Physical body
In physics, a physical body or physical object (sometimes simply called a body or object) is a collection of matter with some common attributes, most important, the spacial location.
Examples of models of physical bodies include, but are not limited to a particle, several interacting smaller bodies (particles or other), and continuous media.
The common conception of physical objects includes that they have extension in the physical world, although there do exist theories of quantum physics and cosmology which may challenge[how?] this.
In modern physics, "extension" is understood in terms of the spacetime:
roughly speaking, it means that for a given moment of time the body has some location in the space, although not necessarily a point.
A physical body as a whole is assumed to have such quantitative properties as mass, momentum, electric charge, other conserving quantities, and possibly other quantities.
A body with known composition and described in an adequate physical theory is an example of physical system.
