physical system
Also known as physical subsystem, subsystem (physical), system (physical)
portion of the physical universe chosen for analysis; everything outside the system is known as the environment
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Weather map as an example of a physical system
A physical system is a collection of physical objects under study. The collection differs from a set; the objects must coexist and have some physical relationship. In other words, it is a portion of the physical universe chosen for analysis. Everything outside the system is known as the environment, which is ignored except for its effects on the system.