Motion of Centre of Mass

Motion of centre of mass has various applications in the real world. It is used for designing stable structures and vehicles, where low centre of mass make them more stable and faster. Even the motion of centre of mass applies to sportspeople, where athletes manipulate their centre of mass to optimise their performance. Apart from that, motion of centre of mass is required in animation and computer graphics to create realistic animations. 

The motion of individual particles relative to the centre of mass shows us how the particles move with respect to this central point. You can consider a frame of reference that moves along with the centre of mass. In this frame, the total momentum of all the particles in the system is nil or zero. 

The centre of mass moves as if all mass of the object is concentrated at one point while all external forces act on it. The motion of the centre of mass follows Newton's Second Law of Motion. That means that you can multiply the total mass of the system with the acceleration, which equals the net total force. The particles within the system have cancelled out internal forces, and do not affect the motion of the centre of mass.