Content
The most common classification separates open systems of the closed systems, that is, those that have strong ties with the outside of those that are characterized by functioning regardless of the environment that surrounds them
The closed systems They are those that have an autonomous behavior, and do not have an interaction with other physical agents located outside of it. There is no causal relationship or a correlation with anything that is outside, and therefore they can survive based on their own operating mechanisms.
There are two types of closed systems, according to whether the absence of exchange with the outside is total (which happens in the case of systems isolated) or if there is no exchange of matter, but there is an exchange of energy (which happens in dry closed systems).
It can serve you:
- Examples of Open and Closed Systems
- Examples of Open, Closed and Isolated Systems
Examples of Closed Systems
It is usually called a closed system to those systems that have a deterministic and programmed behavior, and that they have a very small exchange of energy and matter with the environment: so small that it in no way intervenes with the normal development of the system.
Next, the approach to some examples of systems that can function as closed systems:
- A winding watch, which for its operation requires that there is no modification by temperature or the external environment.
- An airplane, that although it expels certain gases to the outside, needs in some cases to be perfectly closed so that life and breathing are possible at so many meters high.
- A nuclear reactor.
- An inflated balloon.
- A car battery.
- A perfectly constructed thermos so that the temperature remains unchanged in the least.
- The planet earth (exchanges energy but not matter)
- The universe, understood as a totality.
- A TV.
- A pressure cooker that does not allow gas to escape.
It can serve you:
- Examples of Open Systems
- Examples of Open, Closed and Semi-closed Systems
characteristics
A characteristic that is peculiar to closed systems is that the very definition of the absence of interaction with the outside requires that all the equations that describe the movement inside such a system can only depend on variables and factors contained in the system.
The choice of the origin of time is arbitrary, and therefore the equations of temporal evolution are invariant with respect to temporal translations: this implies that energy is conserved, which also fits the definition of these systems.
If a system is closed, then any small internal energy change in the system is due to the balance of heat transfer and work done.
However, it is correct to say that if the system increases its energy in a thermodynamic process, the rest of the universe loses the same amount of energy. The first law of thermodynamics, for closed systems, is written as ΔU = ΔQ - ΔW.
