Как сокращенно амперы пишутся

Множители и приставки для образования кратных и дробных единиц

Сокращённые обозначения эл.величин

Как не запутаться в расчётах?

Если будет допущена ошибка и выбран элемент с неверным номиналом, то собранное устройство будет неправильно работать или иметь другие характеристики.

Такая ситуация на практике не редкость, так как иногда на корпусах радиоэлементов указывают величину ёмкости в нанофарадах (нФ), а на принципиальной схеме ёмкости конденсаторов, как правило, указаны в микрофарадах (мкФ) и пикофарадах (пФ). Это вводит многих начинающих радиолюбителей в заблуждение и как следствие тормозит сборку электронного устройства.

Чтобы данной ситуации не происходило нужно научиться простым расчётам.

Чтобы не запутаться в микрофарадах, нанофарадах, пикофарадах нужно ознакомиться с таблицей размерности. Уверен, она вам ещё не раз пригодиться.

Данная таблица включает в себя десятичные кратные и дробные (дольные) приставки. Международная система единиц, которая носит сокращённое название СИ, включает шесть кратных (дека, гекто, кило, мега, гига, тера) и восемь дольных приставок (деци, санти, милли, микро, нано, пико, фемто, атто). Многие из этих приставок давно используются в электронике.

Как пользоваться таблицей?

Как видим из таблицы, разница между многими приставками составляет ровно 1000. Так, например, такое правило действует между кратными величинами, начиная с приставки кило-.

• Кило  — 1000

• Мега  — 1 000 000

• Гига – 1 000 000 000

• Тера – 1 000 000 000 000

Так, если рядом с обозначением резистора написано 1 Мом (1 Мегаом), то его сопротивление составит – 1000000 (1 миллион) Ом. Если же имеется резистор с номинальным сопротивлением 1 кОм (1 килоом), то в Омах это будет  1000 (1 тысяча) Ом.

Для дольных или по-другому дробных величин ситуация похожа, только происходит не увеличение численного значения, а его уменьшение.

Чтобы не запутаться в микрофарадах, нанофарадах, пикофарадах, нужно запомнить одно простое правило. Нужно понимать, что милли, микро, нано и пико – все они отличаются ровно на 1000. То есть если вам говорят 47 микрофарад, то это значит, что в нанофарадах это будет в 1000 раз больше – 47000 нанофарад. В пикофарадах это уже будет ещё на 1000 раз больше – 47000000 пикофарад. Как видим, разница между 1 микрофарадой и 1 пикофарадой составляет 1 000000 раз.

Также на практике иногда требуется знать значение в микрофарадах, а значение ёмкости указано в нанофарадах. Так если ёмкость конденсатора 1 нанофарада, то в микрофарадах это будет 0,001 мкф. Если ёмкость 0,01 мкф., то в пикофарадах это будет 10000 пФ, а в нанофарадах, соответственно, 10 нФ.

Приставки, обозначающие размерность величины служат для сокращённой записи. Согласитесь проще написать 1мА, чем 0,001 Ампер или, например, 400 мкГн, чем 0,0004 Генри.

В показанной ранее таблице также есть сокращённое обозначение приставки. Так, чтобы не писать Мега, пишут только букву М. За приставкой обычно следует сокращённое обозначение электрической величины. Например, слово Ампер не пишут, а указывают только букву А. Также поступают при сокращении записи единицы измерения ёмкости Фарада. В этом случае пишется только буква Ф.

Наравне с сокращённой записью на русском языке, которая часто используется в старой радиоэлектронной литературе, существует и международная сокращённая запись приставок. Она также указана в таблице.

Главная &raquo Радиоэлектроника для начинающих &raquo Текущая страница

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• Измерение сопротивления цифровым мультиметром.

• «Мультирозетка». Собираем многофункциональную розетку.

• Монтажный инструмент начинающего радиолюбителя.

Морфологические и синтаксические свойства

ам—пе́р

Существительное, неодушевлённое, мужской род, 2-е склонение (тип склонения 1a(2) по классификации А. А. Зализняка).

Встречается также вариант написания: А.

Корень: -ампер- [Тихонов, 1996].

Произношение

• МФА: ед. ч. [ɐm⁽ʲ⁾ˈpʲer], мн. ч. [ɐm⁽ʲ⁾ˈpʲerɨ]

Семантические свойства

Значение

1. физ. единица измерения силы электрического тока в системе СИ ◆ Сила тока в этом проводнике достигает десяти ампер.

Синонимы

Гиперонимы

Гипонимы

Родственные слова

Ближайшее родство
имена собственные: Ампер пр. существительные: ампераж, амперметр, вольт-ампер, килоампер, килоамперметр, киловольт-ампер, мегаампер, микроампер, микроамперметр, миллиампер, миллиамперметр, наноампер, наноамперметр, пикоампер, пикоамперметр прилагательные: многоамперный

Этимология

Назван в честь французского физика Андре Ампера.

Фразеологизмы и устойчивые сочетания

Перевод

Библиография

Для улучшения этой статьи желательно: Добавить необходимые разделы в «Семантические свойства» (Синонимы, Антонимы, Гиперонимы, Гипонимы)

Морфологические и синтаксические свойства

ам—пер

Существительное, мужской род, склонение 7.

Корень: -ампер-.

Произношение

Семантические свойства

Значение

1. ампер ◆ Ампер е единицата за измерване на електричния ток.

Синонимы

Гиперонимы

Гипонимы

Родственные слова

Этимология

Назван в честь французского физика Андре Ампера.

Морфологические и синтаксические свойства

ам—пер

Существительное, мужской род.

Корень: -ампер-.

Произношение

Семантические свойства

Значение

1. ампер ◆ Отсутствует пример употребления (см. рекомендации).

Синонимы

Гиперонимы

Гипонимы

Родственные слова

Этимология

Назван в честь французского физика Андре Ампера.

Морфологические и синтаксические свойства

ам—пер

Существительное, неодушевлённое, мужской род.

Корень: -ампер-.

Произношение

Семантические свойства

Значение

1. ампер ◆ Ампер — одиниця величини електричного струму.

Синонимы

Гиперонимы

Гипонимы

Родственные слова

Этимология

Назван в честь французского физика Андре Ампера.

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From Wikipedia, the free encyclopedia

ampere
Demonstration model of a moving iron ammeter. As the current through the coil increases, the plunger is drawn further into the coil and the pointer deflects to the right.
General information
Unit system	SI
Unit of	electric current
Symbol	A
Named after	André-Marie Ampère

The ampere (, ;^[1][2][3] symbol: A),^[4] often shortened to amp,^[5] is the unit of electric current in the International System of Units (SI). One ampere is equal to 1 coulomb or 6.241509074×10¹⁸ electrons worth of charge moving past a point in a second.^[6][7][8] It is named after French mathematician and physicist André-Marie Ampère (1775–1836), considered the father of electromagnetism along with Danish physicist Hans Christian Ørsted.

As of the 2019 redefinition of the SI base units, the ampere is defined by fixing the elementary charge e to be exactly 1.602176634×10⁻¹⁹ C (coulomb),^[6][9] which means an ampere is an electrical current equivalent to 10¹⁹ elementary charges moving every 1.602176634 seconds or 6.241509074×10¹⁸ elementary charges moving in a second. Prior to the redefinition the ampere was defined as the current that would need to be passed through 2 parallel wires 1 metre apart to produce a magnetic force of 2×10⁻⁷ newtons per metre.

The earlier CGS system had two definitions of current, one essentially the same as the SI’s and the other using Coulomb’s law as a fundamental relationship, with the unit of charge defined by measuring the force between two charged metal plates. The ampere was then defined as one coulomb of charge per second.^[10] In SI, the unit of charge, the coulomb, is defined as the charge carried by one ampere during one second.

History[edit]

The ampere is named for French physicist and mathematician André-Marie Ampère (1775–1836), who studied electromagnetism and laid the foundation of electrodynamics. In recognition of Ampère’s contributions to the creation of modern electrical science, an international convention, signed at the 1881 International Exposition of Electricity, established the ampere as a standard unit of electrical measurement for electric current.

The ampere was originally defined as one tenth of the unit of electric current in the centimetre–gram–second system of units. That unit, now known as the abampere, was defined as the amount of current that generates a force of two dynes per centimetre of length between two wires one centimetre apart.^[11] The size of the unit was chosen so that the units derived from it in the MKSA system would be conveniently sized.

The «international ampere» was an early realization of the ampere, defined as the current that would deposit 0.001118 grams of silver per second from a silver nitrate solution.^[12] Later, more accurate measurements revealed that this current is 0.99985 A.

Since power is defined as the product of current and voltage, the ampere can alternatively be expressed in terms of the other units using the relationship I = P/V, and thus 1 A = 1 W/V. Current can be measured by a multimeter, a device that can measure electrical voltage, current, and resistance.

Former definition in the SI[edit]

Until 2019, the SI defined the ampere as follows:

The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one metre apart in vacuum, would produce between these conductors a force equal to 2×10⁻⁷ newtons per metre of length.^{[13]: 113  [14]}

Ampère’s force law^[15][16] states that there is an attractive or repulsive force between two parallel wires carrying an electric current. This force is used in the formal definition of the ampere.

The SI unit of charge, the coulomb, was then defined as «the quantity of electricity carried in 1 second by a current of 1 ampere».^[13]: 144 Conversely, a current of one ampere is one coulomb of charge going past a given point per second:

In general, charge Q was determined by steady current I flowing for a time t as Q = It.

This definition of the ampere was most accurately realised using a Kibble balance, but in practice the unit was maintained via Ohm’s law from the units of electromotive force and resistance, the volt and the ohm, since the latter two could be tied to physical phenomena that are relatively easy to reproduce, the Josephson effect and the quantum Hall effect, respectively.^[17]

Techniques to establish the realisation of an ampere had a relative uncertainty of approximately a few parts in 10⁷, and involved realisations of the watt, the ohm and the volt.^[17]

Present definition[edit]

The 2019 redefinition of the SI base units defined the ampere by taking the fixed numerical value of the elementary charge e to be 1.602 176 634 × 10⁻¹⁹ when expressed in the unit C, which is equal to A⋅s, where the second is defined in terms of ∆ν_Cs, the unperturbed ground state hyperfine transition frequency of the caesium-133 atom.^[18]

The SI unit of charge, the coulomb, «is the quantity of electricity carried in 1 second by a current of 1 ampere».^[19] Conversely, a current of one ampere is one coulomb of charge going past a given point per second:

In general, charge Q is determined by steady current I flowing for a time t as Q = I t.

Constant, instantaneous and average current are expressed in amperes (as in «the charging current is 1.2 A») and the charge accumulated (or passed through a circuit) over a period of time is expressed in coulombs (as in «the battery charge is 30000 C«). The relation of the ampere (C/s) to the coulomb is the same as that of the watt (J/s) to the joule.

Units derived from the ampere[edit]

The international system of units (SI) is based on 7 SI base units the second, metre, kilogram, kelvin, ampere, mole, and candela representing 7 fundamental types of physical quantity, or «dimensions», (time, length, mass, temperature, electrical current, amount of substance, and luminous intensity respectively) with all other SI units being defined using these. These SI derived units can either be given special names e.g. watt, volt, lux, etc. or defined in terms of others, e.g. metre per second. The units with special names derived from the ampere are:

Quantity	Unit	Symbol	Meaning	In SI base units
Electric charge	coulomb	C	ampere second	A⋅s
Electric potential difference	volt	V	joule per coulomb	kg⋅m2⋅s−3⋅A−1
Electrical resistance	ohm	Ω	volt per ampere	kg⋅m2⋅s−3⋅A−2
Electrical conductance	siemens	S	ampere per volt or inverse ohm	s3⋅A2⋅kg−1⋅m−2
Electrical inductance	henry	H	ohm second	kg⋅m2⋅s−2⋅A−2
Electrical capacitance	farad	F	coulomb per volt	s4⋅A2⋅kg−1⋅m−2
Magnetic flux	weber	Wb	volt second	kg⋅m2⋅s−2⋅A−1
Magnetic flux density	tesla	T	weber per square metre	kg⋅s−2⋅A−1

There are also some SI units that are frequently used in the context of electrical engineering and electrical appliances, but can be defined independently of the ampere, notably the hertz, joule, watt, candela, lumen, and lux.

SI prefixes[edit]

Like other SI units, the ampere can be modified by adding a prefix that multiplies it by a power of 10.

SI multiples of ampere (A)

Submultiples		Multiples
Value	SI symbol	Name	Value	SI symbol	Name
10−1 A	dA	deciampere	101 A	daA	decaampere
10−2 A	cA	centiampere	102 A	hA	hectoampere
10−3 A	mA	milliampere	103 A	kA	kiloampere
10−6 A	µA	microampere	106 A	MA	megaampere
10−9 A	nA	nanoampere	109 A	GA	gigaampere
10−12 A	pA	picoampere	1012 A	TA	teraampere
10−15 A	fA	femtoampere	1015 A	PA	petaampere
10−18 A	aA	attoampere	1018 A	EA	exaampere
10−21 A	zA	zeptoampere	1021 A	ZA	zettaampere
10−24 A	yA	yoctoampere	1024 A	YA	yottaampere
10−27 A	rA	rontoampere	1027 A	RA	ronnaampere
10−30 A	qA	quectoampere	1030 A	QA	quettaampere

See also[edit]

• Ammeter
• Ampacity (current-carrying capacity)
• Electric current
• Electric shock
• Hydraulic analogy
• Magnetic constant
• Orders of magnitude (current)

References[edit]

External links[edit]

• The NIST Reference on Constants, Units, and Uncertainty
• NIST Definition of ampere and μ₀

From Wikipedia, the free encyclopedia

ampere
Demonstration model of a moving iron ammeter. As the current through the coil increases, the plunger is drawn further into the coil and the pointer deflects to the right.
General information
Unit system	SI
Unit of	electric current
Symbol	A
Named after	André-Marie Ampère

The ampere (, ;^[1][2][3] symbol: A),^[4] often shortened to amp,^[5] is the unit of electric current in the International System of Units (SI). One ampere is equal to 1 coulomb or 6.241509074×10¹⁸ electrons worth of charge moving past a point in a second.^[6][7][8] It is named after French mathematician and physicist André-Marie Ampère (1775–1836), considered the father of electromagnetism along with Danish physicist Hans Christian Ørsted.

As of the 2019 redefinition of the SI base units, the ampere is defined by fixing the elementary charge e to be exactly 1.602176634×10⁻¹⁹ C (coulomb),^[6][9] which means an ampere is an electrical current equivalent to 10¹⁹ elementary charges moving every 1.602176634 seconds or 6.241509074×10¹⁸ elementary charges moving in a second. Prior to the redefinition the ampere was defined as the current that would need to be passed through 2 parallel wires 1 metre apart to produce a magnetic force of 2×10⁻⁷ newtons per metre.

The earlier CGS system had two definitions of current, one essentially the same as the SI’s and the other using Coulomb’s law as a fundamental relationship, with the unit of charge defined by measuring the force between two charged metal plates. The ampere was then defined as one coulomb of charge per second.^[10] In SI, the unit of charge, the coulomb, is defined as the charge carried by one ampere during one second.

History[edit]

The ampere is named for French physicist and mathematician André-Marie Ampère (1775–1836), who studied electromagnetism and laid the foundation of electrodynamics. In recognition of Ampère’s contributions to the creation of modern electrical science, an international convention, signed at the 1881 International Exposition of Electricity, established the ampere as a standard unit of electrical measurement for electric current.

The ampere was originally defined as one tenth of the unit of electric current in the centimetre–gram–second system of units. That unit, now known as the abampere, was defined as the amount of current that generates a force of two dynes per centimetre of length between two wires one centimetre apart.^[11] The size of the unit was chosen so that the units derived from it in the MKSA system would be conveniently sized.

The «international ampere» was an early realization of the ampere, defined as the current that would deposit 0.001118 grams of silver per second from a silver nitrate solution.^[12] Later, more accurate measurements revealed that this current is 0.99985 A.

Since power is defined as the product of current and voltage, the ampere can alternatively be expressed in terms of the other units using the relationship I = P/V, and thus 1 A = 1 W/V. Current can be measured by a multimeter, a device that can measure electrical voltage, current, and resistance.

Former definition in the SI[edit]

Until 2019, the SI defined the ampere as follows:

The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed one metre apart in vacuum, would produce between these conductors a force equal to 2×10⁻⁷ newtons per metre of length.^{[13]: 113  [14]}

Ampère’s force law^[15][16] states that there is an attractive or repulsive force between two parallel wires carrying an electric current. This force is used in the formal definition of the ampere.

The SI unit of charge, the coulomb, was then defined as «the quantity of electricity carried in 1 second by a current of 1 ampere».^[13]: 144 Conversely, a current of one ampere is one coulomb of charge going past a given point per second:

In general, charge Q was determined by steady current I flowing for a time t as Q = It.

This definition of the ampere was most accurately realised using a Kibble balance, but in practice the unit was maintained via Ohm’s law from the units of electromotive force and resistance, the volt and the ohm, since the latter two could be tied to physical phenomena that are relatively easy to reproduce, the Josephson effect and the quantum Hall effect, respectively.^[17]

Techniques to establish the realisation of an ampere had a relative uncertainty of approximately a few parts in 10⁷, and involved realisations of the watt, the ohm and the volt.^[17]

Present definition[edit]

The 2019 redefinition of the SI base units defined the ampere by taking the fixed numerical value of the elementary charge e to be 1.602 176 634 × 10⁻¹⁹ when expressed in the unit C, which is equal to A⋅s, where the second is defined in terms of ∆ν_Cs, the unperturbed ground state hyperfine transition frequency of the caesium-133 atom.^[18]

The SI unit of charge, the coulomb, «is the quantity of electricity carried in 1 second by a current of 1 ampere».^[19] Conversely, a current of one ampere is one coulomb of charge going past a given point per second:

In general, charge Q is determined by steady current I flowing for a time t as Q = I t.

Constant, instantaneous and average current are expressed in amperes (as in «the charging current is 1.2 A») and the charge accumulated (or passed through a circuit) over a period of time is expressed in coulombs (as in «the battery charge is 30000 C«). The relation of the ampere (C/s) to the coulomb is the same as that of the watt (J/s) to the joule.

Units derived from the ampere[edit]

The international system of units (SI) is based on 7 SI base units the second, metre, kilogram, kelvin, ampere, mole, and candela representing 7 fundamental types of physical quantity, or «dimensions», (time, length, mass, temperature, electrical current, amount of substance, and luminous intensity respectively) with all other SI units being defined using these. These SI derived units can either be given special names e.g. watt, volt, lux, etc. or defined in terms of others, e.g. metre per second. The units with special names derived from the ampere are:

Quantity	Unit	Symbol	Meaning	In SI base units
Electric charge	coulomb	C	ampere second	A⋅s
Electric potential difference	volt	V	joule per coulomb	kg⋅m2⋅s−3⋅A−1
Electrical resistance	ohm	Ω	volt per ampere	kg⋅m2⋅s−3⋅A−2
Electrical conductance	siemens	S	ampere per volt or inverse ohm	s3⋅A2⋅kg−1⋅m−2
Electrical inductance	henry	H	ohm second	kg⋅m2⋅s−2⋅A−2
Electrical capacitance	farad	F	coulomb per volt	s4⋅A2⋅kg−1⋅m−2
Magnetic flux	weber	Wb	volt second	kg⋅m2⋅s−2⋅A−1
Magnetic flux density	tesla	T	weber per square metre	kg⋅s−2⋅A−1

There are also some SI units that are frequently used in the context of electrical engineering and electrical appliances, but can be defined independently of the ampere, notably the hertz, joule, watt, candela, lumen, and lux.

SI prefixes[edit]

Like other SI units, the ampere can be modified by adding a prefix that multiplies it by a power of 10.

SI multiples of ampere (A)

Submultiples		Multiples
Value	SI symbol	Name	Value	SI symbol	Name
10−1 A	dA	deciampere	101 A	daA	decaampere
10−2 A	cA	centiampere	102 A	hA	hectoampere
10−3 A	mA	milliampere	103 A	kA	kiloampere
10−6 A	µA	microampere	106 A	MA	megaampere
10−9 A	nA	nanoampere	109 A	GA	gigaampere
10−12 A	pA	picoampere	1012 A	TA	teraampere
10−15 A	fA	femtoampere	1015 A	PA	petaampere
10−18 A	aA	attoampere	1018 A	EA	exaampere
10−21 A	zA	zeptoampere	1021 A	ZA	zettaampere
10−24 A	yA	yoctoampere	1024 A	YA	yottaampere
10−27 A	rA	rontoampere	1027 A	RA	ronnaampere
10−30 A	qA	quectoampere	1030 A	QA	quettaampere

See also[edit]

• Ammeter
• Ampacity (current-carrying capacity)
• Electric current
• Electric shock
• Hydraulic analogy
• Magnetic constant
• Orders of magnitude (current)

References[edit]

External links[edit]

• The NIST Reference on Constants, Units, and Uncertainty
• NIST Definition of ampere and μ₀

• Андрэ-Мари Ампер ввел в физику понятие «электрический ток», он так же в 1830 году ввел такой научный оборот, как «кибернетика», а в механике именно ему принадлежит термин «кинематика».

• Андрэ-Мари Ампер был очень разноплановым и разносторонне развитым ученым, некоторые его исследования касались таких смежных с физикой наук, как химия, ботаника и даже философия! И именно А.М.Ампер изобрел такие важные и полезные для людей устройства, как электромагнитный телеграф и коммутатор.

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