page_title: Center of mass
hierarchical_section_title: Center of mass
context_page_description: Center of mass or barycenter of a system is the average position of all the mass in a system.
  In a rigid body, the centre of mass is always in the same place. In a loose collection the center of mass may be in space, as it is in the Solar System. Also, as planets' orbits change slightly, so will the position of the barycenter.
  A simple way to understand the concept of barycenter is to push a supermarket trolley. If you hold only one corner and push, it will only go in a straight line when you push through the centre of mass. Otherwise a turning force is created. This shows that the mass acts as if it were only in one place.
  The center of gravity is a closely related term. It is the point where an object can be balanced perfectly by a sharp point holding it up under the object. It is the center of mass acting in a gravitational field.
context_section_description: Center of mass or barycenter of a system is the average position of all the mass in a system.
  In a rigid body, the centre of mass is always in the same place. In a loose collection the center of mass may be in space, as it is in the Solar System. Also, as planets' orbits change slightly, so will the position of the barycenter.
  A simple way to understand the concept of barycenter is to push a supermarket trolley. If you hold only one corner and push, it will only go in a straight line when you push through the centre of mass. Otherwise a turning force is created. This shows that the mass acts as if it were only in one place.
  The center of gravity is a closely related term. It is the point where an object can be balanced perfectly by a sharp point holding it up under the object. It is the center of mass acting in a gravitational field.
caption: Diagram of an educational toy that balances on a point: the CM (C) settles below its support (P). Any object whose CM is below the fulcrum will not topple.