Understand that, for many purposes, a system can be treated as a point-like particle with its mass concentrated at the center of
mass. a complex system of objects, both point-like and extended ones, can often be treated as a point particle, located at the system's center of mass. such an approach can greatly simplify problem solving.
Treating the system as a point-like particle allows us to assign a quantity to the object and monitor this quantity throughout any changes. The complexity of the system which includes geometry, appearance, and extensions can complicate the studying of the system.
