There are several types of systems in thermodynamics: insulated and non-insulated. Where they meet, when applied, shows how useful they can be and how to care for them. Otherwise, if such systems turn out to be harmful to human work, how to get rid of them.
What it is?
An isolated system is absolutely any accumulation of atoms and molecules (thing, planet, human body) that stores the energy of all matter in itself. Such a system is completely isolated from the outside world, it is also called closed.
The essence of an isolated system is that, with all its desire, it will not share heat, it will not waste energy, it will have to be taken away from it by force. For example, you can look at the aquarium. Inside it, processes take place: the fish die, the water deteriorates, the shells are destroyed. But the aquarium does not contact the external environment.
Another example of an isolated system is an iron - it will not spend energy itself, it will not share substances. This phenomenon is observed in tank engines, the solar system - in everything that does not share energy with others.
A closed insulated system cannot be attributed to a car - it moves at a certain speed itself! Also do not include teapots, plants, living organisms - they share substances with the outside world. Living organisms secrete metabolic products, plants - oxygen, kettle - steam when boiling.
An interesting fact: closed is called such a system, where the sum of the forces and work produced is zero, and isolated - where the bodies simply act separately from other systems. Moreover, an isolated system is not always closed, but a closed system will necessarily be isolated.
In movements - a trap
There is one caveat: they cannot move by themselves, but if someone moves them, the rule is not violated. So, if you take an isolated system and drop it from a height, accidentally drop it, drop it from a parachute - it does not matter, it will not cease to be isolated. Unless, of course, you break it up under such actions - the same water bottle thrown from a height will release all the water out - share the substance with other systems - which means that the system will no longer be closed.
A pistol and a bullet fit this description - it does not work without a finger on the trigger, a heavy body and the Earth - nothing happens if you do not push the body into the soil.
Heat must also be taken into account
An isolated system in thermodynamics is a macrobody that never shares anything at all: energy, matter and heat do not go beyond the system. As an example - a thermos. He maintains the degree of tea poured into it, he will not forcibly share the drink without human intervention (open and pour it himself), and he does not spend energy anywhere.
Moreover, an isolated system always seeks to come into thermodynamic equilibrium, and someone else is needed to get it out of this state. That is, if you give an example of the same thermos, then with a long stay in the environment, tea will still cool. Therefore, we need a person who again floods it with hot tea, and the system will again be thermodynamically isolated.
Why is it needed?
The concept of an isolated system covers many mechanisms, systems and ecosystems. A person needs to understand how they are arranged in order to properly care for them. If this is an aquarium, then before you get into it with arms and legs, trying to clean it, you must first see how to do everything so as not to disturb it. If these are mechanisms or equipment - how to use them so that then it would not be painfully painful to repair them.
At the same time, if we take it on a global scale, the desert is also an isolated system: certain mechanisms of vital activity occur inside it, which do not go beyond it. Forests, steppes, volcanoes, and the atmosphere serve as relatively isolated ecosystems. People, not understanding how they work, sometimes they themselves don’t realize what scale of trouble they create.
There is one more “but”. An isolated system will never exist completely separate from other systems. But this concept exists. It is convenient for making calculations in mathematics, thermodynamics, chemistry, and physics. All the energy and substance that the isolated system emits is taken for zero and is operated on with the numbers that are needed at the moment.
We isolate the non-insulating!
Even an open system can become isolated if it is fenced off by something from the environment. The adiabatic system acts as a partition, which serves as a shell for an open system, making it closed. It can be compared with the foil that wraps an object in an attempt to protect it from sunlight.
If we look in a broader sense, then the atmosphere for the Earth can serve as an example - it protects the planet from cosmic influence and serves as a shell that gives us life.
There is a law of conservation of momentum for a closed isolated system: The sum of the pulses in a closed system remains constant, as if the bodies did not interact with each other inside the system. And this is correct: although the strength of impulses can change with time, circumstances, opportunities, their sum will still remain constant.
In the end - a fat point ...
Thus, the conclusion is as follows:
- An isolated system does not depend on the environment, as far as it is possible at all, producing energy, work and matter within itself. She will remain constant, while striving for balance.
- A closed isolated system will also not depend on environmental conditions, do not isolate anything from itself, but work in it will total zero. That is, the law of conservation of momenta will apply more to such a system than to an open one.
- An isolated system in thermodynamics will not depend on the heat of the environment. Builders try to achieve this state when they insulate houses. By the way, the foam can easily serve as an adiabatic shell for the home, making it an isolated system.
- An isolated system does not exist in principle: everything interacts with something. If you close the aquarium, the water will be poor in oxygen, and the fish will die. In any case, they remain in the red.
Science needs isolated systems in order to ensure the purity of the experiment - some values can be neglected. And in life - they need proper care and use.