1. Basic Concepts 1.1 Ideal model Particle: It is the body that has only the mass, but not its shape and size a pingpong the earth Which one is a particle? Ideal Models: Simple pendulum, rigid body, point charge, harmonical oscillator.1.1 Ideal Model ◼ Particle: It is the body that has only the mass, but not its shape and size. Which one is a particle? a pingpong the earth Ideal Models: Simple pendulum, rigid body, point charge, harmonical oscillator… 1. Basic Concepts