The term "temperature" appeared at a time when physicists thought that warm bodies were composed of more specific substance - caloric - than the same bodies, but cold. And the temperature was interpreted as a value corresponding to the amount of caloric in the body. Since then, the temperature of any body is measured in degrees. But in reality it is a measure of the kinetic energy of moving molecules, and, based on this, it should be measured in Joules, in accordance with the SI system of units.

The concept of "absolute zero temperature" comes from the second law of thermodynamics. According to it, the process of transferring heat from a cold body to a hot one is impossible. This concept was introduced by the English physicist W. Thomson. For achievements in physics, he was granted the noble title of "Lord" and the title of "Baron Kelvin". In 1848, W. Thomson (Kelvin) suggested using a temperature scale, in which he took the absolute zero temperature corresponding to the extreme cold as the starting point, and took degrees Celsius as the division price. The unit of Kelvin is 1/27316 of the temperature of the triple point of water (about 0 degrees C), i.e. temperature at which pure water It is immediately found in three forms: ice, liquid water and steam. temperature is the lowest possible low temperature, at which the movement of molecules stops, and it is no longer possible to extract from the substance thermal energy. Since then, the absolute temperature scale has been named after him.

Temperature is measured on different scales

The most commonly used temperature scale is called the Celsius scale. It is built on two points: on the temperature of the phase transition of water from liquid to vapor and water to ice. A. Celsius in 1742 proposed to divide the distance between reference points into 100 intervals, and take water as zero, while the freezing point is 100 degrees. But the Swede K. Linnaeus suggested doing the opposite. Since then, water freezes at zero degrees A. Celsius. Although it should boil exactly in Celsius. Absolute zero Celsius corresponds to minus 273.16 degrees Celsius.

There are several more temperature scales: Fahrenheit, Réaumur, Rankine, Newton, Roemer. They have different and price divisions. For example, the Réaumur scale is also built on the benchmarks of boiling and freezing of water, but it has 80 divisions. The Fahrenheit scale, which appeared in 1724, is used in everyday life only in some countries of the world, including the USA; one is the temperature of the mixture of water ice - ammonia and the other is the temperature of the human body. The scale is divided into one hundred divisions. Zero Celsius corresponds to 32 The conversion of degrees to Fahrenheit can be done using the formula: F \u003d 1.8 C + 32. Reverse translation: C \u003d (F - 32) / 1.8, where: F - degrees Fahrenheit, C - degrees Celsius. If you are too lazy to count, go to the online Celsius to Fahrenheit conversion service. In the box, type the number of degrees Celsius, click "Calculate", select "Fahrenheit" and click "Start". The result will appear immediately.

Named after the English (more precisely Scottish) physicist William J. Rankin, a former contemporary of Kelvin and one of the founders of technical thermodynamics. There are three important points in his scale: the beginning is absolute zero, the freezing point of water is 491.67 degrees Rankine and the boiling point of water is 671.67 degrees. The number of divisions between the freezing of water and its boiling in both Rankine and Fahrenheit is 180.

Most of these scales are used exclusively by physicists. And 40% of American high school students surveyed these days said they don't know what absolute zero temperature is.

ABSOLUTE ZERO

ABSOLUTE ZERO, the temperature at which all components of the system have the least amount of energy allowed by the laws of QUANTUM MECHANICS; zero on the Kelvin temperature scale, or -273.15 ° C (-459.67 ° Fahrenheit). At this temperature, the entropy of the system - the amount of energy available for doing useful work - is also zero, although total the energy of the system can be different from zero.

Scientific and technical encyclopedic dictionary.

See what "ABSOLUTE ZERO" is in other dictionaries:

Temperature is the minimum temperature limit that a physical body. Absolute zero is the starting point for an absolute temperature scale, such as the Kelvin scale. On the Celsius scale, absolute zero corresponds to a temperature of −273 ... Wikipedia

ABSOLUTE ZERO TEMPERATURE- the origin of the thermodynamic temperature scale; located at 273.16 K (Kelvin) below (see) water, i.e. equal to 273.16 ° C (Celsius). Absolute zero is the lowest temperature in nature and almost unattainable ... Great Polytechnic Encyclopedia

This is the minimum temperature limit that a physical body can have. Absolute zero is the starting point for an absolute temperature scale, such as the Kelvin scale. On the Celsius scale, absolute zero corresponds to a temperature of −273.15 ° C. ... ... Wikipedia

Absolute zero temperature is the minimum temperature limit that a physical body can have. Absolute zero is the starting point for an absolute temperature scale, such as the Kelvin scale. On the Celsius scale, absolute zero corresponds to ... ... Wikipedia

Razg. Neglect An insignificant, insignificant person. FSRYA, 288; BTS, 24; ZS 1996, 33 ...

zero- absolute zero … Dictionary of Russian Idioms

Zero and zero n., m., use. comp. often Morphology: (no) what? zero and zero, why? zero and zero, (see) what? zero and zero, what? zero and zero, about what? about zero, zero; pl. What? zeros and zeros, (no) what? zeros and zeros, why? zeros and zeros, (I see) ... ... Dictionary Dmitrieva

Absolute zero (zero). Razg. Neglect An insignificant, insignificant person. FSRYA, 288; BTS, 24; ZS 1996, 33 To zero. 1. Jarg. they say Shuttle. iron. About severe intoxication. Yuganov, 471; Vakhitov 2003, 22. 2. Jarg. music Exactly, in full accordance with ... ... Big Dictionary Russian sayings

absolute- absolute absurdity absolute authority absolute impeccability absolute disorder absolute fiction absolute immunity absolute leader absolute minimum absolute monarch absolute morality absolute zero ... ... Dictionary of Russian Idioms

Books

Absolute Zero, Absolute Pavel. The life of all the creations of the mad scientist of the nes race is very short. But the next experiment has a chance to exist. What lies ahead for him?...

What is absolute zero (more often - zero)? Does this temperature really exist anywhere in the universe? Can we cool something down to absolute zero in real life? If you're wondering if it's possible to outrun a wave of cold, let's explore the furthest limits of cold temperature...

What is absolute zero (more often - zero)? Does this temperature really exist anywhere in the universe? Can we cool anything down to absolute zero in real life? If you're wondering if it's possible to outrun a wave of cold, let's explore the furthest limits of cold temperature...

Even if you are not a physicist, you are probably familiar with the concept of temperature. Temperature is a measure of the amount of internal random energy in a material. The word "internal" is very important. Throw a snowball, and although the main movement will be quite fast, the snowball will remain quite cold. On the other hand, if you look at air molecules flying around a room, an ordinary oxygen molecule fries at a speed of thousands of kilometers per hour.

We tend to be silent when it comes to technical details, so just for the experts, we note that the temperature is a little more complicated than we said. The true definition of temperature is how much energy you need to expend for each unit of entropy (disorder, if you will). understandable word). But let's skip the subtleties and just focus on the fact that random air or water molecules in the ice will move or vibrate slower and slower as the temperature drops.

Absolute zero is -273.15 degrees Celsius, -459.67 Fahrenheit, and just 0 Kelvin. This is the point where thermal motion stops completely.

Does everything stop?

In the classical consideration of the issue at absolute zero, everything stops, but it is at this moment that a terrible muzzle peeks out from around the corner quantum mechanics. One of the predictions of quantum mechanics that has tainted the blood of no small number of physicists is that you can never measure the exact position or momentum of a particle with perfect certainty. This is known as the Heisenberg uncertainty principle.

If you could cool a sealed room to absolute zero, strange things would happen (more on that in a moment). The air pressure would drop to almost zero, and since air pressure normally opposes gravity, the air would collapse into a very thin layer on the floor.

But even so, if you can measure individual molecules, you'll find something curious: they vibrate and rotate, quite a bit - quantum uncertainty at work. To dot the i's, if you measure the rotation of carbon dioxide molecules at absolute zero, you'll find that oxygen atoms circle carbon at a speed of several kilometers per hour - much faster than you thought.

The conversation comes to a standstill. When we talk about quantum world, the movement loses its meaning. At these scales, everything is defined by uncertainty, so it's not that the particles are stationary, you just can never measure them as if they were stationary.

How low can you fall?

The pursuit of absolute zero essentially meets the same problems as the pursuit of the speed of light. It takes an infinite amount of energy to reach the speed of light, and reaching absolute zero requires an infinite amount of heat to be extracted. Both of these processes are impossible, if anything.

Despite the fact that we have not yet achieved the actual state of absolute zero, we are very close to it (although "very" in this case is a very loose concept; like a children's counting rhyme: two, three, four, four and a half, four on a string, four by a thread, five). The lowest temperature ever recorded on Earth was in Antarctica in 1983, at -89.15 degrees Celsius (184K).

Of course, if you want to cool off like a child, you need to dive into the depths of space. The entire universe is flooded with the remnants of radiation from the Big Bang, in the emptiest regions of space - 2.73 degrees Kelvin, which is slightly colder than the temperature of liquid helium, which we were able to get on Earth a century ago.

But low-temperature physicists are using freeze rays to take technology to the next level. new level. It may surprise you that freeze beams take the form of lasers. But how? Lasers must burn.

That's right, but lasers have one feature - one might even say, an ultimatum: all light is emitted at the same frequency. Ordinary neutral atoms do not interact with light at all unless the frequency is finely tuned. If the atom flies towards the light source, the light receives a Doppler shift and goes to a higher frequency. An atom absorbs less photon energy than it could. So if you set the laser lower, fast moving atoms will absorb light, and emitting a photon in a random direction will lose a little energy on average. If you repeat the process, you can cool the gas down to less than one nanoKelvin, a billionth of a degree.

Everything becomes more extreme. The world record for the coldest temperature is less than one tenth of a billion degrees above absolute zero. Devices that achieve this trap atoms in magnetic fields. "Temperature" depends not so much on the atoms themselves, but on the spin of atomic nuclei.

Now, to restore justice, we need to dream a little. When we usually imagine something frozen to one billionth of a degree, you are sure to get a picture of even air molecules freezing in place. One can even imagine a destructive apocalyptic device that freezes the spins of atoms.

Ultimately, if you really want to experience low temperatures, all you have to do is wait. After about 17 billion years, the radiation background in the Universe will cool down to 1K. In 95 billion years, the temperature will be about 0.01K. In 400 billion years, deep space will be as cold as the coldest experiment on Earth, and even colder after that.

If you're wondering why the universe is cooling so quickly, say thanks to our old friends: entropy and dark energy. The Universe is in the acceleration mode, entering the period exponential growth that will go on forever. Things will freeze very quickly.

What's our business?

All this, of course, is wonderful, and breaking records is also nice. But what's the point? Well, there are many good reasons to understand the lowlands of temperature, and not only as a winner.

The good guys at the National Institute of Standards and Technology, for example, would just like to do cool watch. Time standards are based on things like the frequency of the cesium atom. If the cesium atom moves too much, there is an uncertainty in the measurements, which will eventually cause the clock to malfunction.

But more importantly, especially from a scientific point of view, materials behave insanely at extremely low temperatures. For example, just as a laser is made up of photons that are synchronized with each other - at the same frequency and phase - so the material known as a Bose-Einstein condensate can be created. In it, all atoms are in the same state. Or imagine an amalgam in which each atom loses its individuality and the entire mass reacts as one null super-atom.

At very low temperatures, many materials become superfluid, which means they can be completely viscous, stack in ultrathin layers, and even defy gravity to achieve a minimum of energy. Also at low temperatures, many materials become superconductive, which means they don't have any electrical resistance.

Superconductors are able to respond to external magnetic fields in such a way as to completely cancel them inside the metal. As a result, you can combine the cold temperature and the magnet and get something like levitation.

Why is there an absolute zero but no absolute maximum?

Let's look at the other extreme. If temperature is just a measure of energy, then you can just imagine atoms getting closer and closer to the speed of light. It can't go on indefinitely, can it?

There is a short answer: we don't know. It's entirely possible that there is literally such a thing as an infinite temperature, but if there's an absolute limit, the early universe provides some pretty interesting clues as to what it is. The highest temperature that has ever existed (at least in our universe) probably happened in the so-called "Planck time".

It was a moment 10^-43 seconds long after the Big Bang, when gravity separated from quantum mechanics and physics became exactly what it is now. The temperature at that time was about 10^32 K. That's a septillion times hotter than the inside of our Sun.

Again, we're not at all sure if this is the hottest temperature ever. Because we don't even have big model universe at Planck's time, we're not even sure the universe was boiling to that point. In any case, we are many times closer to absolute zero than to absolute heat.

- 48.67 Kb

Federal State Budgetary Educational Institution of Higher Professional Education

"Voronezh State Pedagogical University"

Department of General Physics

on the topic: "Absolute zero temperature"

Completed by: 1st year student, FMF,

PI, Kondratenko Irina Aleksandrovna

Checked by: Assistant of the Department of General

physicists Afonin G.V.

Voronezh-2013

Introduction………………………………………………………. 3

1.Absolute zero…………………………………………...4

2.History………………………………………………………… 6

3. Phenomena observed near absolute zero………..9

Conclusion……………………………………………………… 11

List of used literature…………………………..12

Introduction

For many years, researchers have been attacking the absolute zero temperature. As you know, the temperature equal to absolute zero characterizes the ground state of a system of many particles - the state with the lowest possible energy, at which atoms and molecules perform the so-called "zero" vibrations. Thus, deep cooling close to absolute zero (it is believed that absolute zero itself is unattainable in practice) opens up unlimited possibilities for studying the properties of matter.

1. Absolute zero

Absolute zero temperature (more rarely - absolute zero temperature) is the minimum temperature limit that a physical body in the Universe can have. Absolute zero serves as the reference point for an absolute temperature scale, such as the Kelvin scale. In 1954, the X General Conference on Weights and Measures established a thermodynamic temperature scale with one reference point - the triple point of water, the temperature of which is taken to be 273.16 K (exactly), which corresponds to 0.01 ° C, so that on the Celsius scale absolute zero corresponds to temperature -273.15°C.

In the framework of the applicability of thermodynamics, absolute zero is unattainable in practice. Its existence and position on the temperature scale follows from the extrapolation of the observed physical phenomena, while such extrapolation shows that at absolute zero, the energy of the thermal motion of molecules and atoms of a substance must be equal to zero, that is, the chaotic motion of particles stops, and they form an ordered structure, occupying a clear position in the nodes of the crystal lattice (liquid helium is an exception). However, from the point of view of quantum physics, even at absolute zero temperature, there are zero fluctuations, which are due to the quantum properties of particles and the physical vacuum surrounding them.

As the temperature of the system tends to absolute zero, its entropy, heat capacity, thermal expansion coefficient also tend to zero, and the chaotic motion of the particles that make up the system stops. In a word, matter becomes supersubstance with superconductivity and superfluidity.

The absolute zero temperature is unattainable in practice, and obtaining temperatures approaching it as close as possible is a complex experimental problem, but temperatures have already been obtained that are only millionths of a degree away from absolute zero. .

Let us find the value of absolute zero on the Celsius scale by equating the volume V to zero and taking into account that

Hence the absolute zero temperature is -273°C.

This is the limiting, lowest temperature in nature, that “greatest or last degree of cold”, the existence of which Lomonosov predicted.

Fig.1. Absolute scale and Celsius scale

The SI unit of absolute temperature is called the kelvin (abbreviated as K). Therefore, one degree Celsius is equal to one degree Kelvin: 1 °C = 1 K.

Thus, the absolute temperature is a derivative quantity that depends on the Celsius temperature and on the experimentally determined value of a. However, it is of fundamental importance.

From the point of view of molecular kinetic theory absolute temperature is related to the average kinetic energy of the random motion of atoms or molecules. At T = 0 K, the thermal motion of molecules stops.

2. History

The physical concept of "absolute zero temperature" is very important for modern science. importance: such a concept as superconductivity is closely connected with it, the discovery of which made a splash in the second half of the 20th century.

To understand what absolute zero is, one should refer to the works of such famous physicists as G. Fahrenheit, A. Celsius, J. Gay-Lussac and W. Thomson. They are the ones who played key role in the creation of the basic temperature scales still in use today.

The first to offer his own temperature scale in 1714 was the German physicist G. Fahrenheit. At the same time, the temperature of the mixture, which included snow and ammonia, was taken as absolute zero, that is, the lowest point on this scale. The next important indicator was normal temperature the human body, which began to equal 1000. Accordingly, each division of this scale was called the “degree Fahrenheit”, and the scale itself was called the “Fahrenheit scale”.

After 30 years, the Swedish astronomer A. Celsius proposed his own temperature scale, where the main points were the melting temperature of ice and the boiling point of water. This scale was called the "Celsius scale", it is still popular in most countries of the world, including Russia.

In 1802, while conducting his famous experiments, the French scientist J. Gay-Lussac discovered that the volume of a gas mass at constant pressure is directly dependent on temperature. But the most curious thing was that when the temperature changed by 10 Celsius, the volume of the gas increased or decreased by the same amount. Having made the necessary calculations, Gay-Lussac found that this value was equal to 1/273 of the volume of gas. From this law, the obvious conclusion followed: the temperature equal to -273 ° C is the lowest temperature, even approaching which it is impossible to reach it. This temperature is called "absolute zero temperature". Moreover, absolute zero became the starting point for creating the absolute temperature scale, in which the English physicist W. Thomson, also known as Lord Kelvin, took an active part. His main research concerned the proof that no body in nature can be cooled below absolute zero. At the same time, he actively used the second law of thermodynamics, therefore, introduced by him in 1848 absolute scale temperature became known as the thermodynamic or "Kelvin scale". In subsequent years and decades, only a numerical refinement of the concept of "absolute zero" took place.

Fig.2. Relationship between Fahrenheit (F), Celsius (C) and Kelvin (K) temperature scales.

It is also worth noting that absolute zero plays a very important role in the SI system. The thing is that in 1960 at the next General Conference on Weights and Measures, the unit of thermodynamic temperature - kelvin - became one of the six basic units of measurement. At the same time, it was specifically stipulated that one degree Kelvin

is numerically equal to one degree Celsius, only here the reference point "according to Kelvin" is considered to be absolute zero.

Basic physical meaning absolute zero lies in the fact that, according to the basic physical laws, at such a temperature, the energy of motion of elementary particles, such as atoms and molecules, is equal to zero, and in this case, any chaotic motion of these same particles should stop. At a temperature equal to absolute zero, atoms and molecules should take a clear position in the main points of the crystal lattice, forming an ordered system.

Currently, using special equipment, scientists have been able to obtain a temperature only a few millionths higher than absolute zero. It is physically impossible to achieve this value itself because of the second law of thermodynamics.

3. Phenomena observed near absolute zero

At temperatures close to absolute zero, purely quantum effects can be observed at the macroscopic level, such as:

1. Superconductivity - the property of some materials to have strictly zero electrical resistance when they reach a temperature below a certain value (critical temperature). Several hundreds of compounds, pure elements, alloys and ceramics are known that pass into the superconducting state.

Superconductivity is a quantum phenomenon. It is also characterized by the Meissner effect, which consists in the complete displacement of the magnetic field from the bulk of the superconductor. The existence of this effect shows that superconductivity cannot be described simply as ideal conductivity in the classical sense. Opening in 1986-1993 a number of high-temperature superconductors (HTSCs) pushed far the temperature limit of superconductivity and allowed the practical use of superconducting materials not only at the temperature of liquid helium (4.2 K), but also at the boiling point of liquid nitrogen (77 K), a much cheaper cryogenic liquid.

2. Superfluidity - the ability of a substance in a special state (quantum liquid), which occurs when the temperature drops to absolute zero (thermodynamic phase), to flow through narrow slots and capillaries without friction. Until recently, superfluidity was known only for liquid helium, but in last years superfluidity was also discovered in other systems: in rarefied atomic Bose condensates, solid helium.

Superfluidity is explained as follows. Since helium atoms are bosons, quantum mechanics allows an arbitrary number of particles to be in the same state. Near absolute zero temperatures, all helium atoms are in the ground energy state. Since the energy of the states is discrete, an atom can receive not any energy, but only one that is equal to the energy gap between adjacent energy levels. But at low temperatures, the collision energy may be less than this value, as a result of which energy dissipation simply will not occur. The fluid will flow without friction.

3. Bose - Einstein condensate - state of aggregation a substance based on bosons cooled to temperatures close to absolute zero (less than a millionth of a degree above absolute zero). In such a strongly cooled state, a sufficiently large number of atoms find themselves in their minimum possible quantum states, and quantum effects begin to manifest themselves at the macroscopic level.

Conclusion

The study of the properties of matter near absolute zero is of great interest to science and technology.

Many properties of a substance, veiled at room temperature by thermal phenomena (for example, thermal noise), begin to manifest themselves more and more as the temperature decreases, allowing one to study in its pure form the patterns and relationships inherent in a given substance. Research in the field of low temperatures made it possible to discover many new natural phenomena, such as, for example, the superfluidity of helium and the superconductivity of metals.

At low temperatures, the properties of materials change dramatically. Some metals increase their strength, become ductile, others become brittle, like glass.

The study of physicochemical properties at low temperatures will make it possible in the future to create new substances with predetermined properties. All this is very valuable for the design and construction of spacecraft, stations and instruments.

It is known that during radar studies of cosmic bodies, the received radio signal is very small and it is difficult to distinguish it from various noises. Molecular oscillators and amplifiers recently created by scientists operate at very low temperatures and therefore have a very low noise level.

Low temperature electrical and magnetic properties metals, semiconductors and dielectrics make it possible to develop fundamentally new radio engineering devices of microscopic dimensions.

Extremely low temperatures are used to create the vacuum required, for example, for the operation of giant nuclear particle accelerators.

Bibliography

http://wikipedia.org
http://rudocs.exdat.com
http://fb.ru

Short description

Absolute zero temperature

The limiting temperature at which the volume of an ideal gas becomes zero is taken as absolute zero temperature.

Let's find the value of absolute zero on the Celsius scale.
Equating volume V in formula (3.1) to zero and taking into account that

Hence the absolute zero temperature is

t= -273 °С. 2

This is the limiting, lowest temperature in nature, that “greatest or last degree of cold”, the existence of which Lomonosov predicted.

The highest temperatures on Earth - hundreds of millions of degrees - were obtained during explosions thermonuclear bombs. Even more high temperatures characteristic of the inner regions of some stars.

2More exact value absolute zero: -273.15 °С.

Kelvin scale

The English scientist W. Kelvin introduced absolute scale temperatures. Zero temperature on the Kelvin scale corresponds to absolute zero, and the unit of temperature on this scale is equal to degrees Celsius, so the absolute temperature T is related to temperature on the Celsius scale by the formula

T = t + 273. (3.2)

On fig. 3.2 shows the absolute scale and the Celsius scale for comparison.

The SI unit of absolute temperature is called kelvin(abbreviated as K). Therefore, one degree Celsius equals one degree Kelvin:

Thus, the absolute temperature, according to the definition given by formula (3.2), is a derivative quantity that depends on the Celsius temperature and on the experimentally determined value of a.

Reader: What is the physical meaning of absolute temperature?

We write expression (3.1) in the form

Given that the temperature on the Kelvin scale is related to the temperature on the Celsius scale by the ratio T = t + 273, we get

Where T 0 = 273 K, or

Since this relation is valid for an arbitrary temperature T, then the Gay-Lussac law can be formulated as follows:

For a given mass of gas at p = const, the relation

Task 3.1. At a temperature T 1 = 300 K gas volume V 1 = 5.0 l. Determine the volume of gas at the same pressure and temperature T= 400 K.

STOP! Decide for yourself: A1, B6, C2.

Task 3.2. With isobaric heating, the volume of air increased by 1%. By what percent did the absolute temperature increase?

= 0,01.

Answer: 1 %.

Remember the resulting formula

STOP! Decide for yourself: A2, A3, B1, B5.

Charles' law

The French scientist Charles experimentally found that if you heat a gas so that its volume remains constant, then the pressure of the gas will increase. The dependence of pressure on temperature has the form:

R(t) = p 0 (1 + b t), (3.6)

Where R(t) is pressure at temperature t°C; R 0 – pressure at 0 °C; b is the temperature coefficient of pressure, which is the same for all gases: 1/K.

Reader: Surprisingly, the temperature coefficient of pressure b is exactly equal to the temperature coefficient of volumetric expansion a!

Let us take a certain mass of gas with a volume V 0 at temperature T 0 and pressure R 0 . For the first time, keeping the pressure of the gas constant, we heat it to a temperature T 1 . Then the gas will have volume V 1 = V 0 (1 + a t) and pressure R 0 .

The second time, keeping the volume of the gas constant, we heat it to the same temperature T 1 . Then the gas will have pressure R 1 = R 0 (1 + b t) and volume V 0 .

Since the gas temperature is the same in both cases, the Boyle–Mariotte law is valid:

p 0 V 1 = p 1 V 0 Þ R 0 V 0 (1 + a t) = R 0 (1 + b t)V 0 Þ

Þ 1 + a t = 1+b tÞ a = b.

So there is nothing surprising in the fact that a = b, no!

Let us rewrite Charles's law in the form

Given that T = t°С + 273 °С, T 0 \u003d 273 ° С, we get