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Index Ohm

The ohm (symbol: Ω) is the SI derived unit of electrical resistance, named after German physicist Georg Simon Ohm. [1]

62 relations: Abohm, Admittance, Alt code, Alternating current, Ampere, Annalen der Physik, ASCII, British Science Association, Centimetre–gram–second system of units, Charles Tilston Bright, Coherence (units of measurement), Coulomb, Dimensional analysis, Electrical impedance, Electrical resistance and conductance, Electrical resistivity and conductivity, Electrochemistry, Electromotive force, Electronic color code, Farad, General Conference on Weights and Measures, Georg Ohm, History of measurement, IEEE Std 260.1-2004, Integral, International Committee for Weights and Measures, International Electrical Congress, James Clerk Maxwell, Johann Christian Poggendorff, Josiah Latimer Clark, Joule, Joule heating, Kilogram, Letter and digit code, Letterlike Symbols, Linearity, Metre, Metrology, Multiplicative inverse, Ohm's law, Omega, Orders of magnitude (resistance), Philosophical Magazine, Power (physics), Quantum Hall effect, Resistor, Second, SI base unit, SI derived unit, Siemens (unit), ..., Siemens mercury unit, Statohm, Symbol (typeface), The Electrician, Thermistor, Unicode, Volt, Voltage, Watt, Werner von Siemens, William Henry Preece, William Thomson, 1st Baron Kelvin. Expand index (12 more) »


The abohm is the basic unit of electrical resistance in the emu-cgs ''(centimeter-gram-second)'' system of units (emu stands for "electromagnetic units").

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In electrical engineering, admittance is a measure of how easily a circuit or device will allow a current to flow.

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Alt code

On IBM compatible personal computers, many characters not directly associated with a key can be entered using the Alt Numpad input method or Alt code: pressing and holding the ''Alt'' key while typing the number identifying the character with the keyboard's numeric keypad.

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Alternating current

Alternating current (AC) is an electric current which periodically reverses direction, in contrast to direct current (DC) which flows only in one direction.

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The ampere (symbol: A), often shortened to "amp",SI supports only the use of symbols and deprecates the use of abbreviations for units.

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Annalen der Physik

Annalen der Physik (English: Annals of Physics) is one of the oldest scientific journals on physics and has been published since 1799.

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ASCII, abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication.

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British Science Association

The British Science Association (BSA) is a charity and learned society founded in 1831 to aid in the promotion and development of science.

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Centimetre–gram–second system of units

The centimetre–gram–second system of units (abbreviated CGS or cgs) is a variant of the metric system based on the centimetre as the unit of length, the gram as the unit of mass, and the second as the unit of time.

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Charles Tilston Bright

Sir Charles Tilston Bright (8 June 1832 – 3 May 1888) was a British electrical engineer who oversaw the laying of the first transatlantic telegraph cable in 1858, for which work he was knighted.

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Coherence (units of measurement)

A coherent system of units is based on a system of quantities in such a way that the equations between the numerical values expressed in coherent units have exactly the same form, including numerical factors, as the corresponding equations between the quantities.

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The coulomb (symbol: C) is the International System of Units (SI) unit of electric charge.

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Dimensional analysis

In engineering and science, dimensional analysis is the analysis of the relationships between different physical quantities by identifying their base quantities (such as length, mass, time, and electric charge) and units of measure (such as miles vs. kilometers, or pounds vs. kilograms) and tracking these dimensions as calculations or comparisons are performed.

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Electrical impedance

Electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied.

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Electrical resistance and conductance

The electrical resistance of an electrical conductor is a measure of the difficulty to pass an electric current through that conductor.

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Electrical resistivity and conductivity

Electrical resistivity (also known as resistivity, specific electrical resistance, or volume resistivity) is a fundamental property that quantifies how strongly a given material opposes the flow of electric current.

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Electrochemistry is the branch of physical chemistry that studies the relationship between electricity, as a measurable and quantitative phenomenon, and identifiable chemical change, with either electricity considered an outcome of a particular chemical change or vice versa.

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Electromotive force

Electromotive force, abbreviated emf (denoted \mathcal and measured in volts), is the electrical intensity or "pressure" developed by a source of electrical energy such as a battery or generator.

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Electronic color code

An electronic color code is used to indicate the values or ratings of electronic components, usually for resistors, but also for capacitors, inductors, diodes and others.

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The farad (symbol: F) is the SI derived unit of electrical capacitance, the ability of a body to store an electrical charge.

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General Conference on Weights and Measures

The General Conference on Weights and Measures (Conférence générale des poids et mesures – CGPM) is the supreme authority of the International Bureau of Weights and Measures (Bureau international des poids et mesures – BIPM), the inter-governmental organization established in 1875 under the terms of the Metre Convention (Convention du Mètre) through which Member States act together on matters related to measurement science and measurement standards.

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Georg Ohm

Georg Simon Ohm (16 March 1789 – 6 July 1854) was a German physicist and mathematician.

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History of measurement

The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC.

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IEEE Std 260.1-2004

IEEE Standard IEEE Std 260.1-2004 provides standard letter symbols for units of measurement for use in all applications in multiple contexts.

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In mathematics, an integral assigns numbers to functions in a way that can describe displacement, area, volume, and other concepts that arise by combining infinitesimal data.

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International Committee for Weights and Measures

The International Committee for Weights and Measures (abbreviated CIPM from the French Comité international des poids et mesures) consists of eighteen persons, each of a different nationality, from Member States of the Metre Convention (Convention du Mètre) appointed by the General Conference on Weights and Measures (CGPM) whose principal task is to promote worldwide uniformity in units of measurement by taking direct action or by submitting proposals to the CGPM.

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International Electrical Congress

The International Electrical Congress was a series of international meetings, from 1881 - 1904, in the then new field of applied electricity.

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James Clerk Maxwell

James Clerk Maxwell (13 June 1831 – 5 November 1879) was a Scottish scientist in the field of mathematical physics.

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Johann Christian Poggendorff

Johann Christian Poggendorff (29 December 1796 – 24 January 1877), was a German physicist born in Hamburg.

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Josiah Latimer Clark

Josiah Latimer Clark FRAS (10 March 1822 – 30 October 1898), was an English electrical engineer, born in Great Marlow, Buckinghamshire.

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The joule (symbol: J) is a derived unit of energy in the International System of Units.

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Joule heating

Joule heating, also known as Ohmic heating and resistive heating, is the process by which the passage of an electric current through a conductor produces heat.

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The kilogram or kilogramme (symbol: kg) is the base unit of mass in the International System of Units (SI), and is defined as being equal to the mass of the International Prototype of the Kilogram (IPK, also known as "Le Grand K" or "Big K"), a cylinder of platinum-iridium alloy stored by the International Bureau of Weights and Measures at Saint-Cloud, France.

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Letter and digit code

The letter and digit code for resistance and capacitance values and tolerances, which is also known as RKM code or "R notation", is a notation to specify resistor and capacitor values defined in the international standard IEC 60062 (formerly IEC 62) since 1952.

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Letterlike Symbols

Letterlike Symbols is a Unicode block containing 80 characters which are constructed mainly from the glyphs of one or more letters.

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Linearity is the property of a mathematical relationship or function which means that it can be graphically represented as a straight line.

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The metre (British spelling and BIPM spelling) or meter (American spelling) (from the French unit mètre, from the Greek noun μέτρον, "measure") is the base unit of length in some metric systems, including the International System of Units (SI).

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Metrology is the science of measurement.

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Multiplicative inverse

In mathematics, a multiplicative inverse or reciprocal for a number x, denoted by 1/x or x−1, is a number which when multiplied by x yields the multiplicative identity, 1.

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Ohm's law

Ohm's law states that the current through a conductor between two points is directly proportional to the voltage across the two points.

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Omega (capital: Ω, lowercase: ω; Greek ὦ, later ὦ μέγα, Modern Greek ωμέγα) is the 24th and last letter of the Greek alphabet.

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Orders of magnitude (resistance)

No description.

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Philosophical Magazine

The Philosophical Magazine is one of the oldest scientific journals published in English.

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Power (physics)

In physics, power is the rate of doing work, the amount of energy transferred per unit time.

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Quantum Hall effect

The quantum Hall effect (or integer quantum Hall effect) is a quantum-mechanical version of the Hall effect, observed in two-dimensional electron systems subjected to low temperatures and strong magnetic fields, in which the Hall conductance undergoes quantum Hall transitions to take on the quantized values where is the channel current, is the Hall voltage, is the elementary charge and is Planck's constant.

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A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element.

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The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.

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SI base unit

The International System of Units (SI) defines seven units of measure as a basic set from which all other SI units can be derived.

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SI derived unit

SI derived units are units of measurement derived from the seven base units specified by the International System of Units (SI).

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Siemens (unit)

The siemens (symbol: S) is the derived unit of electric conductance, electric susceptance and electric admittance in the International System of Units (SI).

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Siemens mercury unit

The Siemens mercury unit is an obsolete unit of electrical resistance.

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The statohm is the unit of electrical resistance in the electrostatic system of units which was part of the CGS system of units based upon the centimetre, gram and second.

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Symbol (typeface)

Symbol is one of the four standard fonts available on all PostScript-based printers, starting with Apple's original LaserWriter (1985).

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The Electrician

The Electrician, published in London from 1861 to 1952, was the earliest and foremost electrical engineering periodical and scientific journal.

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A thermistor is a type of resistor whose resistance is dependent on temperature, more so than in standard resistors.

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Unicode is a computing industry standard for the consistent encoding, representation, and handling of text expressed in most of the world's writing systems.

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The volt (symbol: V) is the derived unit for electric potential, electric potential difference (voltage), and electromotive force.

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Voltage, electric potential difference, electric pressure or electric tension (formally denoted or, but more often simply as V or U, for instance in the context of Ohm's or Kirchhoff's circuit laws) is the difference in electric potential between two points.

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The watt (symbol: W) is a unit of power.

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Werner von Siemens

Ernst Werner Siemens (von Siemens from 1888;; 13 December 1816 – 6 December 1892) was a German inventor and industrialist.

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William Henry Preece

Sir William Henry Preece KCB FRS (15 February 1834 – 6 November 1913) was a Welsh electrical engineer and inventor.

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William Thomson, 1st Baron Kelvin

William Thomson, 1st Baron Kelvin, (26 June 1824 – 17 December 1907) was a Scots-Irish mathematical physicist and engineer who was born in Belfast in 1824.

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Gigaohm, Gohm, International ohm, Kilohm, Kiloohm, , Megaohm, Megaohms, Megohm, Milli-ohm, Milliohm, Ohm (unit), Ohm unit, Teraohm, Teraohms, ΚΩ, , .


[1] https://en.wikipedia.org/wiki/Ohm

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