Matter essays

Matter essays Ch.1. The nature of Science; Measurement Systems; Physical - about our physical environment; Physics, Chemistry, Geology, Meteorology Science - a body of knowledge AND a method hypothesis - a tentative explanation; needs testing by a controlled experiment scientific law - important relationship observed in nature; occurs consistently (example: The Law of Universal Gravitation) scientific principle - specific set of relationships (example: The Archimede's Principle) model - gives an idea of the properties of a physical system (example: scale model of the Solar system) theory - a confirmed hypothesis, based on extensive experimental evidence (example: plate tectonics theory; atomic theory) Click on this link to view an impressive voyage through the various scales in the Universe - "the powers of ten" demo from Florida State University. PHYSICA means "NATURE" in ancient Greek. Ancient Greek philosophers were trying to discover the laws of Nature by pure reasoning, based on logic and general philosophical principles; mostly without experimenting. Modern Science began with Galileo's experiments (in 16th-17th century): not just reasoning, but observation -> hypothesis -> checking the hypothesis with experiments. Aristotle's intuitive thinking lead to the wrong conclusion that "heavier bodies fall faster" Galileo's numerous experiments: "all bodies fall at the same rate, reach ground at the same time". Any difference is explainable by air resistance. Newton: the theory of gravity. Not obvious that falling bodies and planets move under the same rules; experimentally proven. Need for objective description of properties; need for standards. Measurements and Measurement Systems (English, SI, CGS) ...