Multiple units- units that are an integer number of times greater than the basic unit of measurement of some physical quantity. International system Units (SI) recommends the following decimal prefixes for denoting multiples of units:

Applying decimal prefixes to binary units

Main article: Binary Prefixes

In programming and the computer-related industry, the same prefixes kilo-, mega-, giga-, tera-, etc., when applied to quantities that are multiples of powers of two (e.g., byte), may mean the multiplicity is not 1000, but 1024=2 10 . Which system is used should be clear from the context (for example, for the amount of RAM, the multiplicity of 1024 is used, and for the amount of disk memory, the multiplicity of 1000 is introduced by hard disk manufacturers).

To avoid confusion in April 1999 International electrotechnical commission introduced a new standard for naming binary numbers (see Binary Prefixes).

Prefixes for submultiple units

submultiple units, make up a certain proportion (part) of the established unit of measurement of a certain quantity. The International System of Units (SI) recommends the following prefixes for submultiple units:

Origin of prefixes

Most prefixes are derived from Greek words. Deca comes from the word Deca or deca(δέκα) - "ten", hecto - from hekaton(ἑκατόν) - "hundred", kilo - from chiloi(χίλιοι) - "thousand", mega - from megas(μέγας), i.e. "big", giga is gigantos(γίγας) - "giant", and tera - from teratos(τέρας), meaning "monstrous". Peta (πέντε) and exa (ἕξ) correspond to five and six thousand digits and are translated as "five" and "six" respectively. Dolny micro (from micros, μικρός) and nano (from nanos, νᾶνος) are translated as "small" and "dwarf". From one word ὀκτώ ( okto), meaning "eight", the prefixes yotta (1000 8) and yokto (1/1000 8) are formed.

How "thousand" is translated and the prefix milli, which goes back to lat. mille. Latin roots also have the prefix centi - from percent("hundred") and deci - from decimus("tenth"), zetta - from September("seven"). Zepto ("seven") comes from lat. words September or from fr. sept.

The prefix atto is formed from dates atten("eighteen"). Femto goes back to dates And Norwegian femten or to other-nor. fimmtan and means fifteen.

The prefix pico comes either from fr. pico("beak" or "small amount"), or from ital. piccolo i.e. "small".

Rules for using prefixes

Prefixes should be written together with the name of the unit or, accordingly, with its designation.

The use of two or more prefixes in a row (eg micromillifarad) is not permitted.

The designations of multiples and submultiples of the original unit raised to a power are formed by adding the corresponding exponent to the designation of a multiple or submultiple of the original unit, and the exponent means raising to the power of a multiple or submultiple unit (together with the prefix). Example: 1 km² = (10³ m)² = 10 6 m² (not 10³ m²). The names of such units are formed by adding a prefix to the name of the original unit: square kilometer (not kilo-square meter).

If the unit is a product or ratio of units, the prefix, or its designation, is usually attached to the name or designation of the first unit: kPa s / m (kilopascal second per meter). Attaching a prefix to the second factor of the product or to the denominator is allowed only in justified cases.

Applicability of prefixes

Due to the fact that the name of the unit of mass in SI- kilogram - contains the prefix "kilo", for the formation of multiple and submultiple units of mass, a submultiple unit of mass is used - grams (0.001 kg).

Prefixes are used to a limited extent with units of time: multiple prefixes are generally not combined with them - no one uses "kilosecond", although this is not formally prohibited, however, there is an exception to this rule: in cosmology unit is used gigayears» (billion years); dolly prefixes are attached only to second(millisecond, microsecond, etc.). In accordance with GOST 8.417-2002, the name and symbols of the following SI units are not allowed to be used with prefixes: minute, hour, day (time units), degree, minute, second(flat angle units), astronomical unit, diopter And atomic mass unit.

WITH meters of multiple prefixes, only kilo- is used in practice: instead of megameters (Mm), gigameters (Gm), etc., they write “thousands of kilometers”, “millions of kilometers”, etc .; instead of square megameters (Mm²), they write "millions of square kilometers."

Capacity capacitors traditionally measured in microfarads and picofarads, but not millifarads or nanofarads [ source unspecified 221 days ] (they write 60,000 pF, not 60 nF; 2000 uF, not 2 mF). However, in radio engineering, the use of a nanofarad unit is allowed.

Prefixes corresponding to exponents that are not divisible by 3 (hecto-, deca-, deci-, centi-) are not recommended. Widely used only centimeter(which is the basic unit in the system GHS) And decibel, to a lesser extent - decimeter and hectopascal (in meteorological reports), and hectare. In some countries the volume guilt measured in decalitres.

(SI), however, their use is not limited to the SI, and many of them date back to the time of the introduction of the metric system (1790s).

Requirements for units of quantities used in the Russian Federation are established federal law dated June 26, 2008 N 102-FZ "On ensuring the uniformity of measurements" . In particular, the law determines that the names of units of quantities allowed for use in the Russian Federation, their designations, spelling rules, as well as the rules for their application are established by the Government of the Russian Federation. In development of this norm, on October 31, 2009, the Government of the Russian Federation adopted the “Regulation on units of quantities allowed for use in Russian Federation”, in Appendix No. 5 to which decimal factors, prefixes and designations of prefixes for the formation of multiple and submultiple units of quantities are given. The same appendix contains rules regarding prefixes and their designations. In addition, the use of SI in Russia is regulated by the GOST 8.417-2002 standard.

With the exception of specially stipulated cases, the "Regulation on Units of Quantities Allowed for Use in the Russian Federation" allows the use of both Russian and international designations of units, but prohibits, however, their simultaneous use.

Prefixes for multiple units

Multiple units- units that are an integer number of times (10 to some extent) higher than the basic unit of measurement of some physical quantity. The International System of Units (SI) recommends the following decimal prefixes for denoting multiple units:

Application of decimal prefixes to units of quantity of information

The Regulation on Units of Values ​​Allowed for Use in the Russian Federation establishes that the name and designation of the unit of quantity of information “byte” (1 byte = 8 bits) are used with binary prefixes “Kilo”, “Mega”, “Giga”, which correspond to multipliers 2 10 , 2 20 and 2 30 (1 KB = 1024 bytes, 1 MB = 1024 KB, 1 GB = 1024 MB).

The same Regulations allow the use of the international designation of the unit of information with the prefixes "K" "M" "G" (KB, MB, GB, Kbyte, Mbyte, Gbyte).

In programming and the computer-related industry, the same prefixes "kilo", "mega", "giga", "tera", etc., when applied to values ​​that are multiples of powers of two (e.g., bytes), can mean both the multiplicity of 1000 and 1024=2 10 . Which system is used is sometimes clear from the context (for example, for the amount of RAM, the multiplicity of 1024 is used, and for the total amount of disk memory of hard drives, the multiplicity of 1000 is used).

To avoid confusion, in April 1999 the International Electrotechnical Commission introduced a new standard for naming binary numbers (see Binary prefixes).

Prefixes for submultiple units

submultiple units constitute a certain proportion (part) of the established unit of measurement of a certain quantity. The International System of Units (SI) recommends the following prefixes for submultiple units:

Origin of prefixes

Prefixes were introduced into the SI gradually. In 1960, the XI General Conference on Weights and Measures (CGPM) adopted a number of names of prefixes and corresponding symbols for factors ranging from 10 −12 to 10 12 . The prefixes for 10 −15 and 10 −18 were added by the XII CGPM in 1964, and for 10 15 and 10 18 by the XV CGPM in 1975. The last addition to the list of prefixes took place at the XIX CGPM in 1991, when they were adopted prefixes for factors 10 −24 , 10 −21 , 10 21 and 10 24 .

Most prefixes are derived from words ancient Greek. Deca - from other Greek. δέκα "ten", hecto- from other Greek. ἑκατόν "hundred", kilo - from other Greek. χίλιοι "thousand", mega- from other Greek. μέγας , that is, “big”, giga- is other Greek. γίγας - "giant", and tera - from other Greek. τέρας which means "monster". Peta- (other Greek. πέντε ) and exa- (other Greek. ἕξ ) correspond to five and six thousand digits and are translated, respectively, as “five” and “six”. Dolny micro- (from other Greek. μικρός ) and nano- (from other Greek. νᾶνος ) are translated as "small" and "dwarf". From one word, other Greek. ὀκτώ (okto), meaning "eight", the prefixes iotta (1000 8) and iokto (1/1000 8) are formed.

As "thousand" the prefix milli, which goes back to lat. mille. Latin roots also have the prefix centi - from percent("hundred") and deci - from decimus("tenth"), zetta - from September("seven"). Zepto ("seven") comes from lat. septem or from fr. sept.

The prefix atto is derived from dates. atten ("eighteen"). Femto goes back to dat. and Norwegian femten or other scand. fimmtān and means "fifteen".

The name of the prefix "pico" comes from the Italian. piccolo - small

Length and Distance Converter Mass Converter Bulk Solids and Foods Volume Converter Area Converter Volume and Units Converter recipes Temperature Converter Pressure, Stress, Young's Modulus Converter Energy and Work Converter Power Converter Force Converter Time Converter Linear Velocity Converter Flat Angle Thermal Efficiency and Fuel Economy Converter Numerical Number Converter Converter of Information Quantity Units Currency Rates Dimensions women's clothing and Shoe Sizes for Men's Clothing and Shoes Angular Velocity and Speed ​​Converter Acceleration Converter Angular Acceleration Converter Density Converter Specific Volume Converter Moment of Inertia Converter Moment of Force Converter Torque Converter Converter specific heat combustion (by mass) Energy density and specific heat of combustion (by volume) converter Temperature difference converter Thermal expansion coefficient converter Thermal resistance converter Thermal conductivity converter Specific heat capacity converter Energy exposure and thermal radiation power converter Density converter heat flow Heat Transfer Coefficient Converter Volume Flow Converter Mass Flow Converter Molar Flow Converter Mass Flux Density Converter Molar Concentration Converter Mass Solution Mass Concentration Converter Dynamic (Absolute) Viscosity Converter Kinematic Viscosity Converter Surface Tension Converter Vapor Permeability Converter Vapor Permeability and Vapor Transfer Velocity Converter Sound Level Converter Microphone Sensitivity Converter Sound pressure level (SPL) converter Sound pressure level converter with selectable reference pressure Brightness converter Luminous intensity converter Illuminance converter Computer graphics resolution converter Frequency and wavelength converter Diopter power and focal length Diopter power and lens magnification (×) Electric Charge Converter Linear Charge Density Converter Surface Charge Density Converter Bulk Charge Density Converter Converter electric current Linear Current Density Converter Surface Current Density Converter Voltage Converter electric field Electrostatic Potential and Voltage Converter Converter electrical resistance Electrical Resistivity Converter Electrical Conductivity Converter Electrical Conductivity Converter Capacitance Inductance Converter US Wire Gauge Converter Levels in dBm (dBm or dBm), dBV (dBV), Watts, etc. Units Magnetomotive Force Converter Strength Converter magnetic field Converter magnetic flux Magnetic Induction Converter Radiation. Ionizing Radiation Absorbed Dose Rate Converter Radioactivity. Radioactive Decay Converter Radiation. Exposure Dose Converter Radiation. Absorbed Dose Converter Decimal Prefix Converter Data Transfer Typographic and Imaging Unit Converter Timber Volume Unit Converter molar mass Periodic system chemical elements D. I. Mendeleev

1 mega [M] = 0.001 giga [G]

Initial value

Converted value

no prefix yotta zetta exa peta tera giga mega kilo hecto deca deci centi milli micro nano pico femto atto zepto yocto

Metric system and International System of Units (SI)

Introduction

In this article, we will talk about the metric system and its history. We will see how and why it began and how it gradually developed into what we have today. We will also look at the SI system, which was developed from the metric system of measures.

For our ancestors, who lived in a world full of dangers, the ability to measure various quantities in natural environment habitation made it possible to get closer to understanding the essence of natural phenomena, knowledge of their environment and getting the opportunity to somehow influence what surrounded them. That is why people tried to invent and improve various measurement systems. At the dawn of human development, having a measurement system was no less important than it is now. It was necessary to perform various measurements during the construction of housing, sewing clothes different sizes, cooking and, of course, trade and exchange could not do without measurement! Many believe that the creation and adoption of the International System of Units SI is the most serious achievement not only of science and technology, but also of the development of mankind in general.

Early measurement systems

In early measurement and number systems, people used traditional objects to measure and compare. For example, it is believed that the decimal system appeared due to the fact that we have ten fingers and toes. Our hands are always with us - that's why since ancient times people used (and still use) fingers for counting. Yet we have not always used base 10 for counting, and the metric system is a relatively new invention. Each region has its own systems of units, and although these systems have much in common, most of the systems are still so different that the conversion of units from one system to another has always been a problem. This problem became more and more serious as trade between different peoples developed.

The accuracy of the first systems of measures and weights directly depended on the size of the objects that surrounded the people who developed these systems. It is clear that the measurements were inaccurate, since the "measuring devices" did not have exact dimensions. For example, body parts were commonly used as a measure of length; mass and volume were measured using the volume and mass of seeds and other small objects, the dimensions of which were more or less the same. We will discuss these units in more detail below.

Measures of length

IN Ancient Egypt length was measured at first elbows, and later royal elbows. The length of the elbow was defined as the segment from the bend of the elbow to the end of the extended middle finger. Thus, the royal cubit was defined as the cubit of the reigning pharaoh. A model cubit was created and made available to the general public so that everyone could make their own measures of length. This, of course, was an arbitrary unit that changed when a new royal took the throne. Ancient Babylon used a similar system, but with slight differences.

The cubit was divided into smaller units: palm, hand, zerets(foot), and you(finger), which were represented respectively by the width of the palm, hand (with thumb), foot and finger. At the same time, they decided to agree on how many fingers in the palm (4), in the hand (5) and elbow (28 in Egypt and 30 in Babylon). It was more convenient and more accurate than measuring ratios every time.

Measures of mass and weight

Measures of weight were also based on the parameters of various objects. Seeds, grains, beans and similar items acted as measures of weight. The classic example of a unit of mass still in use today is carat. Now carats measure the mass of precious stones and pearls, and once the weight of carob seeds, otherwise called carob, was determined as a carat. The tree is cultivated in the Mediterranean, and its seeds are distinguished by the constancy of mass, so it was convenient to use them as a measure of weight and mass. IN different places different seeds were used as small units of weight, and larger units were usually multiples of smaller units. Archaeologists often find similar large weights, usually made of stone. They consisted of 60, 100 and a different number of small units. Since there was no single standard for the number of small items, as well as for their weight, this led to conflicts when sellers and buyers who lived in different places met.

Measures of volume

Initially, volume was also measured using small objects. For example, the volume of a pot or jug ​​was determined by filling it to the top with small objects of a relatively standard volume - like seeds. However, the lack of standardization led to the same problems in measuring volume as in measuring mass.

Evolution of different systems of measures

The ancient Greek system of measures was based on the ancient Egyptian and Babylonian, and the Romans created their own system based on the ancient Greek. Then by fire and sword and, of course, as a result of trade, these systems spread throughout Europe. It should be noted that here we are talking only about the most common systems. But there were many other systems of measures and weights, because exchange and trade were necessary for absolutely everyone. If there was no writing in the given area or it was not customary to record the results of the exchange, then we can only guess how these people measured volume and weight.

There are many regional variants of systems of measures and weights. This is due to their independent development and the influence of other systems on them as a result of trade and conquest. Various systems were not only in different countries, but often within the same country, where in each trading city they were their own, because the local rulers did not want unification in order to maintain their power. With the development of travel, trade, industry and science, many countries sought to unify systems of measures and weights, at least in the territories of their countries.

Already in the 13th century, and possibly earlier, scientists and philosophers discussed the creation unified system measurements. However, only after French Revolution and subsequent colonization of various regions of the world by France and others European countries, which already had their own systems of measures and weights, a new system was developed, adopted in most countries of the world. This new system was decimal metric system. It was based on the base 10, that is, for any physical quantity there was one basic unit in it, and all other units could be formed in a standard way using decimal prefixes. Each such fractional or multiple unit could be divided into ten smaller units, and these smaller units, in turn, could be divided into 10 even smaller units, and so on.

As we know, most of the early measurement systems were not based on base 10. The convenience of the system with base 10 is that the number system we are used to has the same base, which allows you to quickly and conveniently use simple and familiar rules to convert from smaller units to large and vice versa. Many scientists believe that the choice of ten as the base of the number system is arbitrary and is associated only with the fact that we have ten fingers, and if we had a different number of fingers, then we would probably use a different number system.

Metric system

In the early days of the metric system, human-made prototypes were used as measures of length and weight, as in previous systems. The metric system has evolved from a system based on real standards and dependence on their accuracy to a system based on natural phenomena and fundamental physical constants. For example, the unit of time, the second, was originally defined as part of the tropical year 1900. The disadvantage of such a definition was the impossibility of experimental verification of this constant in subsequent years. Therefore, the second was redefined as a certain number of periods of radiation corresponding to the transition between two hyperfine levels of the ground state of a radioactive caesium-133 atom at rest at 0 K. The unit of distance, the meter, was associated with the wavelength of the emission spectrum of the isotope krypton-86, but later The meter was redefined as the distance traveled by light in a vacuum in a time interval of 1/299,792,458 of a second.

Based on the metric system, the International System of Units (SI) was created. It should be noted that traditionally the metric system includes units of mass, length and time, but in the SI system the number of base units has been expanded to seven. We will discuss them below.

International System of Units (SI)

The International System of Units (SI) has seven basic units for measuring basic quantities (mass, time, length, luminous intensity, amount of matter, electric current, thermodynamic temperature). This kilogram(kg) for mass measurement, second(c) to measure time, meter(m) for distance measurement, candela(cd) to measure the intensity of light, mole(abbreviation mol) to measure the amount of a substance, ampere(A) to measure the strength of the electric current, and kelvin(K) for temperature measurement.

At present, only the kilogram still has a man-made standard, while the rest of the units are based on universal physical constants or on natural phenomena. This is convenient because the physical constants or natural phenomena on which units of measurement are based can be easily checked at any time; moreover, there is no danger of loss or damage to standards. There is also no need to create copies of standards to ensure their availability in different points planets. This eliminates errors associated with the accuracy of making copies of physical objects, and thus provides greater accuracy.

Decimal Prefixes

To form multiple and submultiple units that differ from the base units of the SI system by a certain integer number of times, which is a power of ten, it uses prefixes attached to the name of the base unit. The following is a list of all prefixes currently in use and the decimal factors they stand for:

For example, 5 gigameters equals 5,000,000,000 meters, while 3 microcandela equals 0.000003 candela. It is interesting to note that, despite the presence of a prefix in the unit kilogram, it is the base SI unit. Therefore, the above prefixes are used with the gram as if it were the base unit.

At the time of this writing, only three countries remain that have not adopted the SI system: the United States, Liberia, and Myanmar. In Canada and the United Kingdom, traditional units are still widely used, despite the fact that the SI system in these countries is the official system of units. It is enough to go to the store and see the price tags for a pound of goods (it’s cheaper, after all!), Or try to buy building materials measured in meters and kilograms. Will not work! Not to mention the packaging of goods, where everything is signed in grams, kilograms and liters, but not in whole, but translated from pounds, ounces, pints and quarts. Milk space in refrigerators is also calculated per half gallon or gallon, not per liter milk carton.

Do you find it difficult to translate units of measurement from one language to another? Colleagues are ready to help you. Post a question to TCTerms and within a few minutes you will receive an answer.

Calculations for converting units in the converter " Decimal prefix converter' are performed using the functions of unitconversion.org .

Length and Distance Converter Mass Converter Bulk Food and Food Volume Converter Area Converter Volume and Recipe Units Converter Temperature Converter Pressure, Stress, Young's Modulus Converter Energy and Work Converter Power Converter Force Converter Time Converter Linear Velocity Converter Flat Angle Converter thermal efficiency and fuel efficiency Converter of numbers in different number systems Converter of units of measurement of quantity of information Currency rates Dimensions of women's clothing and shoes Dimensions of men's clothing and shoes Angular velocity and rotation frequency converter Acceleration converter Angular acceleration converter Density converter Specific volume converter Moment of inertia converter Moment of force converter Torque converter Specific heat of combustion (by mass) Converter Energy density and specific heat of combustion of fuel (by volume) Temperature difference converter Thermal expansion coefficient converter Thermal resistance converter Thermal conductivity converter Specific heat capacity converter Energy exposure and thermal radiation power converter Heat flux density converter Heat Transfer Coefficient Converter Volume Flow Converter Mass Flow Converter Molar Flow Converter Mass Flux Density Converter Molar Concentration Converter Mass Solution Mass Concentration Converter Dynamic (Absolute) Viscosity Converter Kinematic Viscosity Converter Surface Tension Converter Vapor Permeability Converter Vapor Permeability and Vapor Transfer Velocity Converter Sound Level Converter Microphone Sensitivity Converter Sound pressure level (SPL) converter Sound pressure level converter with selectable reference pressure Brightness converter Luminous intensity converter Illuminance converter Computer graphics resolution converter Frequency and wavelength converter Diopter power and focal length Diopter power and lens magnification (×) Electric Charge Converter Linear Charge Density Converter Surface Charge Density Converter Volumetric Charge Density Converter Electric Current Converter Linear Current Density Converter Surface Current Density Converter Electric Field Strength Converter Electrostatic Potential and Voltage Converter Electrical Resistance Converter Electrical Resistivity Converter Electrical Conductivity Converter Electrical Conductivity Converter Electrical capacitance Inductance converter American wire gauge converter Levels in dBm (dBm or dBm), dBV (dBV), watts, etc. units Magnetomotive force converter Magnetic field strength converter Magnetic flux converter Magnetic induction converter Radiation. Ionizing Radiation Absorbed Dose Rate Converter Radioactivity. Radioactive Decay Converter Radiation. Exposure Dose Converter Radiation. Absorbed Dose Converter Decimal Prefix Converter Data Transfer Typographic and Image Processing Unit Converter Timber Volume Unit Converter Calculation of Molar Mass Periodic Table of Chemical Elements by D. I. Mendeleev

1 milli [m] = 1000 micro [µ]

Initial value

Converted value

no prefix yotta zetta exa peta tera giga mega kilo hecto deca deci centi milli micro nano pico femto atto zepto yocto

Optical power in diopters and lens magnification

Metric system and International System of Units (SI)

Introduction

In this article, we will talk about the metric system and its history. We will see how and why it began and how it gradually developed into what we have today. We will also look at the SI system, which was developed from the metric system of measures.

For our ancestors, who lived in a world full of dangers, the ability to measure various quantities in their natural habitat made it possible to get closer to understanding the essence of natural phenomena, understanding their environment and gaining the opportunity to somehow influence what surrounded them. That is why people tried to invent and improve various measurement systems. At the dawn of human development, having a measurement system was no less important than it is now. It was necessary to perform various measurements during the construction of housing, sewing clothes of different sizes, cooking, and, of course, trade and exchange could not do without measurement! Many believe that the creation and adoption of the International System of Units SI is the most serious achievement not only of science and technology, but also of the development of mankind in general.

Early measurement systems

In early measurement and number systems, people used traditional objects to measure and compare. For example, it is believed that the decimal system appeared due to the fact that we have ten fingers and toes. Our hands are always with us - that's why since ancient times people used (and still use) fingers for counting. Yet we have not always used base 10 for counting, and the metric system is a relatively new invention. Each region has its own systems of units, and although these systems have much in common, most of the systems are still so different that the conversion of units from one system to another has always been a problem. This problem became more and more serious as trade between different peoples developed.

The accuracy of the first systems of measures and weights directly depended on the size of the objects that surrounded the people who developed these systems. It is clear that the measurements were inaccurate, since the "measuring devices" did not have exact dimensions. For example, body parts were commonly used as a measure of length; mass and volume were measured using the volume and mass of seeds and other small objects, the dimensions of which were more or less the same. We will discuss these units in more detail below.

Measures of length

In ancient Egypt, length was first measured simply elbows, and later royal elbows. The length of the elbow was defined as the segment from the bend of the elbow to the end of the extended middle finger. Thus, the royal cubit was defined as the cubit of the reigning pharaoh. A model cubit was created and made available to the general public so that everyone could make their own measures of length. This, of course, was an arbitrary unit that changed when a new royal took the throne. Ancient Babylon used a similar system, but with slight differences.

The cubit was divided into smaller units: palm, hand, zerets(foot), and you(finger), which were represented respectively by the width of the palm, hand (with thumb), foot and finger. At the same time, they decided to agree on how many fingers in the palm (4), in the hand (5) and elbow (28 in Egypt and 30 in Babylon). It was more convenient and more accurate than measuring ratios every time.

Measures of mass and weight

Measures of weight were also based on the parameters of various objects. Seeds, grains, beans and similar items acted as measures of weight. The classic example of a unit of mass still in use today is carat. Now carats measure the mass of precious stones and pearls, and once the weight of carob seeds, otherwise called carob, was determined as a carat. The tree is cultivated in the Mediterranean, and its seeds are distinguished by the constancy of mass, so it was convenient to use them as a measure of weight and mass. In different places, different seeds were used as small units of weight, and larger units were usually multiples of smaller units. Archaeologists often find similar large weights, usually made of stone. They consisted of 60, 100 and a different number of small units. Since there was no single standard for the number of small items, as well as for their weight, this led to conflicts when sellers and buyers who lived in different places met.

Measures of volume

Initially, volume was also measured using small objects. For example, the volume of a pot or jug ​​was determined by filling it to the top with small objects of a relatively standard volume - like seeds. However, the lack of standardization led to the same problems in measuring volume as in measuring mass.

Evolution of different systems of measures

The ancient Greek system of measures was based on the ancient Egyptian and Babylonian, and the Romans created their own system based on the ancient Greek. Then by fire and sword and, of course, as a result of trade, these systems spread throughout Europe. It should be noted that here we are talking only about the most common systems. But there were many other systems of measures and weights, because exchange and trade were necessary for absolutely everyone. If there was no writing in the given area or it was not customary to record the results of the exchange, then we can only guess how these people measured volume and weight.

There are many regional variants of systems of measures and weights. This is due to their independent development and the influence of other systems on them as a result of trade and conquest. Different systems were not only in different countries, but often within the same country, where each trading city had its own, because the local rulers did not want unification in order to maintain their power. With the development of travel, trade, industry and science, many countries sought to unify systems of measures and weights, at least in the territories of their countries.

Already in the 13th century, and possibly earlier, scientists and philosophers discussed the creation of a unified system of measurements. However, only after the French Revolution and the subsequent colonization of various regions of the world by France and other European countries, which already had their own systems of measures and weights, a new system was developed, adopted in most countries of the world. This new system was decimal metric system. It was based on the base 10, that is, for any physical quantity there was one basic unit in it, and all other units could be formed in a standard way using decimal prefixes. Each such fractional or multiple unit could be divided into ten smaller units, and these smaller units, in turn, could be divided into 10 even smaller units, and so on.

As we know, most of the early measurement systems were not based on base 10. The convenience of the system with base 10 is that the number system we are used to has the same base, which allows you to quickly and conveniently use simple and familiar rules to convert from smaller units to large and vice versa. Many scientists believe that the choice of ten as the base of the number system is arbitrary and is associated only with the fact that we have ten fingers, and if we had a different number of fingers, then we would probably use a different number system.

Metric system

In the early days of the metric system, human-made prototypes were used as measures of length and weight, as in previous systems. The metric system has evolved from a system based on real standards and dependence on their accuracy to a system based on natural phenomena and fundamental physical constants. For example, the unit of time, the second, was originally defined as part of the tropical year 1900. The disadvantage of such a definition was the impossibility of experimental verification of this constant in subsequent years. Therefore, the second was redefined as a certain number of periods of radiation corresponding to the transition between two hyperfine levels of the ground state of a radioactive caesium-133 atom at rest at 0 K. The unit of distance, the meter, was associated with the wavelength of the emission spectrum of the isotope krypton-86, but later The meter was redefined as the distance traveled by light in a vacuum in a time interval of 1/299,792,458 of a second.

Based on the metric system, the International System of Units (SI) was created. It should be noted that traditionally the metric system includes units of mass, length and time, but in the SI system the number of base units has been expanded to seven. We will discuss them below.

International System of Units (SI)

The International System of Units (SI) has seven basic units for measuring basic quantities (mass, time, length, luminous intensity, amount of matter, electric current, thermodynamic temperature). This kilogram(kg) for mass measurement, second(c) to measure time, meter(m) for distance measurement, candela(cd) to measure the intensity of light, mole(abbreviation mol) to measure the amount of a substance, ampere(A) to measure the strength of the electric current, and kelvin(K) for temperature measurement.

At present, only the kilogram still has a man-made standard, while the rest of the units are based on universal physical constants or on natural phenomena. This is convenient because the physical constants or natural phenomena on which units of measurement are based can be easily checked at any time; moreover, there is no danger of loss or damage to standards. There is also no need to create copies of standards to ensure their availability in different parts of the world. This eliminates errors associated with the accuracy of making copies of physical objects, and thus provides greater accuracy.

Decimal Prefixes

To form multiple and submultiple units that differ from the base units of the SI system by a certain integer number of times, which is a power of ten, it uses prefixes attached to the name of the base unit. The following is a list of all prefixes currently in use and the decimal factors they stand for:

For example, 5 gigameters equals 5,000,000,000 meters, while 3 microcandela equals 0.000003 candela. It is interesting to note that, despite the presence of a prefix in the unit kilogram, it is the base SI unit. Therefore, the above prefixes are used with the gram as if it were the base unit.

At the time of this writing, only three countries remain that have not adopted the SI system: the United States, Liberia, and Myanmar. In Canada and the United Kingdom, traditional units are still widely used, despite the fact that the SI system in these countries is the official system of units. It is enough to go to the store and see the price tags for a pound of goods (it’s cheaper, after all!), Or try to buy building materials measured in meters and kilograms. Will not work! Not to mention the packaging of goods, where everything is signed in grams, kilograms and liters, but not in whole, but translated from pounds, ounces, pints and quarts. Milk space in refrigerators is also calculated per half gallon or gallon, not per liter milk carton.

Do you find it difficult to translate units of measurement from one language to another? Colleagues are ready to help you. Post a question to TCTerms and within a few minutes you will receive an answer.

Calculations for converting units in the converter " Decimal prefix converter' are performed using the functions of unitconversion.org .

Length and Distance Converter Mass Converter Bulk Food and Food Volume Converter Area Converter Volume and Recipe Units Converter Temperature Converter Pressure, Stress, Young's Modulus Converter Energy and Work Converter Power Converter Force Converter Time Converter Linear Velocity Converter Flat Angle Converter thermal efficiency and fuel efficiency Converter of numbers in different number systems Converter of units of measurement of quantity of information Currency rates Dimensions of women's clothing and shoes Dimensions of men's clothing and shoes Angular velocity and rotation frequency converter Acceleration converter Angular acceleration converter Density converter Specific volume converter Moment of inertia converter Moment of force converter Torque converter Specific heat of combustion (by mass) Converter Energy density and specific heat of combustion of fuel (by volume) Temperature difference converter Thermal expansion coefficient converter Thermal resistance converter Thermal conductivity converter Specific heat capacity converter Energy exposure and thermal radiation power converter Heat flux density converter Heat Transfer Coefficient Converter Volume Flow Converter Mass Flow Converter Molar Flow Converter Mass Flux Density Converter Molar Concentration Converter Mass Solution Mass Concentration Converter Dynamic (Absolute) Viscosity Converter Kinematic Viscosity Converter Surface Tension Converter Vapor Permeability Converter Vapor Permeability and Vapor Transfer Velocity Converter Sound Level Converter Microphone Sensitivity Converter Sound pressure level (SPL) converter Sound pressure level converter with selectable reference pressure Brightness converter Luminous intensity converter Illuminance converter Computer graphics resolution converter Frequency and wavelength converter Diopter power and focal length Diopter power and lens magnification (×) Electric Charge Converter Linear Charge Density Converter Surface Charge Density Converter Volumetric Charge Density Converter Electric Current Converter Linear Current Density Converter Surface Current Density Converter Electric Field Strength Converter Electrostatic Potential and Voltage Converter Electrical Resistance Converter Electrical Resistivity Converter Electrical Conductivity Converter Electrical Conductivity Converter Electrical capacitance Inductance converter American wire gauge converter Levels in dBm (dBm or dBm), dBV (dBV), watts, etc. units Magnetomotive force converter Magnetic field strength converter Magnetic flux converter Magnetic induction converter Radiation. Ionizing Radiation Absorbed Dose Rate Converter Radioactivity. Radioactive Decay Converter Radiation. Exposure Dose Converter Radiation. Absorbed Dose Converter Decimal Prefix Converter Data Transfer Typographic and Image Processing Unit Converter Timber Volume Unit Converter Calculation of Molar Mass Periodic Table of Chemical Elements by D. I. Mendeleev

1 micro [µ] = 1000 nano [n]

Initial value

Converted value

no prefix yotta zetta exa peta tera giga mega kilo hecto deca deci centi milli micro nano pico femto atto zepto yocto

Metric system and International System of Units (SI)

Introduction

In this article, we will talk about the metric system and its history. We will see how and why it began and how it gradually developed into what we have today. We will also look at the SI system, which was developed from the metric system of measures.

For our ancestors, who lived in a world full of dangers, the ability to measure various quantities in their natural habitat made it possible to get closer to understanding the essence of natural phenomena, understanding their environment and gaining the opportunity to somehow influence what surrounded them. That is why people tried to invent and improve various measurement systems. At the dawn of human development, having a measurement system was no less important than it is now. It was necessary to perform various measurements during the construction of housing, sewing clothes of different sizes, cooking, and, of course, trade and exchange could not do without measurement! Many believe that the creation and adoption of the International System of Units SI is the most serious achievement not only of science and technology, but also of the development of mankind in general.

Early measurement systems

In early measurement and number systems, people used traditional objects to measure and compare. For example, it is believed that the decimal system appeared due to the fact that we have ten fingers and toes. Our hands are always with us - that's why since ancient times people used (and still use) fingers for counting. Yet we have not always used base 10 for counting, and the metric system is a relatively new invention. Each region has its own systems of units, and although these systems have much in common, most of the systems are still so different that the conversion of units from one system to another has always been a problem. This problem became more and more serious as trade between different peoples developed.

The accuracy of the first systems of measures and weights directly depended on the size of the objects that surrounded the people who developed these systems. It is clear that the measurements were inaccurate, since the "measuring devices" did not have exact dimensions. For example, body parts were commonly used as a measure of length; mass and volume were measured using the volume and mass of seeds and other small objects, the dimensions of which were more or less the same. We will discuss these units in more detail below.

Measures of length

In ancient Egypt, length was first measured simply elbows, and later royal elbows. The length of the elbow was defined as the segment from the bend of the elbow to the end of the extended middle finger. Thus, the royal cubit was defined as the cubit of the reigning pharaoh. A model cubit was created and made available to the general public so that everyone could make their own measures of length. This, of course, was an arbitrary unit that changed when a new royal took the throne. Ancient Babylon used a similar system, but with slight differences.

The cubit was divided into smaller units: palm, hand, zerets(foot), and you(finger), which were represented respectively by the width of the palm, hand (with thumb), foot and finger. At the same time, they decided to agree on how many fingers in the palm (4), in the hand (5) and elbow (28 in Egypt and 30 in Babylon). It was more convenient and more accurate than measuring ratios every time.

Measures of mass and weight

Measures of weight were also based on the parameters of various objects. Seeds, grains, beans and similar items acted as measures of weight. The classic example of a unit of mass still in use today is carat. Now carats measure the mass of precious stones and pearls, and once the weight of carob seeds, otherwise called carob, was determined as a carat. The tree is cultivated in the Mediterranean, and its seeds are distinguished by the constancy of mass, so it was convenient to use them as a measure of weight and mass. In different places, different seeds were used as small units of weight, and larger units were usually multiples of smaller units. Archaeologists often find similar large weights, usually made of stone. They consisted of 60, 100 and a different number of small units. Since there was no single standard for the number of small items, as well as for their weight, this led to conflicts when sellers and buyers who lived in different places met.

Measures of volume

Initially, volume was also measured using small objects. For example, the volume of a pot or jug ​​was determined by filling it to the top with small objects of a relatively standard volume - like seeds. However, the lack of standardization led to the same problems in measuring volume as in measuring mass.

Evolution of different systems of measures

The ancient Greek system of measures was based on the ancient Egyptian and Babylonian, and the Romans created their own system based on the ancient Greek. Then by fire and sword and, of course, as a result of trade, these systems spread throughout Europe. It should be noted that here we are talking only about the most common systems. But there were many other systems of measures and weights, because exchange and trade were necessary for absolutely everyone. If there was no writing in the given area or it was not customary to record the results of the exchange, then we can only guess how these people measured volume and weight.

There are many regional variants of systems of measures and weights. This is due to their independent development and the influence of other systems on them as a result of trade and conquest. Different systems were not only in different countries, but often within the same country, where each trading city had its own, because the local rulers did not want unification in order to maintain their power. With the development of travel, trade, industry and science, many countries sought to unify systems of measures and weights, at least in the territories of their countries.

Already in the 13th century, and possibly earlier, scientists and philosophers discussed the creation of a unified system of measurements. However, only after the French Revolution and the subsequent colonization of various regions of the world by France and other European countries, which already had their own systems of measures and weights, a new system was developed, adopted in most countries of the world. This new system was decimal metric system. It was based on the base 10, that is, for any physical quantity there was one basic unit in it, and all other units could be formed in a standard way using decimal prefixes. Each such fractional or multiple unit could be divided into ten smaller units, and these smaller units, in turn, could be divided into 10 even smaller units, and so on.

As we know, most of the early measurement systems were not based on base 10. The convenience of the system with base 10 is that the number system we are used to has the same base, which allows you to quickly and conveniently use simple and familiar rules to convert from smaller units to large and vice versa. Many scientists believe that the choice of ten as the base of the number system is arbitrary and is associated only with the fact that we have ten fingers, and if we had a different number of fingers, then we would probably use a different number system.

Metric system

In the early days of the metric system, human-made prototypes were used as measures of length and weight, as in previous systems. The metric system has evolved from a system based on real standards and dependence on their accuracy to a system based on natural phenomena and fundamental physical constants. For example, the unit of time, the second, was originally defined as part of the tropical year 1900. The disadvantage of such a definition was the impossibility of experimental verification of this constant in subsequent years. Therefore, the second was redefined as a certain number of periods of radiation corresponding to the transition between two hyperfine levels of the ground state of a radioactive caesium-133 atom at rest at 0 K. The unit of distance, the meter, was associated with the wavelength of the emission spectrum of the isotope krypton-86, but later The meter was redefined as the distance traveled by light in a vacuum in a time interval of 1/299,792,458 of a second.

Based on the metric system, the International System of Units (SI) was created. It should be noted that traditionally the metric system includes units of mass, length and time, but in the SI system the number of base units has been expanded to seven. We will discuss them below.

International System of Units (SI)

The International System of Units (SI) has seven basic units for measuring basic quantities (mass, time, length, luminous intensity, amount of matter, electric current, thermodynamic temperature). This kilogram(kg) for mass measurement, second(c) to measure time, meter(m) for distance measurement, candela(cd) to measure the intensity of light, mole(abbreviation mol) to measure the amount of a substance, ampere(A) to measure the strength of the electric current, and kelvin(K) for temperature measurement.

At present, only the kilogram still has a man-made standard, while the rest of the units are based on universal physical constants or on natural phenomena. This is convenient because the physical constants or natural phenomena on which units of measurement are based can be easily checked at any time; moreover, there is no danger of loss or damage to standards. There is also no need to create copies of standards to ensure their availability in different parts of the world. This eliminates errors associated with the accuracy of making copies of physical objects, and thus provides greater accuracy.

Decimal Prefixes

To form multiple and submultiple units that differ from the base units of the SI system by a certain integer number of times, which is a power of ten, it uses prefixes attached to the name of the base unit. The following is a list of all prefixes currently in use and the decimal factors they stand for:

For example, 5 gigameters equals 5,000,000,000 meters, while 3 microcandela equals 0.000003 candela. It is interesting to note that, despite the presence of a prefix in the unit kilogram, it is the base SI unit. Therefore, the above prefixes are used with the gram as if it were the base unit.

At the time of this writing, only three countries remain that have not adopted the SI system: the United States, Liberia, and Myanmar. In Canada and the United Kingdom, traditional units are still widely used, despite the fact that the SI system in these countries is the official system of units. It is enough to go to the store and see the price tags for a pound of goods (it’s cheaper, after all!), Or try to buy building materials measured in meters and kilograms. Will not work! Not to mention the packaging of goods, where everything is signed in grams, kilograms and liters, but not in whole, but translated from pounds, ounces, pints and quarts. Milk space in refrigerators is also calculated per half gallon or gallon, not per liter milk carton.

Do you find it difficult to translate units of measurement from one language to another? Colleagues are ready to help you. Post a question to TCTerms and within a few minutes you will receive an answer.

Calculations for converting units in the converter " Decimal prefix converter' are performed using the functions of unitconversion.org .