Building a Multi-Body Physics Engine from Scratch with Python & NumPy Mathematical Model Description This project implements a physics-based 2D multi-body dynamical system for particles under gravity with energy dissipation and spin-induced momentum transfer. 1️⃣ System Overview Each particle is a rigid disk of radius r and mass m. The simulation incorporates: • Uniform gravity: g = 9.81 m/s² • Energy loss via coefficient of restitution (e) • Ball-ball elastic collisions • Spin-induced tangentia