I hope this will help the forum users to more competently and thoughtfully operate with consoles and physical quantities. Distinguish milli (m) from mega (M), correctly record the designations of electrical quantities, etc.

Main sources of information:

1. DSTU 3651.0-97 "Metrology. Units of physical quantities. Basic units of physical quantities of the International System of Units. Fundamentals, names and designations";
2. DSTU 3651.1-97 "Metrology. Units of physical quantities. Derivative units of physical quantities of the International System of Units and non-systemic units. Basic concepts, names and designations";
3. DSTU 3651.2-97 "Metrology. Units of physical quantities. Physical constants and characteristic numbers. Fundamentals, designations, names and values."

The main units of the International System of Units SI (SI) are:

meter (m) - the length of the path traveled by light in vacuum for a time interval of 1/299 792 458 s;

kilogram (kg) is a unit of mass equal to the mass of the international prototype of the kilogram;

second (s) is the time equal to 9,192,631,770 periods of radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium-133 atom;

ampere (A) is a force of unchanging current, which, when passing along two parallel conductors of infinite length and a negligibly small area of \u200b\u200bcircular cross-section, located in a vacuum at a distance of 1 m one from the other, would cause an interaction force equal to 2 · 10 -7 N;

kelvin (K) is a unit of thermodynamic temperature equal to 1 / 273.16 parts of the thermodynamic temperature of the triple point of water;

candela (cd) - luminous intensity in a given direction from a source emitting monochromatic radiation at a frequency of 540 · 1012 Hz, the luminous intensity of which in this direction is 1/683 W / sr;

mol (mol) is the amount of a system substance containing as many molecules (atoms, particles) as there are atoms in carbon-12 with a mass of 0.012 kg.

Derivatives of the International System of Units are:

radian (rad) is a flat angle unit, 1 rad \u003d 1 m / m \u003d 1;

steradian (cf) - unit of solid angle, 1 sr \u003d 1 m 2 / m 2 \u003d 1;

hertz (Hz) is a unit of frequency, 1 Hz \u003d 1 s -1;

newton (N) is the unit of force and weight, 1 N \u003d 1 kg · m / s 2;

pascal (Pa) - pressure unit, (mechanical) stress, 1 Pa \u003d 1 N / m 2;

joule (J) is a unit of energy, work, quantity of heat, 1 J \u003d 1 N · m;

watt (W) - unit of power, radiation flux, 1 W \u003d 1 J / s;

pendant (C) - unit of electric charge, amount of electricity, 1 C \u003d 1 A · s;

volt (V) is the unit of electric potential, (electrical) voltage, electromotive force, 1 V \u003d 1 W / A;

farad (F) - unit of electrical capacity, 1 F \u003d 1 C / V;

ohm (Ohm) - unit of electrical resistance, 1 Ohm \u003d 1 V / A;

siemens (Cm) - unit of electrical conductivity, 1 Cm \u003d 1 Ω -1;

weber (Wb) - unit of magnetic flux, 1 Wb \u003d 1 V · s;

tesla (T) - unit of magnetic induction, 1 T \u003d 1 Wb / m 2;

henry (H) is the inductance unit, 1 H \u003d 1 Wb / m;

degree Celsius (° C) - unit of temperature Celsius, 1 ° C \u003d 1 K;

lumen (lm) is a unit of luminous flux, 1 lm \u003d 1 cd · sr; ·

lux (lx) is a unit of illumination, 1 lx \u003d 1 lm / m 2;

becquerel (Bq) is a unit of activity (radionuclide), 1 Bq \u003d 1 s -1;

gray (Gy) - unit of the absorbed dose (ionizing radiation), specific transmitted energy, 1 Gy \u003d 1 J / kg;

sievert (Sv) is a unit of equivalent dose (ionizing radiation), 1 Sv \u003d 1 J / kg

Other units:

bit (b) - the smallest possible unit of information in computing. One bit of binary code (binary digit). It can take only two mutually exclusive values: yes / no, 1/0, on / off, and so on.

byte (B) is a unit of measurement for the amount of information, usually equal to eight bits (in this case, it can take 256 (2 8) different values).

• The designations of units derived from last names are written with a capital letter, including the SI prefixes, for example: ampere - A, megapascal - MPa, kilonewton - kN, gigahertz - GHz.
• The designations of units are printed in right type, the point as a reduction sign after the designation is not set.
• Designations are placed after the numerical values \u200b\u200bof the values \u200b\u200bseparated by a space., wrap to another line is not allowed. Exceptions are the notation in the form of a sign above the line, before them the space is not put. Examples: 10 m / s, 15 °.
• If the numeric value is a fraction with a slash, it is enclosed in brackets, for example: (1/60) s –1.
• When specifying values \u200b\u200bwith maximum deviations, they are enclosed in brackets or put a unit designation after the numerical value of the value and its maximum deviation: (100.0 ± 0.1) kg, 50 g ± 1 g.
• The designations of units included in the product are separated by dots on the middle line (N · m, Pa · s); it is not allowed to use the symbol “x” for this purpose. In typewritten texts it is allowed not to pick up a point or to separate symbols by spaces, if this cannot cause misunderstandings.
• You can use a horizontal line or a slash (only one) as a division mark in the notation. When using a slash, if the denominator is the product of units, it is enclosed in brackets. Correct: W / (m · K), wrong: W / m / K, W / m · K.
• It is allowed to use the notation of units in the form of the product of the notation of units raised to a power (positive and negative): W · m –2 · K –1, A · m 2. When using negative degrees it is not allowed to use a horizontal or slash (division sign).
• It is allowed to use combinations of special characters with letter symbols, for example: ° / s (degrees per second).
• It is not allowed to combine designations and full names of units. Wrong: km / h, correct: km / h.

Multiple units are units that are an integer number of times greater than the basic unit of measurement of a certain physical quantity. The International System of Units (SI) recommends the following prefixes for designations of multiple units:

Binary Prefixes

In the programming and computer-related industries, the same kilo, mega, giga, tera, etc. consoles when applied to values \u200b\u200bmultiple of powers of two (eg bytes) can mean a multiplicity of not 1000 and 1024 \u003d 2 10. What kind of system is used, it should be clear from the context (for example, for the amount of RAM and disk space, a multiplicity of 1024 is used; for channels of communication, a multiplicity of 1000 "kilobits per second").
  1 kilobyte \u003d 1024 1 \u003d 2 10 \u003d 1024 bytes
1 megabyte \u003d 1024 2 \u003d 2 20 \u003d 1 048 576 bytes
  1 gigabyte \u003d 1024 3 \u003d 2 30 \u003d 1 073 741 824 bytes
  1 terabyte \u003d 1024 4 \u003d 2 40 \u003d 1 099 511 627 776 bytes
  1 petabyte \u003d 1024 5 \u003d 2 50 \u003d 1 125 899 906 842 624 bytes
  1 exabyte \u003d 1024 6 \u003d 2 60 \u003d 1 152 921 504 606 846 976 bytes
  1 zettabyte \u003d 1024 7 \u003d 2 70 \u003d 1 180 591 620 717 411 303 424 bytes
  1 year \u003d 1024 8 \u003d 2 80 \u003d 1 208 925 819 614 629 174 706 176 bytes

PS: for binary consoles according to the latest ISO standards, it is proposed to add the ending "bi" (from binary), i.e. "Kibi", "Mibi", "Gibi", respectively, instead of "kilo", "Mega", "Giga", etc.

Prefixes for split units

The fractional units make up a certain proportion (part) of the established unit of measurement of a certain value. The International System of Units (SI) recommends the following prefixes for symbols of subunits:

• Prefixes should be written together with the name of the unit or, respectively, with its designation.
• Using two or more consoles in a row (eg micromillifarad) is not allowed.
• Designations of multiple and partial units of the initial unit raised to a power are formed by adding the corresponding exponent to the designation of a multiple or partial unit of the original unit, and the indicator means raising the power to a power of a multiple or partial unit (together with the prefix). Example: 1 km 2 \u003d (10 3 m) 2 \u003d 10 6 m 2 (and not 10 3 m 2). The names of such units form by appending the prefix to the name of the source unit: a square kilometer (and not a kilo-square meter).
• If a unit is a product or ratio of units, the prefix, or its designation, is usually attached to the designation or designation of the first unit: kPa · s / m (kilopascal-second per meter). Attaching a prefix to the second multiplier of the work or to the denominator is allowed only in justified cases.

The applicability of consoles

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 fractional units of mass, a longitudinal unit of mass - gram (0.001 kg) is used.

Prefixes are limitedly used with units of time: multiple prefixes are not combined with them at all (no one uses “kilosecond”, although this is not formally prohibited), longitudinal prefixes are attached only to the second (millisecond, microsecond, etc.). In accordance with GOST 8.417-2002, the names and designations of the following SI units are not allowed to be used with the prefixes: minute, hour, day (time unit), degree, minute, second (flat angle unit), astronomical unit, diopter and atomic mass unit.

With meters from multiple prefixes, in practice only kilo is used: instead of megameters (Mm), gigameters (Hm), etc., they write “thousands of kilometers”, “millions of kilometers”, and so on; instead of square megameters (Mm 2), they write “millions of square kilometers”.

The capacitance of capacitors is traditionally measured by microfarads and picofarads, but not millifarads or nanofarads (they write 60,000 pF, not 60 nF; 2,000 μF, not 2 mF).

Prefixes corresponding to the exponents that are not divisible by 3 (hecto, deca, deci, centi) are not recommended. Only centimeter (which is the basic unit in the GHS system) and decibel, to a lesser extent decimeter, and also hectare are widely used. In some countries, wine is measured in decaliters.

The formally abolished metric unit is 10 -6 (one millionth) meter. Designation µ. The name and designation were adopted in 1879 by the International Committee for Weights and Measures (CIPM) and re-approved by Resolution 7 at the 9th General Conference on Weights and Weights (CGPM) in 1948. In 1967, the 13th CGPM Conference abolished the micron unit (Resolution 7) and recommended using the term micrometer instead. For this unit of length in the SI system, the term “micrometer” (symbol µm, μm) is adopted. Nevertheless, the term “micron” continues to be widely used in some areas, including the production of semiconductors. This term is often used to describe the size of particles retained by air and water filters, wavelength ranges to which optical devices react, and also in mechanical processing. One of the applications where the use of this unit is currently legitimized by state standards is the description of the quality of wool and other textile goods (see www.ymccoll.com/micron_reports.html).

Micron is often found in the word millimicron \u003d 10 -9 meters or 1/1000 micron fraction. Designation mµ. Like micron, millimicron is an outdated unit. The modern unit of the SI system, which has the same magnitude, is a nanometer (symbol nm, nm).

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1 meter [m] \u003d 1,000,000 micrometer [µm]

Baseline

Converted value

meter exciter petameter terameter hygameter megameter kilometer hectometer decameter decimeter centimeter millimeter micrometer micron nanometer picometer femtometer attometer megaparseque kiloparsec parsec light year astronomical unit league maritime league (Briton) maritime league maritime year astronomical unit maritime league maritime league (martial arts) maritime unit maritimeter (international) mile (statutory) mile (USA, geodesic) mile (Roman) 1000 yards furlong furlong (USA, geodesic) chain chain (USA, geodesic) rope (English rope) gender (US, geodesic) glove pol (English . pol e) fathom, fathom sazhen (United States, geodesic) elbow yard foot foot (United States, geodesic) link link (United States, geodesic), elbow (Brit.), hand finger finger inch inch (US, geodesic) barley grain (English barleycorn ) thousandth micro-inch angstrom atomic unit of length X-unit Fermi Arpan soldering typographical point Twip Elbow (Swedish) Sea fathom (Swedish) Caliber Santimeter Ken Arshin actus (Dr. Rome.) vara de tarea vara conuquera vara castellana elbow Greek Greek. long elbow palm “finger” Planck length classical electron radius Bohr radius of the Earth equatorial radius of the Earth polar distance of the Earth from the Sun to the Sun radius of the Sun light nanosecond light microsecond light millisecond light second light hour light day light week Billion light years Distance from Earth to Moon cable (international) cable (British) cable (US) nautical mile (USA) light-minute rack-mount unit horizontal pitch pixel line pixel line inch (Russian) vershok span foot sazhen oblique sazhen verst land-line mile

Converter feet and inches to meters and back

foot inch

m

Microphones and their specifications

Learn more about length and distance.

General information

Length is the largest dimension of the body. In three-dimensional space, length is usually measured horizontally.

Distance is a value that determines how far the two bodies are separated from each other.

Measuring distance and length

Units of distance and length

In the SI system, length is measured in meters. Derived values, such as kilometer (1000 meters) and centimeter (1/100 meters), are also widely used in the metric system. In countries where the metric system is not used, such as the United States and the United Kingdom, units such as inches, feet, and miles are used.

Distance in physics and biology

In biology and physics, they often measure length much less than one millimeter. For this purpose, a special value, micrometr. One micrometer is equal to 1 × 10⁻⁶ meters. In biology, micrometers measure the size of microorganisms and cells, and in physics, the length of infrared electromagnetic radiation. Micrometer is also called micron and sometimes, especially in English literature, is designated by the Greek letter µ. Other derivatives of the meter are also widely used: nanometers (1 × 10⁻⁹ meters), picometers (1 × 10⁻¹² meters), femtometers (1 × 10 meters and attometers (1 × 10 meters).

Distance in navigation

Shipping uses nautical miles. One nautical mile is equal to 1852 meters. Initially, it was measured as an arc in one minute along the meridian, that is, 1 / (60 × 180) meridian. This made it easier to calculate latitude, since 60 nautical miles equaled one degree of latitude. When distance is measured in nautical miles, speed is often measured in nautical knots. One nautical node is equal to the speed of one nautical mile per hour.

Distance in astronomy

In astronomy, large distances are measured, therefore special values \u200b\u200bare taken to facilitate calculations.

Astronomical unit   (a. e., au) is equal to 149,597,870,700 meters. The value of one astronomical unit is a constant, that is, a constant value. It is believed that the Earth is at a distance of one astronomical unit from the Sun.

Light year   equals 10,000,000,000,000 or 10¹³ kilometers. This is the distance that light travels in a vacuum in one Julian year. This value is used in popular science literature more often than in physics and astronomy.

Parsec is approximately equal to 30,856,775,814,671,900 meters or approximately 3.09 × 10¹³ kilometers. One parsec is the distance from the Sun to another astronomical object, such as a planet, star, moon, or an asteroid, with an angle of one arc second. One angular second is 1/3600 degrees, or approximately 4.8481368 mrad in radians. Parsec can be calculated using parallax - the effect of a visible change in body position, depending on the point of observation. When measuring, plot the E1A2 segment (in the illustration) from the Earth (point E1) to a star or other astronomical object (point A2). Six months later, when the Sun is on the other side of the Earth, a new segment of E2A1 is being laid from the new position of the Earth (point E2) to the new position in space of the same astronomical object (point A1). In this case, the Sun will be located at the intersection of these two segments, at point S. The length of each of the E1S and E2S segments is equal to one astronomical unit. If you put the segment through point S, perpendicular to E1E2, it passes through the intersection point of segments E1A2 and E2A1, I. The distance from the Sun to point I is SI, it is equal to one parsek when the angle between segments A1I and A2I is two angular seconds.

On the picture:

• A1, A2: apparent star position
• E1, E2: Earth's position
• S: position of the sun
• I: intersection
• IS \u003d 1 parsec
• ∠P or ∠XIA2: parallax angle
• ∠P \u003d 1 angular second

Other units

League   - an obsolete unit of length, used previously in many countries. In some places it is still used, for example, on the Yucatan Peninsula and in rural areas of Mexico. This is the distance that a person travels in an hour. Nautical League - three nautical miles, about 5.6 kilometers. Lier is a unit roughly equal to the league. In English, both leagues and leagues are called alike, league. In literature, leagues are sometimes found in the titles of books, such as “20,000 leagues under the sea” - a famous novel by Jules Verne.

Cubit   - old value equal to the distance from the tip of the middle finger to the elbow. This value was widespread in the ancient world, in the Middle Ages, and until the new time.

Yard   used in the British imperial system of measures and is equal to three feet, or 0.9144 meters. In some countries, such as Canada, where the metric system is adopted, yards are used to measure the fabric and length of swimming pools and sports fields and playgrounds, such as golf courses and football.

Meter definition

The definition of the meter has changed several times. Initially, the meter was defined as 1/10 000 000 distance from the North Pole to the equator. Later, the meter was equal to the length of the platinum-iridium standard. Later, the meter was equated to the wavelength of the orange line of the electromagnetic spectrum of the пKr krypton atom in vacuum multiplied by 1 650 763.73. Today, the meter is defined as the distance traveled by light in a vacuum in 1/299 792 458 seconds.

Calculations

In geometry, the distance between two points, A and B, with coordinates A (x₁, y₁) and B (x₂, y₂) is calculated by the formula:

Calculations for the transfer of units in the converter " Length and distance converter»Are performed using the unitconversion.org functions.

Converter of length and distance Converter of mass Converter of volume measures of bulk products and food Converter of area Converter of volume and units of measure in culinary recipes Temperature converter Converter of pressure, mechanical stress, Young's module Energy converter and work Converter of power linear converter of time Flat converter of converter thermal efficiency and fuel efficiency Number converter in various numeral systems and Exchange Rates Women's clothing and shoes sizes Men's clothing and shoes sizes Angular speed and rotational speed converter Acceleration converter Angular acceleration converter Density converter Specific volume converter Inertia converter Moment converter Power converter Specific calorific value converter (in mass) Converter of energy density and specific heat of combustion of fuel (by volume) Temperature difference converter Converter of thermal expansion Converter thermal resistance Co erter thermal conductivity converter specific heat converter radiant exposure and power thermal radiation converter heat flux density converter heat transfer coefficient converter volumetric flow converter mass flow converter molar flow rate converter mass flux density converter molar concentration converter mass concentration in the solution of dynamic (absolute) viscosity Converter Converter kinematic viscosity Surface Tension Converter testability Capacity and vapor transfer rate converter Sound level converter Microphone sensitivity converter Sound pressure level converter (SPL) Sound pressure level converter with selectable reference pressure Brightness converter Light intensity converter Illumination converter Resolution converter in computer graphics Frequency and wavelength converter Optical power in diopters and focal length Optical power in diopters and magnification of the lens (×) Converter of electric charge Converter linear flat tnosti charge converter surface charge density converter volumetric charge density of the electric current converter converter linear current density converter surface current density converter electric field strength of converter electrostatic capacity and a voltage converter in electrical resistance converter electrical resistivity converter electric conductivity converter conductivity Electric capacitance converter inductance converter Ameri anskogo gauge wires levels in dBm (dBm or dBm), dBV (dBV) Watts et al. units Converter magnetomotive force Converter magnetic field intensity Converter magnetic flux Converter magnetic induction Radiation. Ionized radiation absorbed dose rate converter Radioactivity. Converter of radioactive decay Radiation. Exposure dose converter Radiation. Absorbed dose converter Converter of decimal prefixes Data transfer Unit of typography and image processing units Converter of timber volume units Calculation of molar mass Periodic system of chemical elements DI Mendeleeva

1 meter [m] \u003d 1,000,000 micrometer [µm]

Baseline

Converted value

meter exciter petameter terameter hygameter megameter kilometer hectometer decameter decimeter centimeter millimeter micrometer micron nanometer picometer femtometer attometer megaparseque kiloparsec parsec light year astronomical unit league maritime league (Briton) maritime league maritime year astronomical unit maritime league maritime league (martial arts) maritime unit maritimeter (international) mile (statutory) mile (USA, geodesic) mile (Roman) 1000 yards furlong furlong (USA, geodesic) chain chain (USA, geodesic) rope (English rope) gender (US, geodesic) glove pol (English . pol e) fathom, fathom sazhen (United States, geodesic) elbow yard foot foot (United States, geodesic) link link (United States, geodesic), elbow (Brit.), hand finger finger inch inch (US, geodesic) barley grain (English barleycorn ) thousandth micro-inch angstrom atomic unit of length X-unit Fermi Arpan soldering typographical point Twip Elbow (Swedish) Sea fathom (Swedish) Caliber Santimeter Ken Arshin actus (Dr. Rome.) vara de tarea vara conuquera vara castellana elbow Greek Greek. long elbow palm “finger” Planck length classical electron radius Bohr radius of the Earth equatorial radius of the Earth polar distance of the Earth from the Sun to the Sun radius of the Sun light nanosecond light microsecond light millisecond light second light hour light day light week Billion light years Distance from Earth to Moon cable (international) cable (British) cable (US) nautical mile (USA) light-minute rack-mount unit horizontal pitch pixel line pixel line inch (Russian) vershok span foot sazhen oblique sazhen verst land-line mile

Converter feet and inches to meters and back

foot inch

m

Learn more about length and distance.

General information

Length is the largest dimension of the body. In three-dimensional space, length is usually measured horizontally.

Distance is a value that determines how far the two bodies are separated from each other.

Measuring distance and length

Units of distance and length

In the SI system, length is measured in meters. Derived values, such as kilometer (1000 meters) and centimeter (1/100 meters), are also widely used in the metric system. In countries where the metric system is not used, such as the United States and the United Kingdom, units such as inches, feet, and miles are used.

Distance in physics and biology

In biology and physics, they often measure length much less than one millimeter. For this purpose, a special value, micrometr. One micrometer is equal to 1 × 10⁻⁶ meters. In biology, micrometers measure the size of microorganisms and cells, and in physics, the length of infrared electromagnetic radiation. Micrometer is also called micron and sometimes, especially in English literature, is designated by the Greek letter µ. Other derivatives of the meter are also widely used: nanometers (1 × 10⁻⁹ meters), picometers (1 × 10⁻¹² meters), femtometers (1 × 10 meters and attometers (1 × 10 meters).

Distance in navigation

Shipping uses nautical miles. One nautical mile is equal to 1852 meters. Initially, it was measured as an arc in one minute along the meridian, that is, 1 / (60 × 180) meridian. This made it easier to calculate latitude, since 60 nautical miles equaled one degree of latitude. When distance is measured in nautical miles, speed is often measured in nautical knots. One nautical node is equal to the speed of one nautical mile per hour.

Distance in astronomy

In astronomy, large distances are measured, therefore special values \u200b\u200bare taken to facilitate calculations.

Astronomical unit   (a. e., au) is equal to 149,597,870,700 meters. The value of one astronomical unit is a constant, that is, a constant value. It is believed that the Earth is at a distance of one astronomical unit from the Sun.

Light year   equals 10,000,000,000,000 or 10¹³ kilometers. This is the distance that light travels in a vacuum in one Julian year. This value is used in popular science literature more often than in physics and astronomy.

Parsec is approximately equal to 30,856,775,814,671,900 meters or approximately 3.09 × 10¹³ kilometers. One parsec is the distance from the Sun to another astronomical object, such as a planet, star, moon, or an asteroid, with an angle of one arc second. One angular second is 1/3600 degrees, or approximately 4.8481368 mrad in radians. Parsec can be calculated using parallax - the effect of a visible change in body position, depending on the point of observation. When measuring, plot the E1A2 segment (in the illustration) from the Earth (point E1) to a star or other astronomical object (point A2). Six months later, when the Sun is on the other side of the Earth, a new segment of E2A1 is being laid from the new position of the Earth (point E2) to the new position in space of the same astronomical object (point A1). In this case, the Sun will be located at the intersection of these two segments, at point S. The length of each of the E1S and E2S segments is equal to one astronomical unit. If you put the segment through point S, perpendicular to E1E2, it passes through the intersection point of segments E1A2 and E2A1, I. The distance from the Sun to point I is SI, it is equal to one parsek when the angle between segments A1I and A2I is two angular seconds.

On the picture:

• A1, A2: apparent star position
• E1, E2: Earth's position
• S: position of the sun
• I: intersection
• IS \u003d 1 parsec
• ∠P or ∠XIA2: parallax angle
• ∠P \u003d 1 angular second

Other units

League   - an obsolete unit of length, used previously in many countries. In some places it is still used, for example, on the Yucatan Peninsula and in rural areas of Mexico. This is the distance that a person travels in an hour. Nautical League - three nautical miles, about 5.6 kilometers. Lier is a unit roughly equal to the league. In English, both leagues and leagues are called alike, league. In literature, leagues are sometimes found in the titles of books, such as “20,000 leagues under the sea” - a famous novel by Jules Verne.

Cubit   - old value equal to the distance from the tip of the middle finger to the elbow. This value was widespread in the ancient world, in the Middle Ages, and until the new time.

Yard   used in the British imperial system of measures and is equal to three feet, or 0.9144 meters. In some countries, such as Canada, where the metric system is adopted, yards are used to measure the fabric and length of swimming pools and sports fields and playgrounds, such as golf courses and football.

Meter definition

The definition of the meter has changed several times. Initially, the meter was defined as 1/10 000 000 distance from the North Pole to the equator. Later, the meter was equal to the length of the platinum-iridium standard. Later, the meter was equated to the wavelength of the orange line of the electromagnetic spectrum of the пKr krypton atom in vacuum multiplied by 1 650 763.73. Today, the meter is defined as the distance traveled by light in a vacuum in 1/299 792 458 seconds.

Calculations

In geometry, the distance between two points, A and B, with coordinates A (x₁, y₁) and B (x₂, y₂) is calculated by the formula:

Calculations for the transfer of units in the converter " Length and distance converter»Are performed using the unitconversion.org functions.