History Of Physics

History Of Physics

Physics began when man first started to study his surroundings. Early applications of physics include the invention of the wheel and of primitive weapons. The people who built Stone Henge had knowledge of physical mechanics in order to move the rocks and place them on top of each other. It was not until during the period of Greek culture that the first systematic treatment of physics started with the use of mechanics. Thales is often said to have been the first scientist, and the first Greek philosopher. He was an astronomer, merchant and mathematician, and after visiting Egypt he is said to have originated the science of deductive geometry. He also discovered theorems of elementary geometry and is said to have correctly predicted an eclipse of the sun. Many of his studies were in astronomy but he also observed static electricity. Phythogoras was a Greek philosopher. He discovered simple numerical ratios relating the musical tones of major consonances, to the length of the strings used in sounding them. The Pythagorean theorem was named after him, although this fundamental statements of deductive geometry was most likely first an idea from Egyptian methods of measurements. With the help of his followers he discovered that the earth was a sphere, but he did not believe it revolved around the sun. Democritus was the leader of a group called Atomists. Although they were unable to prove that matter was made up of small particles, they were the first to come up with the idea. Democritus believed that atoms differed in size, shape, and movement but were all made of the same substances. Aristotle was the most important scientific philosopher in Greece. He believed that all matter on earth consisted of four pure substances or elements, which were earth, air, fire, and water. He also believed that the earth was the centre of the universe, and that anything beyond the earth consisted of a fifth pure substance called quintessence. Archimedes was an inventor and mathematician, who discovered several basic scientific principles and developed a number of measuring techniques. Ptolemy was an Egyptian astronomer.

 He developed a model for predicting the positions of the sun, moon, stars, and planets. Like Aristotle, he believed that the earth was the center of the universe. Between 400 AD. and 1000 AD. Most educated people in Western Europe looked to religion rather than scientific investigation to answer their questions about the laws of nature. At the same time Arabic scholars were correcting Ptolemy system of astronomy and performing experiments in optics and mechanics. As trade increased between Arab countries and western countries, their work and Greek scientific documents became available to western culture. During the 1200's St. Thomas Aquinas reconciled Aristotle's beliefs with church principles. During this time Roger Bacon an English scholar conducted studies in optics. During the Renaissance there were many social, economic and political changes that produced new approaches to science. The famous Italian painter Leonardo da Vinci conducted studies in motion and hydraulics. The polish astronomer Nicolaus Copernicus proposed a system in which the sun was placed at the centre of the universe and the earth was one of the planets orbiting the sun. In the 1600's Johannes Kepler, a German astronomer constructed a new and accurate model of the solar system. Rene Descartes, a French philosopher and mathematician developed the concept of inertia ( that objects maintain their state of motion unless disturbed ). At this time people began to realise that the physical world was governed by natural laws and that it was possible to discover those laws through careful measurement under controlled conditions. Galileo, an Italian physicist developed a number of telescopes to study the heavens, and performed laboratory experiments on the motion of falling bodies. In the 1600's there was a great deal of scientific activity. Sir Isaac Newton, an English scientist, published his Mathematical Principle of Natural Philosophy. He developed three laws of motion and a law of universal gravitation based on the work of Galileo and Descartes. He also invented a new form of mathematics called Calculus. During the Industrial Revolution scientific instruments were produced which were more accurate and enabled scientists to perform more complicated experiments.