Unit 2 · Force and Translational Dynamics

Chapter 2.2

Newton's Third Law, Tension, and Equilibrium

The floor pushes up on you exactly as hard as you push down on it — always, even in the middle of a jump. So how does anyone ever leave the ground?

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By the end

  1. 01Identify third-law pairs and explain why internal forces cannot accelerate a system's center of mass
  2. 02Model ideal strings and pulleys, with tension uniform along a massless string
  3. 03State Newton's first law and identify an inertial reference frame
  4. 04Apply translational equilibrium axis by axis to find unknown forces

In unit 2

  1. 2.1Systems, the Center of Mass, and Free-Body Diagrams
  2. 2.2Newton's Third Law, Tension, and Equilibrium
  3. 2.3Newton's Second Law and Connected Systems
  4. 2.4Gravitation, Weight, and Apparent Weight
  5. 2.5Friction and Spring Forces
  6. 2.6Circular Motion and Circular Orbits
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