Isolated System – What is it, concept, characteristics and examples

We explain what an isolated system is, its characteristics and various examples. Also, what are open and closed systems.

thermo insulated system
A thermos is an isolated system, at least for a time.

What is an isolated system?

In thermodynamic physics, an isolated system is understood to be those systems in which there is no exchange of matter or energy with the environment, due to the action of some type of barriers that allow the conservation of the system’s resources, at the same time that they impede the entry of resources from outside.

In this they are distinguished from closed systems, which in the same field of physics are capable of exchanging energy with the environment (but not matter), and even more from open systems, in which the exchange of both things occurs freely. .

According to the General Systems Theory that emerged in the mid-twentieth century, a system is a portion of the universe that, for study, is considered separate and delimited from its environment. This perspective is used in both natural and social sciences.

However, it is mostly in the realm of physics that the term isolated system is used. Its operation, in this area, is determined by the Conservation Laws, according to which certain magnitudes remain constant within an isolated system, at least for a time. This applies to both mass, energy, electric charge, angular momentum, and momentum.

Characteristics of an isolated system

Isolated systems are characterized by the following:

  • They have barriers of some kind, known as insulators, which significantly and notoriously limit the exchange between the inside and the outside.
  • As long as they stay isolated its resources and properties remain constant and stable, that is, invariable: nothing comes out and nothing comes in, or at least not in significant proportions.
  • There is no such thing as total insulation, or perfect insulators: all have some margin of loss or leakage, but in many cases this margin is usually negligible or insignificant during the study of the system.
  • In many cases, the insulation produced in the system is temporary, and given a sufficient amount of time, your margin of loss or inaccuracy becomes evident.

Examples of isolated systems

cable insulated system
Although a cable is used to exchange energy, before it is connected it is an isolated system.

Possible examples of an isolated system are the following:

  • A thermal container that maintains the temperature of substances, such as a beach cellar or a thermos for hot coffee.
  • Winter clothes that isolates us from cold air and therefore prevents us from losing body heat at a noticeable rate.
  • Electrical conduction cables that are covered with insulating material (rubber or plastic) to minimize the loss of electrical power in the transit to our homes (and, also, that some passer-by is electrocuted).
  • Rubber boots that we use to walk in a flooded terrain, or in the snow, which prevent the entry of water at our feet.

Open systems

Open systems are those who freely exchange information, matter and / or energy with the environment, without there being limits or barriers that significantly restrict the traffic between inside and outside. They are, therefore, systems of infinite but external resources, which are in constant connection with the environment.

Closed systems

Closed systems are those in which there is no exchange of matter between the inside and the outside. Therefore, they have limited but their own resources. However, it may or may not exchange energy with the environment. In practice, closed systems are much more frequent than isolated systems.