跳到正文
The Lumenary
本科低年级Applied Mathematics计划中

Classical mechanics

Newton's laws as differential equations, conservation of energy and momentum, oscillators, central forces and Kepler's laws, and an introduction to Lagrangian mechanics.

math.applied.classical-mechanics

本主题的课程尚未编写。下面的提纲是课程地图的一部分,尚未经过审校。

前置知识

38 项必需的前置知识(一直追溯到底)

你将学会

  • Solve the equations of motion of projectiles and of harmonic oscillators, with and without damping.
  • Use conservation of energy and angular momentum to analyse motion under a central force and derive Kepler's laws.
  • Derive equations of motion from a Lagrangian using the Euler–Lagrange equations.

定义

  • Newton's second law: F = ma, where the acceleration a is the second derivative of position.
  • A force field F is conservative if F = −∇V for some potential V.
  • The Lagrangian of a system is L = T − V, kinetic energy minus potential energy.

定理

  • For conservative forces the total energy T + V is conserved.
  • Under a central force, angular momentum is conserved and the motion stays in a plane.
  • Bound orbits under an inverse-square attractive force are ellipses (Kepler's first law).

常见误解

  • Thinking a force is needed to keep an object moving at constant velocity.
  • Confusing mass with weight.

可选发现

  • Smooth manifolds Configuration spaces are manifolds, and Hamiltonian mechanics lives on cotangent bundles with their symplectic structure.

学习路径

延伸阅读

  • V. I. Arnold, Mathematical Methods of Classical Mechanics
  • John R. Taylor, Classical Mechanics (2005)