Liter

A liter is a unit of volume that is widely used in everyday life and scientific calculations. It was introduced into the metric system in 1795 by the French Republic, and since then it has become one of the most common units of measurement.

The definition of a liter is based on the volume occupied by 1 kilogram of pure water at a temperature of 4 ° C and normal atmospheric pressure (760 mm Hg). In the system of international units (SI), the liter is called the cubic decimeter. However, if a high degree of accuracy is required, then a value of 1 liter = 1.0000028 dm3 is used.

In approximate calculations, 1 liter is considered equal to 1000 cubic centimeters (cm3), and 1 milliliter (ml) is equal to 1 cm3. This approach, however, meets with some protest from scientists, since this is not an entirely accurate definition.

Liter is widely used in various fields such as science, technology, manufacturing and household needs. It is used to measure the volume of liquids, gases and solids such as oils, gasoline, water, sugar and flour.

Interestingly, the liter is also used as a unit of measurement for the volume of air that the lungs can hold. The capacity of a person's lungs is usually about 6 liters.

In conclusion, the liter is one of the most common units of volume. It is widely used in various fields and is important for scientific and everyday needs. Although its definition is often approximate, the liter remains an important unit of measurement in the metric system.

Liter (Litre) is a unit of volume equal to the volume occupied by 1 kilogram of pure water at a temperature of 4°C and normal atmospheric pressure (760 mm Hg). In the SI system, the liter has the special name cubic decimeter, and this value is not used if a high degree of accuracy is required (1 liter = 1.0000028 dm3). In approximate calculations, 1 liter is taken to be equal to 1000 cubic centimeters (cm3), and 1 milliliter (ml) is taken to be equal to 1 cm3. Currently, this approach faces some protest from scientists.

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**Liter:** historical background and modernity

Humanity is faced with many problems and questions. Among them are large and small. And if some of them can gradually be solved by technical means and the introduction of scientific knowledge into industry, then solving the issue of measuring the volume of liquid is not so simple. The importance of this issue is that volumes are often required to be known for transporting liquid over long distances. But even so, the problem remained pressing. The modern world has long valued ease, accuracy and versatility in use. Time passes, and perhaps soon the liter will define itself even better.

How did it happen that the liter ceased to be the most common unit of measurement of liquid volume? At first glance, the answer is clear - it’s all because of the convenience of switching to standard units of measurement. The fact is, as it became known, previously a unit volume of liquid was called in relation to the volume of a specific product. If it is equal to 2 liters, this is, for example, a barrel. It is important to remember that in addition to having a special measuring cup, you need to know the mass of the contents in order to measure its volume. This is inconvenient, so people began to look for a more universal solution. At the moment, world religions have not yet agreed on what function this unit will perform in the new measurement systems. More than 10 million years ago, people began to not only use a certain unit to measure body volume, but this unit also became a kind of “charisma” that determined the strength of government. However, subsequently, human life improved markedly, and the connection between these two categories weakened. Most likely, this happened precisely because of the development of science, since many people needed to accurately measure the volume of liquid to store a particular liquid in domestic conditions. A liter is a measure of the volume of a certain mass, although the word measure in this case is very imprecise. Most believe that modern measurement systems are accurate. However, the water that fills the smallest planet in the solar system tends to expand when heated. For greater clarity, let’s take prehistoric sand, which now also refers to a dense body, because any objects are inert bodies, they have the property of retaining their size and shape. Much later, in Greece, people discovered the process of evaporation: it is necessary for drying various things. Today, there is a limitation for scientists to investigate the properties of matter at a certain temperature and under pressure - their “imagination” or skill will not help them in this process. First of all, scientists conduct experiments. Until now, in order to determine the boiling point of a liquid at a certain depth, one has to have enormous experience and improve technological measures to preserve it. There is also no scale to determine body volume. And in most cases it is calculated based on the formula - mass of an ideal gas / its molar mass. Which led to the fact that people had to use different ways to measure the volume of liquids, with their own specific measuring cups.