What is Classical mechanics: Definition and 1000 Discussions

Classical mechanics is a physical theory describing the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars, and galaxies. For objects governed by classical mechanics, if the present state is known, it is possible to predict how it will move in the future (determinism), and how it has moved in the past (reversibility).
The earliest development of classical mechanics is often referred to as Newtonian mechanics. It consists of the physical concepts based on foundational works of Sir Isaac Newton, and the mathematical methods invented by Gottfried Wilhelm Leibniz, Joseph-Louis Lagrange, Leonhard Euler, and other contemporaries, in the 17th century to describe the motion of bodies under the influence of a system of forces. Later, more abstract methods were developed, leading to the reformulations of classical mechanics known as Lagrangian mechanics and Hamiltonian mechanics. These advances, made predominantly in the 18th and 19th centuries, extend substantially beyond earlier works, particularly through their use of analytical mechanics. They are, with some modification, also used in all areas of modern physics.
Classical mechanics provides extremely accurate results when studying large objects that are not extremely massive and speeds not approaching the speed of light. When the objects being examined have about the size of an atom diameter, it becomes necessary to introduce the other major sub-field of mechanics: quantum mechanics. To describe velocities that are not small compared to the speed of light, special relativity is needed. In cases where objects become extremely massive, general relativity becomes applicable. However, a number of modern sources do include relativistic mechanics in classical physics, which in their view represents classical mechanics in its most developed and accurate form.

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  1. I

    Which classical mechanics textbook is best for me?

    Which one would you recommend for me? Topics I'd like to have covered (most important ones): -Euler-Lagrange's equations -Lagrange's and Hamilton's approach to mechanics -Noether's theorem -KAM theorem -Bertrand's theorem -Poisson's brackets Plenty of examples and exercises would be...
  2. M

    Classical Mechanics collission particles

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  3. L

    Classical Mechanics: Gravitation, SHM

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  4. B

    When Will a Particle Reach the Force Center Under an Inverse Cubed Law?

    Homework Statement At t0 = 0 a particle of mass m is released from rest at x0 = b > 0 away from a fixed origin of force that attracts the particle according to the law: F=-k/x^3 where k >0 is a constant. At what time the particle will reach the force center x =0? Homework Equations I...
  5. M

    Classical Mechanics: Repelling Force and Motion Equations for F=ma

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  6. A

    Instantaneous force propagation in classical mechanics

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  7. Z

    Classical Mechanics (Taylor) 1.39

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  8. Z

    Do I need Classical mechanics and waves in order to understand Quantum mechanics?

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  9. F

    Courses What is the course Classical Mechanics ?

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  10. M

    What is the acceleration at point A on a rotating merry go round?

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  11. N

    Taking upper level classical mechanics early?

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  12. M

    Classical Physics: Is Research Still Ongoing?

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  13. C

    What are the central pillars of classical mechanics?

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  14. X

    Possible new reformulation of classical mechanics

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  15. C

    Similar Classes? (Statics and Classical Mechanics)

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  16. L

    Quantum mechanics vs Classical mechanics

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  17. S

    Solve Classical Mechanics Homework Statement

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  18. S

    Solving a differential equation in classical mechanics

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  19. S

    Power series question involving classical mechanics

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  20. C

    Classical Mechanics Accelerated Frame/Rotation Problem

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  21. C

    Classical Mechanics Accelerated Frame/Rotation Problem

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  22. P

    Classical Mechanics Video Lectures

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  23. C

    Best Classical Mechanics Textbook

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  24. 1

    Classical mechanics - Time dependent Hamiltonian and Lagrangian

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  25. fluidistic

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  26. P

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  27. M

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  28. D

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  29. B

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  30. H

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  31. P

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  32. W

    Is research still being done in Classical Mechanics? (and another question)

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  33. S

    Upper Division Classical Mechanics for Dummies?

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  34. P

    Project Ideas for Classical Mechanics

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  35. S

    Self Study book for Classical Mechanics?

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  36. C

    Solving Classical Mechanics #3d - Momentum p in Jaccobi Function

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  37. S

    Classical Mechanics, clyinder inside a cylinder.

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  38. P

    Advise on how to study (and catch up) in Classical Mechanics

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  39. J

    Which textbook is the best for learning classical mechanics?

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  40. H

    Help with classical mechanics question

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  41. P

    A bunch of Classical Mechanics online Resources( lecture notes)

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  42. A

    Classical mechanics reference book

    Hi All, Kindly suggest me an alternative book for "Classical Mechanics by Goldstein". I am finding it little bit difficult to understand so if i can find any alternate book which is little less complicated than Goldstein it will be helpful for me. I am concentrating on the below mentioned...
  43. L

    Why Can't Stefan-Boltzmann Law Be Explained in Classical Mechanics?

    I've looked all over the internet, and can't find a decent explanation. Could someone please explain why the stefan-boltzmann radiation law of I = oT^4 be explained in classical mechanics rather then quantum? It's urgent, sorry to be pushy. Cheers.
  44. J

    Relativistic covariance in classical mechanics?

    Hi friends, long time ago I noticed the following interesting similarity between classical mechanics and relativity. Consider particle moving in an external field and the action defined as a function of actual time t and position q: S(t,q) = \int_0^t L(q^r,\dot q^r,t´)dt´ The motion q^r is...
  45. J

    Hydrogen atom obeying classical mechanics rather than quantum mechanics

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  46. N

    Is it reasonable to go straight from general physics to classical mechanics?

    I'm a biochemistry major with most of my requirements out of the way. Fall term my schedule will be: Physical chemistry, intro to real analysis (junior level). This is 8 credits, but to maintain full financial aid I need 12 credits. I recently found out that I am 12 credits away from a physics...
  47. V

    Cannot see where potential enegy comes from in classical mechanics

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  48. J

    Lectures on Classical Mechanics - J. Baez

    Graduate course lecture notes - Excellent! http://math.ucr.edu/home/baez/classical/texfiles/2005/book/classical.pdf" jf
  49. T

    Classical Mechanics - Pulleys System

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  50. T

    Classical Mechanics - Block Friction Problem

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