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. S

    Spring Constant in Hooke's Law

    How does one arrive at the following equation to approximate spring constant for solids... using Hooke's Law F ∝-x ⇒ F = -kx and strain∝stress ? k = (m/a2) × (K/ρ)½ where k≡spring constant m ≡ mass of a single atom a ≡ atomic spacing K ≡ bulk modulus ρ ≡ density
  2. REVIANNA

    People lifting themselves with simple fixed pulley

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  3. K

    Engineering Book on Dynamics (Mechanical systems)

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  4. A Baffling Balloon Behavior

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  5. Alexiy

    Find the differential equation and velocity

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  6. K

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  7. J

    From Classical to Quantum Mechanics

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  8. REVIANNA

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  11. REVIANNA

    Classical mechanics:effective spring const

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  12. P

    Classical Possible textbook for Classical Mechanics

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  13. Lito

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  14. AlexGLSY

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  15. N

    Classical mechanics (find trajectory and kinetic energy)

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  16. REVIANNA

    Classical mechanics: Force versus time graph

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  17. S

    Canonical Transformation (two degrees of freedom)

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  18. D

    Shear force and bending moment diagrams question

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  19. M

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  20. jcruise322

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  21. REVIANNA

    Classical mechanics: Momentum and velocity

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  22. B

    Classical A Good Supplement to Goldstein's Classical Mechanics

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  23. dwdoyle8854

    Classical Dynamics -- Falling chain and energy conservation

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  24. T

    Non-arbitrary frame of reference for acceleration?

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  25. Erkan Tur

    Projectile Motion - A classical mechanics problem

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  26. REVIANNA

    Classical mechanics: Projectile Motion

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    Classical mechanics: forces on a pendulum

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  28. REVIANNA

    Classical mechanics : constant acceleration

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  29. D

    Motion described by differential equations

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  30. I

    A rod in free fall with varying length

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  31. J

    Classical position/velocity probability

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  32. saybrook1

    Project Ideas for Graduate Classical Mechanics and Math Methods

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  33. M

    Analyzing the Motion of a Virtual Ball: A Study in Classical Mechanics

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  34. D

    What Is the Maximum Speed of a Mass in a Driven Damped Oscillator?

    Homework Statement A small block (mass 0.25 kg) attached to a spring (force constant 16 N/m) moves in one dimension on a horizontal surface. The oscillator is subject to both viscous damping and a sinusoidal drive. By varying the period of the driving force (while keeping the drive amplitude...
  35. H

    Classical Supplemental Questions for Classical Mechanics?

    Hello all I currently studying Classical Mechanics from Landau's Vol 1. The book is fantastic however, there are not many problems to do. Are there any good problem books that accompany the text well with solutions? Thanks
  36. D

    Question concerning Doppler effect

    Homework Statement In the picture below, can you help me understand what do equations 3 and 5 mean. They concern the soppler effect but i can't seem to understand what do they represent. Homework Equations ft + fv/c=ft((c+v)/c fd=ft-fr 3. The attempt at solution
  37. J

    Intro Physics Moving Beyond Formulae: How to Think Like a Physicist

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    Time-Reversal Symmetry Explained

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  39. H

    Central Force problems using radial motion equation

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  40. K

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  41. S

    Derivative of the action integral

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  42. Cosmology2015

    How a particle knows about the existence of another particle

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  43. N

    Driving force in simple harmonic oscillator with exponential

    Homework Statement A particle in SHM is subject to a driving force F(t)= ma*e^(-jt). Initial position and speed equal 0. Find x(t). Homework Equations F = -kxdx = mvdv F(t) = F(0)*e^(iωt) x(t) = Acos (ωt +φ) The Attempt at a Solution I have no idea how to deal with the exponential term. I...
  44. D

    What angle does the hanging mass make?

    Homework Statement At a latitude of 50° north a mass is hanged by a massless string. By the means of an angle how much does the mass deviate from the Earth's radius due to rotation of the earth? Consider the Earth as a spherical body. Homework Equations Fcp=mv^2/r w=dθ/dt v=wr The Attempt at a...
  45. Hamza Abbasi

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  46. T

    Classical Looking for a Rigorous Undergraduate Textbook on Classical Mechanics?

    Hi guys I'm searching for a good undergraduate physics textbook on classical mechanics that might has an intro to langranzians and Hamiltonians, that I could tackle right now. I'm actually getting through apostol calculus 1 (just reached partial derivatives). I want it to be hard to follow ,but...
  47. E

    Classical mechanics - hunter and monkey - frame of reference

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  48. K

    Calculating Kinetic Energy and Maximum Speed for a Leaking Oil Tanker Truck

    Homework Statement A truck hauling a big tank of oil starts at position x=D (Chicago) and heads due west (–x direction) toward its destination at x = 0 (Des Moines). At Chicago, the total mass of the loaded truck is M and the mass of oil it is carrying is λM. (Thus M(1–λ) is the "tare" mass =...
  49. P

    What is the relationship between dynamical symmetry and Noether's theorem?

    Hi, I am learning classical mechanics right now, Particularly Noether's theorem. What I understood was that those kinds of transformations under which the the Hamiltonian framework remains unchanged, were the key to finding constants of motion. But here are my Questions: 1. What is...
  50. Titan97

    Different cases of work done done by 3 conservative forces

    Homework Statement Homework Equations W=-ΔU for conservative force. The Attempt at a Solution Let all three forces be conservative. Since particle comes back to where it was, ΔU=0. Hence ΔUAB+ΔUBC+ΔUCA=0 Hence WCA=-WAB-WBC For case A, if both WAB, WBC>0, then WCA<0. Else its greater than...
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