Chapter 7 Systems of particles 7-1 The motion of a complex object 7-2 TWo-particle system 7-3 Many-particle system 7-4 Center of mass of solid objects 7-5 Conservation of momentum in a system of particlesChapter 7 Systems of particles 7-5 Conservation of momentum in a system of particles 7-4 Center of mass of solid objects 7-3 Many-particle system 7-2 Two-particle system 7-1 The motion of a complex object