The Physics system is comprised of several extensions each providing their own technology and API. Here are a few basic examples of Newtonian physics including Rigid Bodies, Triggers, and Vehicles.
Examples of Newtonian Physics
Physics and USD Schemas
A schema developed by NVIDIA in collaboration with Pixar and Apple standardizing the representation of mass distribution, collision behavior and other data necessary for rigid-body dynamics.
You should be familiar with this before using our Physics Schema: https://openusd.org/release/api/usd_physics_page_front.html
Physics Demo Scenes
Many python examples using our cutting edge physics technology are demonstrated in the Physics Demo Scenes that can be found in Omniverse USD Composer. To open it go to the Window menu, Simulation sub-menu and then select Demo Scenes in the Physics section.