Application and formulation of the second law of thermodynamics

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Application and formulation of the second law of thermodynamics
Application and formulation of the second law of thermodynamics

How is energy generated, how is it converted from one form to another, and what happens to energy in a closed system? All these questions can be answered by the laws of thermodynamics. The second law of thermodynamics will be discussed in more detail today.

Laws in everyday life

Laws govern daily life. Road laws say you must stop at stop signs. The government demands to give part of their salary to the state and the federal government. Even scientific ones are applicable to everyday life. For example, the law of gravity predicts a rather poor outcome for those who try to fly. Another set of scientific laws that affect everyday life are the laws of thermodynamics. So here are some examples to see how they affect daily life.

The First Law of Thermodynamics

The first law of thermodynamics states that energy cannot be created or destroyed, but it can be transformed from one form to another. This is also sometimes referred to as the law of conservation of energy. So how is itapplies to everyday life? Well, take, for example, the computer you are using now. It feeds on energy, but where does this energy come from? The first law of thermodynamics tells us that this energy could not come from the air, so it came from somewhere.

You can trace this energy. The computer is powered by electricity, but where does the electricity come from? That's right, from a power plant or hydroelectric power plant. If we consider the second, then it will be associated with a dam that holds back the river. The river has a connection with kinetic energy, which means that the river is flowing. The dam converts this kinetic energy into potential energy.

How does a hydroelectric power plant work? Water is used to turn the turbine. When the turbine rotates, a generator is set in motion, which will create electricity. This electricity can be run entirely in wires from the power plant to your home so that when you plug the power cord into an electrical outlet, the electricity enters your computer so it can work.

What happened here? There was already a certain amount of energy that was associated with the water in the river as kinetic energy. Then it turned into potential energy. The dam then took that potential energy and turned it into electricity, which could then enter your home and power your computer.

The second law of thermodynamics in simple terms

The Second Law of Thermodynamics

By studying this law, one can understand how energy works and why everything moves towardspossible chaos and disorder. The second law of thermodynamics is also called the law of entropy. Have you ever wondered how the universe came into being? According to the Big Bang Theory, before everything was born, a huge amount of energy gathered together. The Universe appeared after the Big Bang. All this is good, but what kind of energy was it? At the beginning of time, all the energy in the universe was contained in one relatively small place. This intense concentration represented a huge amount of what is called potential energy. Over time, it spread throughout the vast expanse of our universe.

On a much smaller scale, the reservoir of water held by a dam contains potential energy, since its location allows it to flow through the dam. In each case, the stored energy, once released, spreads out and does so without any effort being made. In other words, the release of potential energy is a spontaneous process that occurs without the need for additional resources. As energy is distributed, some of it is converted into useful energy and performs some work. The rest is converted into unusable, simply called heat.

As the universe continues to expand, it contains less and less usable energy. If less useful is available, less work can be done. Since the water flows through the dam, it also contains less useful energy. This decrease in usable energy over time is called entropy, where entropy isthe amount of unused energy in the system, and the system is just a collection of objects that make up the whole.

Entropy can also be referred to as the amount of randomness or chaos in an organization without organization. As usable energy decreases over time, disorganization and chaos increase. Thus, as the accumulated potential energy is released, not all of this is converted into useful energy. All systems experience this increase in entropy over time. This is very important to understand and this phenomenon is called the second law of thermodynamics.

Statements of the second law of thermodynamics

Entropy: chance or defect

As you might have guessed, the second law follows the first, commonly referred to as the law of conservation of energy, and states that energy cannot be created and cannot be destroyed. In other words, the amount of energy in the universe or any system is constant. The second law of thermodynamics is commonly referred to as the law of entropy, and it holds that as time passes, energy becomes less useful and its quality decreases over time. Entropy is the degree of randomness or defects that a system has. If the system is very disordered, then it has a large entropy. If there are many faults in the system, then the entropy is low.

In simple terms, the second law of thermodynamics states that the entropy of a system cannot decrease over time. This means that in nature things go from a state of order to a state of disorder. And it's irreversible. The system neverwill become more orderly on its own. In other words, in nature, the entropy of a system always increases. One way to think about it is your home. If you never clean and vacuum it, then pretty soon you will have a terrible mess. Entropy has increased! To reduce it, it is necessary to use energy to use a vacuum cleaner and a mop to clean the surface of dust. The house won't clean itself.

What is the second law of thermodynamics? The formulation in simple words says that when energy changes from one form to another, matter either moves freely, or the entropy (disorder) in a closed system increases. Differences in temperature, pressure, and density tend to level off horizontally over time. Due to gravity, density and pressure do not equalize vertically. The density and pressure at the bottom will be greater than at the top. Entropy is a measure of the spread of matter and energy wherever it has access. The most common formulation of the second law of thermodynamics is mainly associated with Rudolf Clausius, who said:

It is impossible to build a device that does not produce another effect than the transfer of heat from a body with a lower temperature to a body with a higher temperature.

In other words, everything tries to maintain the same temperature over time. There are many formulations of the second law of thermodynamics that use different terms, but they all mean the same thing. Another Clausius statement:

Heat itself is notgoing from a cold to a hotter body.

The second law only applies to large systems. It concerns the likely behavior of a system in which there is no energy or matter. The larger the system, the more likely the second law is.

Another wording of the law:

Total entropy always increases in a spontaneous process.

The increase in entropy ΔS during the course of the process must exceed or be equal to the ratio of the amount of heat Q transferred to the system to the temperature T at which heat is transferred. Formula of the second law of thermodynamics:

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Thermodynamic system

In a general sense, the formulation of the second law of thermodynamics in simple terms states that temperature differences between systems in contact with each other tend to equalize and that work can be obtained from these non-equilibrium differences. But in this case, there is a loss of thermal energy, and the entropy increases. Differences in pressure, density, and temperature in an isolated system tend to equalize if given the opportunity; density and pressure, but not temperature, depend on gravity. A heat engine is a mechanical device that provides useful work due to the difference in temperature between two bodies.

A thermodynamic system is one that interacts and exchanges energy with the area around it. Exchange and transfer must occur in at least two ways. One way should be heat transfer. If athe thermodynamic system "is in equilibrium", it cannot change its state or status without interacting with the environment. Simply put, if you are in balance, you are a "happy system", there is nothing you can do. If you want to do something, you must interact with the outside world.

Formula of the second law of thermodynamics

The second law of thermodynamics: the irreversibility of processes

It is impossible to have a cyclic (repeating) process that completely converts heat into work. It is also impossible to have a process that transfers heat from cold objects to warm objects without using work. Some energy in a reaction is always lost to heat. Also, the system cannot convert all of its energy into work energy. The second part of the law is more obvious.

A cold body cannot heat a warm body. Heat naturally tends to flow from warmer to cooler areas. If heat goes from cooler to warmer it is contrary to what is "natural" so the system has to do some work to make it happen. The irreversibility of processes in nature is the second law of thermodynamics. This is perhaps the most famous (at least among scientists) and important law of all science. One of his formulations:

The entropy of the Universe tends to the maximum.

In other words, entropy either stays the same or gets bigger, the entropy of the Universe can never decrease. The problem is that it's alwaysright. If you take a bottle of perfume and spray it in a room, then soon the fragrant atoms will fill the entire space, and this process is irreversible.

The second law of thermodynamics in simple terms

Relationships in thermodynamics

The laws of thermodynamics describe the relationship between thermal energy or heat and other forms of energy, and how energy affects matter. The first law of thermodynamics states that energy cannot be created or destroyed; the total amount of energy in the universe remains unchanged. The second law of thermodynamics is about the quality of energy. It states that as energy is transferred or converted, more and more usable energy is lost. The second law also states that there is a natural tendency for any isolated system to become more disordered.

Even when order increases in a certain place, when you take into account the whole system, including the environment, there is always an increase in entropy. In another example, crystals may form from a s alt solution when water is evaporated. Crystals are more ordered than s alt molecules in solution; however, evaporated water is much more disordered than liquid water. The process taken as a whole results in a net increase in disorder.

The second law of thermodynamics formulation is simple

Work and energy

The second law explains that it is impossible to convert thermal energy into mechanical energy with 100 percent efficiency. An example can be given withby car. After the process of heating the gas to increase its pressure to drive the piston, there is always some heat left in the gas that cannot be used to perform any additional work. This waste heat must be discarded by transferring it to a radiator. In the case of a car engine, this is done by extracting the spent fuel and air mixture into the atmosphere.

In addition, any device with moving parts creates friction that converts mechanical energy into heat, which is usually unusable and must be removed from the system by transferring it to a radiator. When a hot body and a cold body are in contact with each other, thermal energy will flow from the hot body to the cold body until they reach thermal equilibrium. However, the heat will never return the other way; the temperature difference between two bodies will never spontaneously increase. Moving heat from a cold body to a hot body requires work to be done by an external energy source such as a heat pump.

Irreversibility of processes in nature second law of thermodynamics

The Fate of the Universe

The second law also predicts the end of the universe. This is the ultimate level of disorder, if there is constant thermal equilibrium everywhere, no work can be done and all energy will end up as the random movement of atoms and molecules. According to modern data, the Metagalaxy is an expanding non-stationary system, and there can be no talk of the heat death of the Universe. heat deathis a state of thermal equilibrium at which all processes stop.

This position is erroneous, since the second law of thermodynamics applies only to closed systems. And the universe, as you know, is limitless. However, the very term "heat death of the Universe" is sometimes used to refer to a scenario for the future development of the Universe, according to which it will continue to expand to infinity into the darkness of space until it turns into scattered cold dust.

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