§8.5 — Non-Conservative Forces

Not all forces are conservative. Friction, air drag, and other dissipative forces depend on velocity and cannot be derived from a potential energy…

§8.6 — Energy Diagrams

An energy diagram is a graph of potential energy $U(x)$ as a function of position. It encodes rich information about motion without requiring…

§8.7 — Complex Systems

Most real systems involve multiple particles, multiple degrees of freedom, or constraints that couple the motion of different parts. A rigid body…

Chapter 8 — Flashcards

Potential Energy and Conservation — the most powerful tools in physics! Master potential energy, conservative forces, energy conservation, and energy…

Chapter 8 — Q&A

Here are questions that often come up while learning this chapter — with short, clear answers. Questions are ordered from foundational to advanced.…

§9.1 — Center of Mass

The center of mass (or center of gravity) is the point that represents the overall motion of a system. For a rigid body or system of particles, it is…

Chapter 9 — Flashcards

Center of Mass and Momentum — the framework for understanding multi-body systems! Master the center of mass, linear momentum, collisions, and impulse…

Chapter 9 — Q&A

Here are questions that often come up while learning this chapter — with short, clear answers. Questions are ordered from foundational to advanced.…

§9.2 — Motion of Center of Mass

One of the most powerful results of classical mechanics is that the center of mass of a system behaves like a single particle with mass equal to the…