not apply to atomic or nuclear domains, nor to objects that are moving close to the speed of light. However they explain the behavior of everything else including the thrust of a jet engine, the paths of comets, hoe to hit tennis balls and the working of musical instruments.
The story of the apple falling down has been told so often that there has been a suspicion that it may not be true. However Newton himself talked about the event in his old age to his friend, Dr. William Stukeley. This description invites us to the understanding how the great scientist thought through his ideas. Newton wondered why an apple should fall perpendicularly to the ground; why it did not fall sideways or upwards, but always towards the centre of the earth. He concluded that the earth must be drawing it to itself. This source of power lies in the centre of the earth and not on any side of it. This would explain why the apple falls perpendicularly or towards the center.
Furthermore, Newton surmised that if matter attracts other matter, the power acts in proportion to the...