SI units

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iec-col "> <section class="block block-layout-builder block-inline-blockmodule-overview-header clearfix iec-overview-block iec-full-width with-margin banner-body-empty" style="background-image:url(/system/files/styles/original_image/private/2019-10/content/media/image/sibg.jpg?itok=mh8Vt18T);"> <div class="iec-overview-block-content"> <div class="container"> <div class="iec-overview-block-text"> <h1 class="text-block-title field--name-field-title condensed">SI units for electricity, magnetism, and light</h1> </div> </div> </div> </section> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2970"> <div class="text-block-header" style="text-align:center;"> <h2 class="text-block-title condensed" style="font-size:34px;" id="article-header-id-2970-electricity-magnetism-and-light"> Electricity, magnetism, and light </h1> </div> <div class="text-block-content" style="text-align:center;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p><a href="http://webstore.iec.ch/webstore/webstore.nsf/ArtNum_PK/39179">IEC 80000-6</a>: this section describes the SI units for electricity and magnetism. This includes: electric current (I), electric charge (Q), electric potential (V), capacitance (C), resistance (R), inductance (L), magnetic flux density (B), active power (P), reactive power (Q), apparent power (S)</p></div> </div> </section> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="dynamic-layout-row iec-row "> <div data-region="r5c1c59445539bc5c1c59445539e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2971"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2971-electric-current-l"> Electric current, l </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ampere, A Usual multiples and sub-multiples: kA, mA, µA</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c59496e323" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2972"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2972-electric-charge-q"> Electric charge, Q </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">coulomb, C; 1 C = 1 A · s<br> For storage batteries, the compound unit A · h is used.</p> <h4 class="first-p">Conversion factors</h4> <p>1 A · h = 3,6 kC</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c594ad2a1e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2973"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2973-electric-potential-v"> Electric potential, V </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">volt, V; 1 V = 1 W/A = 1 kg · m<span style="vertical-align: super; font-size:75%;">2</span>/(s<span style="vertical-align: super; font-size:75%;">3</span> · A)</p> <p>Usual multiples and sub-multiples:<br> kV, mV, µV</p> <p>The unsystematic name "voltage" should be avoided for electric tension or electric potential difference.</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c594bd0513" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2974"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2974-capacitance-c"> Capacitance, C </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">farad, F; 1 F = 1 C/V = 1 s<span style="vertical-align: super; font-size:75%;">4</span> · A<span style="vertical-align: super; font-size:75%;">2</span>/(kg · m<span style="vertical-align: super; font-size:75%;">2</span>)</p> <p>Usual sub-multiples: µF, nF, pF</p> </div> </div> </section> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="dynamic-layout-row iec-row "> <div data-region="r5c1c59445539bc5c1c59445539e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2977"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2977-resistance-r"> Resistance, R </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">ohm, Ω; 1 Ω = 1 V/A = 1 kg · m<span style="vertical-align: super; font-size:75%;">2</span>/(s<span style="vertical-align: super; font-size:75%;">3</span> · A<span style="vertical-align: super; font-size:75%;">2</span>)</p> <p>Usual multiples and sub-multiples:<br> MΩ, kΩ, mΩ</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c59496e323" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2979"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2979-inductance-l"> Inductance, L </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>henry, H; 1 H = 1 V · s/A = 1 kg · m<span style="vertical-align: super; font-size:75%;">2</span>/(s<span style="vertical-align: super; font-size:75%;">2</span> · A<span style="vertical-align: super; font-size:75%;">2</span>)</p> <p>Usual sub-multiples: mH, µH</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c594ad2a1e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2980"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2980-magnetic-flux-density-b"> Magnetic flux density, B </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>tesla, T; 1 T = V · s/m<span style="vertical-align: super; font-size:75%;">2</span> = 1 kg/(s<span style="vertical-align: super; font-size:75%;">2</span> · A)</p> <p>Usual sub-multiples: mT, µT</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c594bd0513" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2981"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2981-active-power-p"> Active power, P </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>watt, W; 1 W = 1 J/s = 1 V · A = 1 kg · m/s<span style="vertical-align: super; font-size:75%;">3</span></p> <p>Usual multiples and sub-multiples: MW, kW, mW</p> </div> </div> </section> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="dynamic-layout-row iec-row "> <div data-region="r5c1c5969093f7c5c1c5969093fa" class="dynamic-layouts-container-column layout-builder--layout__region col-12 iec-col "> <section class="block block-layout-builder block-inline-block-module-white-gray-space clearfix"> <div class="module-white-gray-space-content iec-bg-color iec-bg-white"> </div> </section> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="dynamic-layout-row iec-row "> <div data-region="r5c1c59445539bc5c1c59445539e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2983"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2983-reactive-power-q"> Reactive power, Q </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>volt ampere, V · A; 1 V · A = 1 kg · m/s<span style="vertical-align: super; font-size:75%;">3</span></p> <p>Usual multiples: MV · A, kV · A</p> <p>IEC has adopted the name var, var (volt-ampere reactive power), for the coherent SI unit volt-ampere for reactive power.</p> <h4>Conversion factors</h4> <p>1 var = 1 V · A</p> </div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c59496e323" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2984"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2984-apparent-power-s"> Apparent power, S </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">volt ampere, V · A; 1 V · A = 1 kg · m/s<span style="vertical-align: super; font-size:75%;">3</span></p> <p>Usual multiples: MV · A, kV · A</p></div> </div> </section> </div> <div data-region="r5c1c59445539bc5c1c594ad2a1e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> </div> <div data-region="r5c1c59445539bc5c1c594bd0513" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="iec-full-width iec-bg-grey"> <div class="container"> <div class="dynamic-layout-row iec-row iec-fixed-row-bg "> <div data-region="r5c627bcf91f79c5c627bcf91f7d" class="dynamic-layouts-container-column layout-builder--layout__region col-12 iec-col "> <section class="block block-layout-builder block-inline-block-module-white-gray-space clearfix"> <div class="module-white-gray-space-content iec-bg-color iec-bg-grey"> </div> </section> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2986"> <div class="text-block-header" style="text-align:center;"> <h2 class="text-block-title condensed" style="font-size:34px;" id="article-header-id-2986-light"> Light </h1> </div> <div class="text-block-content" style="text-align:center;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="text-align-center"><a href="http://webstore.iec.ch/webstore/webstore.nsf/ArtNum_PK/42348">ISO 80000-7</a>:  this section describes the SI units for light. This includes: luminous intensity (l), luminous flux (Φ), illuminance (E), light exposure (H)<br>  </p></div> </div> </section> </div> </div> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="iec-full-width iec-bg-grey"> <div class="container"> <div class="dynamic-layout-row iec-row iec-fixed-row-bg "> <div data-region="r5c6299aabbc06c5c6299aabbc0a" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2987"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2987-luminous-intensity-i"> Luminous intensity, I </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">candela, cd</p></div> </div> </section> </div> <div data-region="r5c6299aabbc06c5c6299ca2a100" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2988"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2988-luminous-flux-"> Luminous flux, Φ </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p class="first-p">lumen, lm; 1 lm = 1 cd/sr</p> </div> </div> </section> </div> <div data-region="r5c6299aabbc06c5c6299d2b418e" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2989"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2989-illuminance-e"> Illuminance, E </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>lux, lx; 1 lx = 1 lm/m<span style="vertical-align: super; font-size:75%;">2</span> = 1 cd/(sr · m<span style="vertical-align: super; font-size:75%;">2</span>)</p> </div> </div> </section> </div> <div data-region="r5c6299aabbc06c5c6299d5c3a45" class="dynamic-layouts-container-column layout-builder--layout__region col-3 iec-col "> <section class="block block-iec-section-custom block-layout-builder block-inline-blockmodule-single-element-text clearfix single-element-text" id="single-element-text-2990"> <div class="text-block-header" style="text-align:left;"> <h2 class="text-block-title condensed" style="font-size:24px;" id="article-header-id-2990-light-exposure-h"> Light exposure, H </h1> </div> <div class="text-block-content" style="text-align:left;"> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>lux second, lx · s; 1 lx · s = 1 s · cd/(sr · m<span style="vertical-align: super; font-size:75%;">2</span>)</p> </div> </div> </section> </div> </div> </div> </div> </div> <div class="dynamic-layouts-container custom-12" > <div class="dynamic-layout-row iec-row "> <div data-region="r5c1c5969093f7c5c1c5969093fa" class="dynamic-layouts-container-column layout-builder--layout__region col-12 iec-col "> <section class="block block-block-content block-block-content81d8af24-9afc-48d1-9fb1-b0e5eb08cc6c clearfix"> <div class="field field--name-field-paragraph field--type-entity-reference-revisions 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