Classical mechanics
Theory · 17th to 19th century, Italy, England, and France · Physics, stage 2: Map the theories
Classical mechanics is the framework for describing how objects move under forces. Galileo established that motion continues without a cause and that bodies fall at the same rate regardless of weight, overturning the standing account inherited from Aristotle. Newton then unified terrestrial and celestial motion in the Principia of 1687, showing that the same law of gravitation governs a falling apple and the orbit of the Moon. Over the following century Lagrange and Hamilton reformulated the same physics in terms of energy rather than force, which turned out to be the form that generalises to quantum mechanics. Classical mechanics remains exactly right for everyday speeds and sizes and fails only near the speed of light or at atomic scale.
What it claims
- An object keeps its velocity unless a force acts on it.
- The acceleration a force produces is proportional to the force and inversely proportional to the mass.
- Every force is matched by an equal and opposite force on the other body.
- The same law of gravitation applies to falling objects on Earth and to bodies in orbit.
Key ideas
People
Sources
- Classical mechanics English Wikipedia
- Newton's Philosophiae Naturalis Principia Mathematica Stanford Encyclopedia of Philosophy
- Mechanics Britannica
