What are the laws of thermodynamics, and the content of the three laws of thermodynamics

The first law of thermodynamics is also known as the law of conservation of energy. The increment of internal energy of a thermodynamic system is equal to the sum of the heat transferred to it from the outside and the work done to it by the outside. (If a system is isolated from the environment, its internal energy will not change.) ）

The second law of thermodynamics is expressed in several ways: Clausius states that heat can be spontaneously transferred from a hotter object to a colder object, but it cannot be spontaneously transferred from a cooler object to a hotter object;

Kelvin-Planck states that it is impossible to draw heat from a single heat source and completely convert that heat into work without other effects.

Entropy Formulation Entropy does not always decrease over time.

The third law of thermodynamics is usually expressed as having zero entropy at absolute zero, perfect crystals of all pure matter. or absolute zero (t=0k, i.e. unattainable.

The first law of thermodynamics is the law of conservation of energy.

The second law of thermodynamics is expressed in several ways: Clausius states that heat can be spontaneously transferred from a hot object to a low temperature object, but it is not possible to spontaneously transfer heat from a low temperature object to a high temperature object; Kelvin-Planck stated that it is impossible to draw heat from a single heat source and completely convert that heat into work without other effects.

The third law of thermodynamics is usually stated that at absolute zero, the entropy of a perfect crystal of all pure matter is zero, or absolute zero (t=0) is unattainable.

There is also the zeroth law of thermodynamics, which states that if each of the two thermodynamic systems is in thermal equilibrium (the same temperature) as the third thermodynamic system, they must also be in thermal equilibrium with each other.

The first law of thermodynamics is the law of conservation of energy.

The second law of thermodynamics is expressed in several ways: Clausius states that heat can be spontaneously transferred from a hot object to a low temperature object, but it is not possible to spontaneously transfer heat from a low temperature object to a high temperature object;

Kelvin-Planck stated that it is impossible to draw heat from a single heat source and completely convert that heat into work without other effects. and the entropy increase formulation: the entropy of an isolated system never decreases.

The third law of thermodynamics is usually stated that at absolute zero, the entropy of a perfect crystal of all pure matter is zero, or absolute zero (t 0k) is unattainable.

NEED NOTICE:

In 1824, the French engineer Sadie Carnot proposed Carnot's theorem. The German Rudolph Clausius and the Englishman Lord Kelvin re-examined Carnot's theorem after the establishment of the first law of thermodynamics, realizing that Carnot's theorem had to be based on a new theorem, the second law of thermodynamics.

They came up with the Clausius formulation and the Kelvin formulation in 1850 and 1851, respectively. These two expressions are conceptually equivalent. Perpetual motion machines that violate the second law of thermodynamics are called perpetual motion machines of the second type.

The Three Laws of Thermodynamics:

1. The first law of thermodynamics is the law of conservation of energy.

Since Joule. The mechanical energy is proved with irrefutable precision and the results of Wang Yuan's test.

After the conversion between electrical energy and internal energy satisfies the conservation relationship, people believe that the law of conservation of energy is a universal basic law of nature.

2. The second law of thermodynamics.

There are several ways to express it:

Clausius formulates that heat can be spontaneously transferred from a hot object to a colder object, but it is not possible to spontaneously transfer heat from a cooler object to a warmer object.

Kelvin. Planck states that it is impossible to draw heat from a single heat source and completely convert that heat into work without exerting other effects.

Entropy formulation: Entropy does not decrease in an isolated system over time.

3. The third law of thermodynamics is usually expressed as absolute zero.

, the entropy of a perfect crystal of all pure matter is zero. or absolute zero (t=0k, i.e. unattainable.

Nohler and Guggenheim also proposed another formulation of the third law of thermodynamics: no system can reduce its temperature to 0k in a finite step, known as the 0k unattainable principle.

Spacecraft, submarines.

The zero, the first were used.

I. II. The Third Law.

The First Law: The first law of thermodynamics is the law of conservation of energy. Ever since Joule proved with irrefutable and precise experimental results that the transformation between mechanical, electrical, and internal energy satisfies the conservation relationship, people have believed that the law of conservation of energy is a universal fundamental law of nature.

The Second Law: Each formulation of the second law of thermodynamics reveals the directionality of macroscopic processes in which a large number of molecules are involved, and makes people realize that the macroscopic processes involving thermal phenomena in nature are directional.

The Third Law: The Third Law of Thermodynamics is usually stated that at absolute zero, the entropy deficit of the perfect crystals of all pure matter is zero, or the absolute zero volt envy return is unattainable.

Law Zero: If two thermodynamic systems are in thermal equilibrium with the third thermodynamic system, then they must also be in thermal equilibrium. That is, the thermal equilibrium is transmitted.