The history of the thermometer. Report: Temperature Scales and Thermometers

CONTENT:    PHYSICS REPORT ON THEM: TEMPERATURE SCALES, THERMOMETERS AND THEIR INVENTORS Temperature scales. There are several graded temperature scales, and freezing and boiling points of water are usually taken as reference points. Now the most common in the world is the Celsius scale. In 1742, the Swedish astronomer Anders Celsius proposed a 100-degree thermometer scale, in which the boiling point of water at normal atmospheric pressure is taken as 0 degrees, and the melting of ice is at 100 degrees.

Scale Reumura, today almost abandoned. To make the measurement independent of thermometer traces, such as boiling point or freezing water, William Thomson proposed the concept of absolute temperature. This is an absolute zero, a virtual limit, which we now know very closely.

At absolute zero, the particles that make up the matter would be in a state of complete rest. In this case, the method of wet finger acting on the air, keeps its followers. Although sensations of heat and cold are an integral part of human experience, many scientific minds occupy accurate temperature measurements, and it is unclear whether the ancient Greeks or Chinese had a means of measuring temperature, but this is what the history of temperature sensors begins to write in the Renaissance.

PHYSICAL REPORT

TEMPERATURE SCALES, THERMOMETERS

AND THEIR INVENTORS

Temperature Scales. There are several graded temperature scales, and freezing and boiling points of water are usually taken as reference points. Now the most common in the world is the Celsius scale. In 1742, the Swedish astronomer Anders Celsius proposed a 100-degree thermometer scale, in which the boiling point of water at normal atmospheric pressure is taken as 0 degrees, and the melting of ice is at 100 degrees. The scale division is 1/100 of this difference. When they began to use thermometers, it turned out to be more convenient to swap 0 and 100 degrees. Perhaps Carl Linney took part in this (he taught medicine and natural science at the same Uppsala University, where Celsius is astronomy), who in 1838 proposed to take the ice melting temperature at 0 temperature, but did not seem to have thought of the second reference point. To date, the Celsius scale has changed somewhat: the temperature of ice melting at normal pressure, which is not very dependent on pressure, is still assumed to be at 0 ° C. But the boiling point of water at atmospheric pressure is now 99.975 ° C, which does not affect the measurement accuracy of almost all thermometers, except for special precision thermometers. The temperature scales of Fahrenheit, Kelvin, Reaumur and others are also known. The temperature scale of Fahrenheit (in the second variant adopted since 1714) has three fixed points: 0 ° corresponded to the temperature of a mixture of water, ice and ammonia, 96 ° - the body temperature of a healthy person ( under the arm or mouth). As a reference temperature for the verification of various thermometers, a value of 32 ° was taken for the melting point of ice. The Fahrenheit scale is widespread in English-speaking countries, but it is almost never used in scientific literature. For converting Celsius temperature (С) to Fahrenheit temperature (температурыF), there is a formula F = (9/5) C + 32, and for reverse translation - the formula C = (5/9) (F 32). Both scales, both Fahrenheit and Celsius, are very inconvenient when conducting experiments under conditions where the temperature drops below the freezing point of water and is expressed by a negative number. For such cases, absolute temperature scales were introduced, which are based on extrapolation to the so-called absolute zero — the point at which the molecular movement should stop. One of them is called the Rankine scale, and the other is the absolute thermodynamic scale; temperatures are measured in degrees Rankin (Rа) and Kelvin (K). Both scales begin at an absolute zero temperature, and the freezing point of water corresponds to 491.7 R and 273.16 K. The number of degrees and kelvins between the freezing point and boiling point of water on the Celsius scale and the absolute thermodynamic scale are the same and equal to 100; for the Fahrenheit and Rankin scales, it is also the same, but it is 180. Degrees Celsius are converted to Kelvin using the formula K = C + 273.16, and degrees Fahrenheit are converted to degrees Rankin using the formula R = F + 459.7. In Europe, the Reaumur scale, introduced in 1730 by Rene Antoine de Reaumure, was distributed for a long time. It is not built arbitrarily, like the Fahrenheit scale, but in accordance with the thermal expansion of alcohol (in the ratio of 1000: 1080). 1 degree of Reaumur is equal to 1/80 of the temperature interval between the melting points of ice (0 ° R) and boiling water (80 ° R), i.e. 1 ° R = 1.25 ° C, 1 ° C = 0.8 ° R., But currently out of use.

Why take measurements?

Heat is a measure of energy in a body or material; the higher the energy, the more heat. However, unlike the physical properties of mass and length, it is difficult to measure. Most indirect methods were based on observing the effect of heat on the object and deriving temperature.

At the same time, Ole Römer defined two fixed points, and then an interpolation between these two points, the selected points were Hooke’s freezing point and boiling water point. This puzzle was solved by scientists, including Gay-Lussac, who worked on the laws of gas.

After the introduction of the International System of Units (SI), two temperature scales are recommended for use. The first scale is thermodynamic, which does not depend on the properties of the substance used (working medium) and is introduced through the Carnot cycle. The unit of temperature in this temperature scale is one kelvin (1 K) - one of the basic units in the SI system. This unit is named after the English physicist William Thomson (Lord Kelvin), who developed this scale and kept the unit of temperature measurement the same as on the Celsius temperature scale. The second recommended temperature scale is international practical. This scale has 11 reference points — the phase transition temperatures of a number of pure substances, and the values ​​of these temperature points are constantly being refined. The unit of temperature measurement in the international practical scale is also 1 K.

Dilation observation: liquids and bimetals

Gallil's design of a device with varying temperature dates back to the time when He relied on compressing air in a vessel to install a column of water, the height of which indicates the degree of cooling. However, the effect of air pressure is very large, and this device was not a major discovery.

He sealed the glass tube containing the liquid and observed the displacement of the liquid during its expansion. The scale on the tube contributed to the reading of evolution, but the system did not have exact units. Collaboration between Romer and Daniel Gabriel Fahrenheit. Daniel Gabriel Fahrenheit began producing thermometers with alcohol and mercury, which is ideal because it responds linearly to temperature changes over a wide range, although its toxicity limits its use. now replace mercury. A liquid thermometer is widely distributed, although it is important to control the depth of the flask.

Currently, the main reference point of both the thermodynamic scale and the international practical temperature scale is the triple point of water. This point corresponds to strictly defined values ​​of temperature and pressure at which water can simultaneously exist in solid, liquid and gaseous states. Moreover, if the state of the thermodynamic system is determined only by the values ​​of temperature and pressure, then the triple point can be only one. In the SI system, the temperature of the triple point of water is assumed to be 273.16 K at a pressure of 609 Pa.

Using a thermometric sensor ensures good heat transfer. It is based on the differential expansion of two interconnected metal strips. Temperature changes create a bend that activates a thermostat or sensor, similar to devices installed in gas grills.

Accuracy is low, plus or minus 2 degrees, but these sensors are economical and have many uses.





At the beginning of the 19th century, electricity was fascinated by many researchers, who quickly discovered that the resistance and conductivity of metals are variable. Peltier discovered that this thermocouple effect is reversible and can be used for cooling.

In addition to setting reference points determined by the temperature standard, it is necessary to choose the thermodynamic property of the body, which is described by a physical quantity, the change of which is a sign of a change in temperature or a thermometric sign. This property should be fairly easily reproducible, and the physical quantity - easily measured. Measurement of the specified physical quantity allows to obtain a set of temperature points (and the corresponding temperature values), intermediate with respect to the reference points.

In the same year, Humphry Davy demonstrated that the resistivity of a metal is related to temperature. This detector measures the electrical resistance of a length of platinum wire and is widely regarded as the most accurate instrument. The 20th century was also marked by the invention of semiconductor temperature measuring devices. They accurately respond to changes in temperature, but until recently did not have linearity.

Samuel Langley Very hot and molten metals dissipate heat and visible light. Nobili was able to detect this radiated energy by connecting thermocouples in series with the formation of a thermoelectric cell. The bolometer was discovered by the American Samuel Langley, the bolometer is the arrangement of two platinum bands, one of which turned black, in accordance with the structure of the Wheatstone bridge. Infrared radiation has led to a measurable change in resistance.

The ratio of the temperature scale Fahrenheit and Celsius

fahrenheit scale Celsius scale

Boiling point 212 ° 100 °

32 ° 0 ° freezing point

Temperature of absolute zero -459.67 ° -273.15 °

When converting from Fahrenheit to Celsius, subtract 32 from the original number and multiply by 5/9.

When converting from Celsius to Fahrenheit, the original number is multiplied by 9/5 and added 32.

In contrast, photon detectors created in the 1940s react only to infrared radiation with a limited wavelength. Lead sulphide detectors are sensitive to wavelengths of up to 3 microns. Lord Kelvin Fahrenheit felt the need to develop a temperature scale when he was making thermometers.

A quarter of a century later, Anders Celsius proposed a scale from 0 to 100, which now bears his name. Noting the advantages of a fixed point at one end of the scale, William Thomson, later known as Lord Kevin, suggested using zero abs as the starting point of the Celsius system. This is how the Kelvin scale was used in the scientific field.

Thermometers. German Gabriel Daniel Fahrenheit made a decisive contribution to the development of the design of thermometers. In 1709 he invented an alcohol thermometer, and in 1714 - a mercury thermometer. He gave them the same form that applies now. The success of his thermometers should be sought in the new method of purifying mercury introduced by him; In addition, before soldering, he boiled the liquid in the tube.

A copy is available to readers who want to deepen their knowledge in units of measurement. The part of physics that studies thermal phenomena, i.e. phenomena in which temperature and heat are critical. Temperature A physical size that expresses the thermal state of a system and describes its ability to exchange heat with the environment or other bodies. When two systems are placed in thermal contact, heat flows from the system to a higher temperature than the temperature below until reaching thermal equilibrium, where the two systems are at the same temperature. The concept of temperature is related to the idea of ​​providing a relative assessment of how the bodies are cold or hot to the touch. Therefore, the terms temperature and heat are correlated, but refer to different concepts: temperature is a property of the body, Heat is a form of energy that flows from one body to another to fill the temperature difference. Indirect methods based on the effects of heating or cooling are commonly used to obtain temperature measurements, the most commonly used method is dilatation measurement. A mercury thermometer measures the volume change of mercury placed in a glass capillary when it is brought into contact with a body of unknown temperature. The elongation of a mercury column is proportional to the body temperature. If the heat drops to an ideal gas contained in a vessel with a fixed volume, the temperature rise can be calculated by measuring the pressure change in the vessel. Temperature Scales. One of the first temperature scales was studied by the German physicist Gabriel Daniel Fahrenheit. However, in the scientific field absolute scale or Kelvin is invented by the British mathematician and physicist William Thomson Kelvin. The corresponding Rank rank is used mainly in landscapes. Page 1 of 4. Physics - Basic facts about temperature and its properties.

Rene Antoine de Reaumur did not approve of mercury use in thermometers due to the low coefficient of expansion of mercury. In 1730, he proposed to use alcohol in thermometers, as well. In 1731 he invented a water-alcohol thermometer. And since Reomur found that the alcohol used by him, mixed in a ratio of 5: 1 with water, expands in a ratio of 1000: 1080 as the temperature changes from freezing to boiling point of water, he suggested a scale from 0 to 80 °.

Calorimeter: laboratory experience

Physics. Measure the water equivalent of the calorimeter and measure the specific heat of the substance. If it had remained with Anders Tselis’s original idea about the České science, the current outdoor temperature would have been a hundred degrees. And the water below zero will not be cold, but will cook.

In the middle of the century, when it came from one hundred to zero, the temperature of a person was somehow on this Friday - and this was not without jumps. The first thermoscopes appeared at the end of the century, and a number of sciences joined their design. The most famous of these is the astronomer Galileo Galilei, whose version refers to the period of the temperature probe. It was a simple instrument: a glass tube closed on one side of the bay.

Scientists. Anders Celsius. Anders Celsius was born on November 27, 1701 in Sweden. His areas of interest: astronomy, general physics, geophysics.

He taught astronomy at Uppsala University, founded an astronomical observatory there.

Celsius first measured the brightness of stars, established the relationship between the northern lights and vibrations in the Earth’s magnetic field.

The pipe was inserted into the water and, depending on the ambient temperature, the water fell or rose. A place for water was used, as well as wine. However, such a crime suffers from a distortion of atmospheric pressure. However, thermoscopes missed a single scale that could read how warm or cold it was. At some point there were fifteen different scales. Only two of the Cesium and Fahrenheit scale met scatter.

And the German physicist Daniel Gabriel Fahrenheit built the first modern thermometer. The same Fahrenheit over the next fifteen years came with a standard scale, where hundreds did not indicate the boiling point of water, but the natural body temperature. Point shoes were 32 and 212 degrees. Today, its scale is equipped with thermometers in only a few parts of the world, in most countries it shows temperatures in degrees Celsius.

He took part in the Lapland expedition of 1736-1737 to measure the meridian. Upon returning from the polar regions, Celsius began active work on the organization and construction of the astronomical observatory in Uppsala and in 1740 became its director. Anders Celsius died March 25, 1744.

The mineral named Celsins is named after it - a kind of barium feldspar.

Thermometers are devices for measuring ambient temperature or specific objects. They can be divided according to the principle of work. In gas thermometers, temperature and temperature shrinkage is a gas, its variations are measured. parameters, for example, volume. Thermometers for steam use the dependence of vapor pressure on its temperature, which are often used in automotive thermostats. A resistance thermometer is based on the dependence of electrical resistance on conductor temperature, where platinum and thermocouples are temperature sensors based on the Seebeck phenomenon, i.e. the presence of an electromotive force due to temperature changes at the border of two different metals. They are highly accurate and reliable. They are used in engineering and science. Magnetic thermometers use a close relationship between the magnetic susceptibility of certain substances and their temperature. They are very useful in some areas of technology, as they also allow the measurement of zero absolute Kelvin zeros.

  • Liquid thermometers - using the phenomenon of thermal expansion of the liquid.
  • Typical examples are mercury and alcohol thermometers.
In terms of use, temperature sensors are further subdivided into.

Gabriel Fahrenheit. Daniel Gabriel Fahrenheit (1686–1736) - German physicist. Born May 24, 1686 in Danzig (now Gdansk, Poland). He studied physics in Germany, Holland and England. Almost all his life he lived in Holland, where he was engaged in the manufacture of accurate meteorological instruments. In 1709 he made an alcohol, in 1714 - a mercury thermometer, using a new method of purifying mercury. For a mercury thermometer, Fahrenheit built a scale with three reference points: 0 ° corresponded to the water – ice – ammonia mixture temperature, 96 ° to the body temperature of a healthy person, and 32 ° for the ice melting point was taken as the reference temperature. The boiling point of pure water on the Fahrenheit scale was 212 °. The Fahrenheit scale is used in many English-speaking countries, although it gradually gives way to the Celsius scale. In addition to the manufacture of thermometers, Fahrenheit was engaged in the improvement of barometers and hygrometers. He also investigated the dependence of the change in the boiling point of a liquid on the atmospheric pressure and the salt content in it, discovered the phenomenon of supercooling of water, and compiled the tables of specific gravities of bodies. Fahrenheit died in the Hague on September 16, 1736.

Rene Reaumur. Rene Antoine de Reaumur (Rene Antoin de Reaumur) was born on February 28, 1683 in La Rochelle, a French naturalist, foreign honorary member of the St. Petersburg Academy of Sciences (1737). Works on regeneration, physiology, biology of colonies of insects. He proposed a temperature scale, named after him. He perfected some methods of steel preparation; one of the first attempts were made to scientifically substantiate some of the casting processes; he wrote the work The Art of Transforming Iron into Steel. He came to a valuable conclusion, iron, steel, cast iron, differ in the amount of some impurity and by adding this admixture to iron, by cementation or fusing with iron Reomur received steel. In 1814, K. Careten proved that carbon is an impurity.

Reaumur gave a method of making frosted glass.

Today, memory connects his name only with the invention of a long-used temperature scale. In fact, Rene Antoine Ferschant de Reaumure, who lived in 1683-1757, mainly in Paris, belonged to those scientists whose universality in our time - the time of narrow specialization - is difficult to imagine. Reaumur was simultaneously a technician, physicist and naturalist. He gained great fame outside France as an entomologist. In the last years of his life, Reaumur came to the idea that the search for the mysterious transforming power should be conducted in those places where its manifestation is most obvious - when transforming food in the body, i.e. with her assimilation.

William Rankin. William John Macquarne Rankin (William John M. Rankine) (1820-72), Scottish engineer and physicist, one of the creators of technical thermodynamics. He proposed a theoretical steam engine cycle (Rankin cycle), a temperature scale (Rankin scale), the zero of which coincides with zero thermodynamic temperature, and in size 1 degree R. (° R) is 5/9 K (the scale is not widespread).

PHYSICAL REPORT

TEMPERATURE SCALES, THERMOMETERS

AND THEIR INVENTORS

Temperature Scales. There are several graded temperature scales, and freezing and boiling points of water are usually taken as reference points. Now the most common in the world is the Celsius scale. In 1742, the Swedish astronomer Anders Celsius proposed a 100-degree thermometer scale, in which the boiling point of water at normal atmospheric pressure is taken as 0 degrees, and the melting of ice is at 100 degrees. The scale division is 1/100 of this difference. When they began to use thermometers, it turned out to be more convenient to swap 0 and 100 degrees. Perhaps Carl Linney took part in this (he taught medicine and natural science at the same Uppsala University, where Celsius is astronomy), who in 1838 proposed to take the ice melting temperature at 0 temperature, but did not seem to have thought of the second reference point. To date, the Celsius scale has changed somewhat: the temperature of ice melting at normal pressure, which is not very dependent on pressure, is still assumed to be at 0 ° C. But the boiling point of water at atmospheric pressure is now 99.975 ° C, which does not affect the measurement accuracy of almost all thermometers, except for special precision thermometers. The temperature scales of Fahrenheit, Kelvin, Reaumur and others are also known. The temperature scale of Fahrenheit (in the second variant adopted since 1714) has three fixed points: 0 ° corresponded to the temperature of a mixture of water, ice and ammonia, 96 ° - the body temperature of a healthy person ( under the arm or mouth). As a reference temperature for the verification of various thermometers, a value of 32 ° was taken for the melting point of ice. The Fahrenheit scale is widespread in English-speaking countries, but it is almost never used in scientific literature. For converting Celsius temperature (С) to Fahrenheit temperature (температурыF), there is a formula F = (9/5) C + 32, and for reverse translation - the formula C = (5/9) (F 32). Both scales, both Fahrenheit and Celsius, are very inconvenient when conducting experiments under conditions where the temperature drops below the freezing point of water and is expressed by a negative number. For such cases, absolute temperature scales were introduced, which are based on extrapolation to the so-called absolute zero — the point at which the molecular movement should stop. One of them is called the Rankine scale, and the other is the absolute thermodynamic scale; temperatures are measured in degrees Rankin (Rа) and Kelvin (K). Both scales begin at an absolute zero temperature, and the freezing point of water corresponds to 491.7 R and 273.16 K. The number of degrees and kelvins between the freezing point and boiling point of water on the Celsius scale and the absolute thermodynamic scale are the same and equal to 100; for the Fahrenheit and Rankin scales, it is also the same, but it is 180. Degrees Celsius are converted to Kelvin using the formula K = C + 273.16, and degrees Fahrenheit are converted to degrees Rankin using the formula R = F + 459.7. In Europe, the Reaumur scale, introduced in 1730 by Rene Antoine de Reaumure, was distributed for a long time. It is not built arbitrarily, like the Fahrenheit scale, but in accordance with the thermal expansion of alcohol (in the ratio of 1000: 1080). 1 degree of Reaumur is equal to 1/80 of the temperature interval between the melting points of ice (0 ° R) and boiling water (80 ° R), i.e. 1 ° R = 1.25 ° C, 1 ° C = 0.8 ° R., But currently out of use.

After the introduction of the International System of Units (SI), two temperature scales are recommended for use. The first scale is thermodynamic, which does not depend on the properties of the substance used (working medium) and is introduced through the Carnot cycle. The unit of temperature in this temperature scale is one kelvin (1 K) - one of the basic units in the SI system. This unit is named after the English physicist William Thomson (Lord Kelvin), who developed this scale and kept the unit of temperature measurement the same as on the Celsius temperature scale. The second recommended temperature scale is international practical. This scale has 11 reference points — the phase transition temperatures of a number of pure substances, and the values ​​of these temperature points are constantly being refined. The unit of temperature measurement in the international practical scale is also 1 K.

Dilation observation: liquids and bimetals

Gallil's design of a device with varying temperature dates back to the time when He relied on compressing air in a vessel to install a column of water, the height of which indicates the degree of cooling. However, the effect of air pressure is very large, and this device was not a major discovery.

He sealed the glass tube containing the liquid and observed the displacement of the liquid during its expansion. The scale on the tube contributed to the reading of evolution, but the system did not have exact units. Collaboration between Romer and Daniel Gabriel Fahrenheit. Daniel Gabriel Fahrenheit began producing thermometers with alcohol and mercury, which is ideal because it responds linearly to temperature changes over a wide range, although its toxicity limits its use. now replace mercury. A liquid thermometer is widely distributed, although it is important to control the depth of the flask.

Currently, the main reference point of both the thermodynamic scale and the international practical temperature scale is the triple point of water. This point corresponds to strictly defined values ​​of temperature and pressure at which water can simultaneously exist in solid, liquid and gaseous states. Moreover, if the state of the thermodynamic system is determined only by the values ​​of temperature and pressure, then the triple point can be only one. In the SI system, the temperature of the triple point of water is assumed to be 273.16 K at a pressure of 609 Pa.

Using a thermometric sensor ensures good heat transfer. It is based on the differential expansion of two interconnected metal strips. Temperature changes create a bend that activates a thermostat or sensor, similar to devices installed in gas grills.

Accuracy is low, plus or minus 2 degrees, but these sensors are economical and have many uses.





At the beginning of the 19th century, electricity was fascinated by many researchers, who quickly discovered that the resistance and conductivity of metals are variable. Peltier discovered that this thermocouple effect is reversible and can be used for cooling.

In addition to setting reference points determined by the temperature standard, it is necessary to choose the thermodynamic property of the body, which is described by a physical quantity, the change of which is a sign of a change in temperature or a thermometric sign. This property should be fairly easily reproducible, and the physical quantity - easily measured. Measurement of the specified physical quantity allows to obtain a set of temperature points (and the corresponding temperature values), intermediate with respect to the reference points.

In the same year, Humphry Davy demonstrated that the resistivity of a metal is related to temperature. This detector measures the electrical resistance of a length of platinum wire and is widely regarded as the most accurate instrument. The 20th century was also marked by the invention of semiconductor temperature measuring devices. They accurately respond to changes in temperature, but until recently did not have linearity.

Samuel Langley Very hot and molten metals dissipate heat and visible light. Nobili was able to detect this radiated energy by connecting thermocouples in series with the formation of a thermoelectric cell. The bolometer was discovered by the American Samuel Langley, the bolometer is the arrangement of two platinum bands, one of which turned black, in accordance with the structure of the Wheatstone bridge. Infrared radiation has led to a measurable change in resistance.

The ratio of the temperature scale Fahrenheit and Celsius

fahrenheit scale Celsius scale

Boiling point 212 ° 100 °

32 ° 0 ° freezing point

Temperature of absolute zero -459.67 ° -273.15 °

When converting from Fahrenheit to Celsius, subtract 32 from the original number and multiply by 5/9.

When converting from Celsius to Fahrenheit, the original number is multiplied by 9/5 and added 32.

Thermometers. German Gabriel Daniel Fahrenheit made a decisive contribution to the development of the design of thermometers. In 1709 he invented an alcohol thermometer, and in 1714 - a mercury thermometer. He gave them the same form that applies now. The success of his thermometers should be sought in the new method of purifying mercury introduced by him; In addition, before soldering, he boiled the liquid in the tube.

A copy is available to readers who want to deepen their knowledge in units of measurement. The part of physics that studies thermal phenomena, i.e. phenomena in which temperature and heat are critical. Temperature A physical size that expresses the thermal state of a system and describes its ability to exchange heat with the environment or other bodies. When two systems are placed in thermal contact, heat flows from the system to a higher temperature than the temperature below until reaching thermal equilibrium, where the two systems are at the same temperature. The concept of temperature is related to the idea of ​​providing a relative assessment of how the bodies are cold or hot to the touch. Therefore, the terms temperature and heat are correlated, but refer to different concepts: temperature is a property of the body, Heat is a form of energy that flows from one body to another to fill the temperature difference. Indirect methods based on the effects of heating or cooling are commonly used to obtain temperature measurements, the most commonly used method is dilatation measurement. A mercury thermometer measures the volume change of mercury placed in a glass capillary when it is brought into contact with a body of unknown temperature. The elongation of a mercury column is proportional to the body temperature. If the heat drops to an ideal gas contained in a vessel with a fixed volume, the temperature rise can be calculated by measuring the pressure change in the vessel. Temperature Scales. One of the first temperature scales was studied by the German physicist Gabriel Daniel Fahrenheit. However, in the scientific field absolute scale or Kelvin is invented by the British mathematician and physicist William Thomson Kelvin. The corresponding Rank rank is used mainly in landscapes. Page 1 of 4. Physics - Basic facts about temperature and its properties.

Rene Antoine de Reaumur did not approve of mercury use in thermometers due to the low coefficient of expansion of mercury. In 1730, he proposed to use alcohol in thermometers, as well. In 1731 he invented a water-alcohol thermometer. And since Reomur found that the alcohol used by him, mixed in a ratio of 5: 1 with water, expands in a ratio of 1000: 1080 as the temperature changes from freezing to boiling point of water, he suggested a scale from 0 to 80 °.

Calorimeter: laboratory experience

Physics. Measure the water equivalent of the calorimeter and measure the specific heat of the substance. If it had remained with Anders Tselis’s original idea about the České science, the current outdoor temperature would have been a hundred degrees. And the water below zero will not be cold, but will cook.

In the middle of the century, when it came from one hundred to zero, the temperature of a person was somehow on this Friday - and this was not without jumps. The first thermoscopes appeared at the end of the century, and a number of sciences joined their design. The most famous of these is the astronomer Galileo Galilei, whose version refers to the period of the temperature probe. It was a simple instrument: a glass tube closed on one side of the bay.

Scientists. Anders Celsius. Anders Celsius was born on November 27, 1701 in Sweden. His areas of interest: astronomy, general physics, geophysics.

He taught astronomy at Uppsala University, founded an astronomical observatory there.

Celsius first measured the brightness of stars, established the relationship between the northern lights and vibrations in the Earth’s magnetic field.

He took part in the Lapland expedition of 1736-1737 to measure the meridian. Upon returning from the polar regions, Celsius began active work on the organization and construction of the astronomical observatory in Uppsala and in 1740 became its director. Anders Celsius died March 25, 1744.

The mineral named Celsins is named after it - a kind of barium feldspar.

Gabriel Fahrenheit. Daniel Gabriel Fahrenheit (1686–1736) - German physicist. Born May 24, 1686 in Danzig (now Gdansk, Poland). He studied physics in Germany, Holland and England. Almost all his life he lived in Holland, where he was engaged in the manufacture of accurate meteorological instruments. In 1709 he made an alcohol, in 1714 - a mercury thermometer, using a new method of purifying mercury. For a mercury thermometer, Fahrenheit built a scale with three reference points: 0 ° corresponded to the water – ice – ammonia mixture temperature, 96 ° to the body temperature of a healthy person, and 32 ° for the ice melting point was taken as the reference temperature. The boiling point of pure water on the Fahrenheit scale was 212 °. The Fahrenheit scale is used in many English-speaking countries, although it gradually gives way to the Celsius scale. In addition to the manufacture of thermometers, Fahrenheit was engaged in the improvement of barometers and hygrometers. He also investigated the dependence of the change in the boiling point of a liquid on the atmospheric pressure and the salt content in it, discovered the phenomenon of supercooling of water, and compiled the tables of specific gravities of bodies. Fahrenheit died in the Hague on September 16, 1736.

Rene Reaumur. Rene Antoine de Reaumur (Rene Antoin de Reaumur) was born on February 28, 1683 in La Rochelle, a French naturalist, foreign honorary member of the St. Petersburg Academy of Sciences (1737). Works on regeneration, physiology, biology of colonies of insects. He proposed a temperature scale, named after him. He improved some methods of steel preparation; one of the first attempts were made to scientifically substantiate some of the casting processes, he wrote the work The Art of Transforming Iron into Steel. He came to a valuable conclusion, iron, steel, cast iron, differ in the amount of some impurity and by adding this admixture to iron, by cementation or fusing with iron Reomur received steel. In 1814, K. Careten proved that carbon is an impurity.

Reaumur gave a method of making frosted glass.

Today, memory connects his name only with the invention of a long-used temperature scale. In fact, Rene Antoine Ferschant de Reaumure, who lived in 1683-1757, mainly in Paris, belonged to those scientists whose universality in our time - the time of narrow specialization - is difficult to imagine. Reaumur was simultaneously a technician, physicist and naturalist. He gained great fame outside France as an entomologist. In the last years of his life, Reaumur came to the idea that the search for the mysterious transforming power should be conducted in those places where its manifestation is most obvious - when transforming food in the body, i.e. with her assimilation.

William Rankin. William John Macquarne Rankin (William John M. Rankine) (1820-72), Scottish engineer and physicist, one of the creators of technical thermodynamics. He proposed a theoretical steam engine cycle (Rankin cycle), a temperature scale (Rankin scale), the zero of which coincides with zero thermodynamic temperature, and in size 1 degree R. (° R) is 5/9 K (the scale is not widespread).

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