CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available" lang="ca" dir="ltr"> <head> <meta charset="UTF-8"> <title>Fenomen del regel - Viquipèdia, l'enciclopèdia lliure</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-sticky-header-enabled vector-toc-available";var cookie=document.cookie.match(/(?:^|; )cawikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":[",\t.",".\t,"],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy","wgMonthNames":["","gener","febrer","març","abril","maig","juny","juliol","agost","setembre","octubre","novembre","desembre"],"wgRequestId":"62f2f997-64b3-45bd-aa56-329c32c4b7ab","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Fenomen_del_regel","wgTitle":"Fenomen del regel","wgCurRevisionId":34553807,"wgRevisionId":34553807,"wgArticleId":953378,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["Control d'autoritats","Termodinàmica"],"wgPageViewLanguage":"ca","wgPageContentLanguage":"ca","wgPageContentModel":"wikitext","wgRelevantPageName":"Fenomen_del_regel","wgRelevantArticleId":953378,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":true,"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"ca","pageLanguageDir":"ltr","pageVariantFallbacks":"ca"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":true,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":4000,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q909865","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false}; RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","wikibase.client.data-bridge.externalModifiers":"ready"};RLPAGEMODULES=["ext.cite.ux-enhancements","mediawiki.page.media","site","mediawiki.page.ready","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.UkensKonkurranse","ext.gadget.refToolbar","ext.gadget.charinsert","ext.gadget.AltresViccionari","ext.gadget.purgetab","ext.gadget.DocTabs","ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","wikibase.client.data-bridge.init","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession","oojs-ui.styles.icons-media","oojs-ui-core.icons"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=ca&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediamessages.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.data-bridge.externalModifiers%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=ca&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=ca&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.19"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/4/45/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="1097"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/4/45/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="731"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="585"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Fenomen del regel - Viquipèdia, l'enciclopèdia lliure"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//ca.m.wikipedia.org/wiki/Fenomen_del_regel"> <link rel="alternate" type="application/x-wiki" title="Modifica" href="/w/index.php?title=Fenomen_del_regel&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Viquipèdia (ca)"> <link rel="EditURI" type="application/rsd+xml" href="//ca.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://ca.wikipedia.org/wiki/Fenomen_del_regel"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.ca"> <link rel="alternate" type="application/atom+xml" title="Canal de sindicació Atom Viquipèdia" href="/w/index.php?title=Especial:Canvis_recents&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Fenomen_del_regel rootpage-Fenomen_del_regel skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Vés al contingut</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Lloc"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" title="Menú principal" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Menú principal" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Menú principal</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Menú principal</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">mou a la barra lateral</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">amaga</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navegació </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Portada" title="Visiteu la pàgina principal [z]" accesskey="z"><span>Portada</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Especial:Article_aleatori" title="Carrega una pàgina a l’atzar [x]" accesskey="x"><span>Article a l'atzar</span></a></li><li id="n-Articles-de-qualitat" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Articles_de_qualitat"><span>Articles de qualitat</span></a></li><li id="n-specialpages" class="mw-list-item"><a href="/wiki/Especial:P%C3%A0gines_especials"><span>Pàgines especials</span></a></li> </ul> </div> </div> <div id="p-Comunitat" class="vector-menu mw-portlet mw-portlet-Comunitat" > <div class="vector-menu-heading"> Comunitat </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-portal" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Portal" title="Sobre el projecte, què podeu fer, on trobareu les coses"><span>Portal viquipedista</span></a></li><li id="n-Agenda-d'actes" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Trobades"><span>Agenda d'actes</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Especial:Canvis_recents" title="Una llista dels canvis recents al wiki [r]" accesskey="r"><span>Canvis recents</span></a></li><li id="n-La-taverna" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:La_taverna"><span>La taverna</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Contacte"><span>Contacte</span></a></li><li id="n-Xat" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Canals_IRC"><span>Xat</span></a></li><li id="n-help" class="mw-list-item"><a href="/wiki/Viquip%C3%A8dia:Ajuda" title="El lloc per a saber més coses"><span>Ajuda</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Portada" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Viquipèdia" src="/static/images/mobile/copyright/wikipedia-wordmark-ca.svg" style="width: 7.5em; height: 1.4375em;"> <img class="mw-logo-tagline" alt="l'Enciclopèdia Lliure" src="/static/images/mobile/copyright/wikipedia-tagline-ca.svg" width="120" height="14" style="width: 7.5em; height: 0.875em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Especial:Cerca" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Cerca a la Viquipèdia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Cerca</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Cerca a Viquipèdia" aria-label="Cerca a Viquipèdia" autocapitalize="sentences" title="Cerca a la Viquipèdia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Especial:Cerca"> </div> <button class="cdx-button cdx-search-input__end-button">Cerca</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Eines personals"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Aparença"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Aparença" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Aparença</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=ca.wikipedia.org&uselang=ca" class=""><span>Donatius</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Especial:Crea_compte&returnto=Fenomen+del+regel" title="Us animem a crear un compte i iniciar una sessió, encara que no és obligatori" class=""><span>Crea un compte</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Especial:Registre_i_entrada&returnto=Fenomen+del+regel" title="Us animem a registrar-vos, però no és obligatori [o]" accesskey="o" class=""><span>Inicia la sessió</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Més opcions" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Eines personals" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Eines personals</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="Menú d'usuari" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/?wmf_source=donate&wmf_medium=sidebar&wmf_campaign=ca.wikipedia.org&uselang=ca"><span>Donatius</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Especial:Crea_compte&returnto=Fenomen+del+regel" title="Us animem a crear un compte i iniciar una sessió, encara que no és obligatori"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Crea un compte</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Especial:Registre_i_entrada&returnto=Fenomen+del+regel" title="Us animem a registrar-vos, però no és obligatori [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Inicia la sessió</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pàgines per a editors no registrats <a href="/wiki/Ajuda:Introducci%C3%B3" aria-label="Vegeu més informació sobre l'edició"><span>més informació</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Especial:Contribucions_pr%C3%B2pies" title="Una llista de les modificacions fetes des d'aquesta adreça IP [y]" accesskey="y"><span>Contribucions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Especial:Discussi%C3%B3_personal" title="Discussió sobre les edicions per aquesta adreça ip. [n]" accesskey="n"><span>Discussió per aquest IP</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Lloc"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contingut" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contingut</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">mou a la barra lateral</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">amaga</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">Inici</div> </a> </li> <li id="toc-Fusió_de_superfície" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Fusió_de_superfície"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Fusió de superfície</span> </div> </a> <ul id="toc-Fusió_de_superfície-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Exemples_de_regelació" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Exemples_de_regelació"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Exemples de regelació</span> </div> </a> <ul id="toc-Exemples_de_regelació-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Referències" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Referències"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Referències</span> </div> </a> <ul id="toc-Referències-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contingut" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" title="Taula de continguts" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Commuta la taula de continguts." > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Commuta la taula de continguts.</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Fenomen del regel</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Vés a un article en una altra llengua. Disponible en 15 llengües" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-15" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">15 llengües</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Regelace" title="Regelace - txec" lang="cs" hreflang="cs" data-title="Regelace" data-language-autonym="Čeština" data-language-local-name="txec" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Regelation" title="Regelation - alemany" lang="de" hreflang="de" data-title="Regelation" data-language-autonym="Deutsch" data-language-local-name="alemany" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Regelation" title="Regelation - anglès" lang="en" hreflang="en" data-title="Regelation" data-language-autonym="English" data-language-local-name="anglès" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Regelaci%C3%B3n" title="Regelación - espanyol" lang="es" hreflang="es" data-title="Regelación" data-language-autonym="Español" data-language-local-name="espanyol" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Ricongelamento" title="Ricongelamento - italià" lang="it" hreflang="it" data-title="Ricongelamento" data-language-autonym="Italiano" data-language-local-name="italià" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E5%BE%A9%E6%B0%B7" title="復氷 - japonès" lang="ja" hreflang="ja" data-title="復氷" data-language-autonym="日本語" data-language-local-name="japonès" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Regelasjon" title="Regelasjon - noruec nynorsk" lang="nn" hreflang="nn" data-title="Regelasjon" data-language-autonym="Norsk nynorsk" data-language-local-name="noruec nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Regelasjon" title="Regelasjon - noruec bokmål" lang="nb" hreflang="nb" data-title="Regelasjon" data-language-autonym="Norsk bokmål" data-language-local-name="noruec bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Regelacja" title="Regelacja - polonès" lang="pl" hreflang="pl" data-title="Regelacja" data-language-autonym="Polski" data-language-local-name="polonès" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Regelo" title="Regelo - portuguès" lang="pt" hreflang="pt" data-title="Regelo" data-language-autonym="Português" data-language-local-name="portuguès" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Regelacija" title="Regelacija - eslovè" lang="sl" hreflang="sl" data-title="Regelacija" data-language-autonym="Slovenščina" data-language-local-name="eslovè" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Regelation" title="Regelation - suec" lang="sv" hreflang="sv" data-title="Regelation" data-language-autonym="Svenska" data-language-local-name="suec" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%89%E0%AE%B0%E0%AF%81%E0%AE%95%E0%AE%BF%E0%AE%AF%E0%AF%81%E0%AE%B1%E0%AF%88%E0%AE%A4%E0%AE%B2%E0%AF%8D" title="உருகியுறைதல் - tàmil" lang="ta" hreflang="ta" data-title="உருகியுறைதல்" data-language-autonym="தமிழ்" data-language-local-name="tàmil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Hi%E1%BB%87n_t%C6%B0%E1%BB%A3ng_t%C3%A1i_%C4%91%C3%B3ng_b%C4%83ng" title="Hiện tượng tái đóng băng - vietnamita" lang="vi" hreflang="vi" data-title="Hiện tượng tái đóng băng" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamita" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%BE%A9%E5%86%B0%E7%8F%BE%E8%B1%A1" title="復冰現象 - xinès" lang="zh" hreflang="zh" data-title="復冰現象" data-language-autonym="中文" data-language-local-name="xinès" class="interlanguage-link-target"><span>中文</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q909865#sitelinks-wikipedia" title="Modifica enllaços interlingües" class="wbc-editpage">Modifica els enllaços</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Espais de noms"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Fenomen_del_regel" title="Vegeu el contingut de la pàgina [c]" accesskey="c"><span>Pàgina</span></a></li><li id="ca-talk" class="new vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Discussi%C3%B3:Fenomen_del_regel&action=edit&redlink=1" rel="discussion" class="new" title="Discussió sobre el contingut d'aquesta pàgina (encara no existeix) [t]" accesskey="t"><span>Discussió</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Canvia la variant de llengua" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">català</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Vistes"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Fenomen_del_regel"><span>Mostra</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&action=edit" title="Modifica el codi font d'aquesta pàgina [e]" accesskey="e"><span>Modifica</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&action=history" title="Versions antigues d'aquesta pàgina [h]" accesskey="h"><span>Mostra l'historial</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Eines de la pàgina"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Eines" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Eines</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Eines</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">mou a la barra lateral</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">amaga</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="Més opcions" > <div class="vector-menu-heading"> Accions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Fenomen_del_regel"><span>Mostra</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&action=edit" title="Modifica el codi font d'aquesta pàgina [e]" accesskey="e"><span>Modifica</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&action=history"><span>Mostra l'historial</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Especial:Enlla%C3%A7os/Fenomen_del_regel" title="Una llista de totes les pàgines wiki que enllacen amb aquesta [j]" accesskey="j"><span>Què hi enllaça</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Especial:Seguiment/Fenomen_del_regel" rel="nofollow" title="Canvis recents a pàgines enllaçades des d'aquesta pàgina [k]" accesskey="k"><span>Canvis relacionats</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&oldid=34553807" title="Enllaç permanent a aquesta revisió de la pàgina"><span>Enllaç permanent</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&action=info" title="Més informació sobre aquesta pàgina"><span>Informació de la pàgina</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Especial:Citau&page=Fenomen_del_regel&id=34553807&wpFormIdentifier=titleform" title="Informació sobre com citar aquesta pàgina"><span>Citau aquest article</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Especial:UrlShortener&url=https%3A%2F%2Fca.wikipedia.org%2Fwiki%2FFenomen_del_regel"><span>Obtén una URL abreujada</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Especial:QrCode&url=https%3A%2F%2Fca.wikipedia.org%2Fwiki%2FFenomen_del_regel"><span>Descarrega el codi QR</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Imprimeix/exporta </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-create_a_book" class="mw-list-item"><a href="/w/index.php?title=Especial:Llibre&bookcmd=book_creator&referer=Fenomen+del+regel"><span>Crea un llibre</span></a></li><li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Especial:DownloadAsPdf&page=Fenomen_del_regel&action=show-download-screen"><span>Baixa com a PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Fenomen_del_regel&printable=yes" title="Versió per a impressió d'aquesta pàgina [p]" accesskey="p"><span>Versió per a impressora</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> En altres projectes </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q909865" title="Enllaç a l'element del repositori de dades connectat [g]" accesskey="g"><span>Element a Wikidata</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Eines de la pàgina"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Aparença"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Aparença</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">mou a la barra lateral</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">amaga</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">De la Viquipèdia, l'enciclopèdia lliure</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="ca" dir="ltr"><figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fitxer:Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_(1917).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/45/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg/220px-Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg" decoding="async" width="220" height="201" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/45/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg/330px-Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/45/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg/440px-Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg 2x" data-file-width="464" data-file-height="424" /></a><figcaption>Experiment clàssic que implica la regelació d'un bloc de gel a mesura que hi passa un cable tensat.</figcaption></figure> <p>El <b>fenomen del regel</b> (en anglès: <i>Regelation</i>) és el fenomen de fondre sota pressió i congelació una altra vegada quan es redueix la pressió.<sup id="cite_ref-gec_1-0" class="reference"><a href="#cite_note-gec-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Es pot demostrar amb un filferro lligat a un bloc de <a href="/wiki/Gel" class="mw-redirect" title="Gel">gel</a> que estigui sotmès a pressió.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>El fenomen funciona millor amb materials de molta conductivitat tèrmica com el <a href="/wiki/Coure" title="Coure">coure</a>.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>Si es fa servir un filferro d'1 mm de diàmetre sobre un bloc de gel de 50 mm d'amplada, la superfície on s'exerceix la força és 50 mm². Això és 50 x 10<sup>-6</sup> m².<br />La força (en <a href="/wiki/Newton_(unitat)" title="Newton (unitat)">newtons</a>) és igual a la pressió (en <a href="/wiki/Pascal_(unitat)" title="Pascal (unitat)">pascals</a>) multiplicada per la superfície (en m²). <br />Si, com a mínim, 500 atm (50 MPa) calen per a fondre el gel, una força de (50×10⁶ Pa)(50×10<sup>-6</sup> m²) = 2500 N necessita una força aproximadament igual al pes de 250 <a href="/wiki/Kilogram" class="mw-redirect" title="Kilogram">kg</a> sobre la Terra. </p><p>El fenomen del regel va ser descobert per <a href="/wiki/Michael_Faraday" title="Michael Faraday">Michael Faraday</a>. El regel ocorre només en substàncies com el gel, el qual té la propietat d'expandir-se en congelar-se. El <a href="/wiki/Punt_de_fusi%C3%B3" title="Punt de fusió">punt de fusió</a> del gel baixa per cada 0,0072 °C atm addicional de pressió que s'hi aplica. Per exemple, es necessita una pressió de 500 <a href="/wiki/Atmosfera_(unitat)" title="Atmosfera (unitat)">atmosferes</a> per a fondre el gel a –4 °C.<sup id="cite_ref-ams_4-0" class="reference"><a href="#cite_note-ams-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Fusió_de_superfície"><span id="Fusi.C3.B3_de_superf.C3.ADcie"></span>Fusió de superfície</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Fenomen_del_regel&action=edit&section=1" title="Modifica la secció: Fusió de superfície"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/w/index.php?title=Fitxer:Melting_curve_of_water-ca.svg&lang=ca" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/05/Melting_curve_of_water-ca.svg/langca-220px-Melting_curve_of_water-ca.svg.png" decoding="async" width="220" height="124" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/05/Melting_curve_of_water-ca.svg/langca-330px-Melting_curve_of_water-ca.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/05/Melting_curve_of_water-ca.svg/langca-440px-Melting_curve_of_water-ca.svg.png 2x" data-file-width="605" data-file-height="340" /></a><figcaption>Corba de fusió de l'aigua</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/Fitxer:Surface_of_ice_Ih.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Surface_of_ice_Ih.jpg/220px-Surface_of_ice_Ih.jpg" decoding="async" width="220" height="127" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Surface_of_ice_Ih.jpg/330px-Surface_of_ice_Ih.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/9d/Surface_of_ice_Ih.jpg/440px-Surface_of_ice_Ih.jpg 2x" data-file-width="657" data-file-height="380" /></a><figcaption>Estructura molecular del gel prop de la superfície</figcaption></figure><p>Per a un gel normal <a href="/wiki/Cristall" title="Cristall">cristal·lí</a> lluny per sota del seu punt de fusió hi haurà alguna relaxació dels àtoms prop de la superfície i hi ha una significativa fusió en les capes de la superfície més que no pas una relaxació simètrica de les posicions dels àtoms. La <a href="/wiki/Resson%C3%A0ncia_magn%C3%A8tica_nuclear" title="Ressonància magnètica nuclear">ressonància magnètica nuclear</a> proporciona evidència d'una capa líquida en la superfície del gel que ha estat mesurada en 12 <a href="/w/index.php?title=1_E-9_m&action=edit&redlink=1" class="new" title="1 E-9 m (encara no existeix)">nm</a> a –24 °C i 70 nm a –0,7 °C. La fusió de la superfície comença ja a –33 °C.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>La fusió de superfície es pot donar pels factors següents: </p> <ul><li>Baix <a href="/wiki/Coeficient_de_fricci%C3%B3" title="Coeficient de fricció">coeficient de fricció</a> del gel, com experimenten els patinadors.</li> <li>Facilitat de <a href="/w/index.php?title=Compactaci%C3%B3_de_materials&action=edit&redlink=1" class="new" title="Compactació de materials (encara no existeix)">compactació</a> del gel.</li> <li>Alta <a href="/wiki/Adhesi%C3%B3" title="Adhesió">adhesió</a> de les superfícies de gel.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Exemples_de_regelació"><span id="Exemples_de_regelaci.C3.B3"></span>Exemples de regelació</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Fenomen_del_regel&action=edit&section=2" title="Modifica la secció: Exemples de regelació"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Una <a href="/wiki/Glacera" title="Glacera">glacera</a> pot exercir prou quantitat de pressió en la seva superfície inferior per a abaixar el punt de fusió del seu gel. La fusió del gel de la base de la glacera permet que aquesta es mogui des d'un punt més alt a un punt més baix. L'aigua líquida pot fluir des de la base d'una glacera a altituds baixes quan la temperatura de l'aire està per sobre del punt de congelació de l'aigua.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Referències"><span id="Refer.C3.A8ncies"></span>Referències</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Fenomen_del_regel&action=edit&section=3" title="Modifica la secció: Referències"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="reflist" style="list-style-type: decimal;"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-gec-1"><span class="mw-cite-backlink"><a href="#cite_ref-gec_1-0">↑</a></span> <span class="reference-text"><span class="citation" style="font-style:normal">«<a rel="nofollow" class="external text" href="http://www.enciclopedia.cat/gran-enciclopedia-catalana/0206700.xml">Fenomen del regel</a>». <i><a href="/wiki/Gran_Enciclop%C3%A8dia_Catalana" title="Gran Enciclopèdia Catalana">Gran Enciclopèdia Catalana</a></i>.  Barcelona:  <a href="/wiki/Grup_Enciclop%C3%A8dia_Catalana" class="mw-redirect" title="Grup Enciclopèdia Catalana">Grup Enciclopèdia Catalana</a>.</span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text"><span class="citation" style="font-style:normal">«<a rel="nofollow" class="external text" href="http://rspa.royalsocietypublishing.org/content/332/1588/51.full.pdf+html">Proc Roy Soc paper 1973</a>».</span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a></span> <span class="reference-text"><span class="citation" style="font-style:normal">«<a rel="nofollow" class="external text" href="https://web.archive.org/web/20120426072323/http://www.td.mw.tum.de/tum-td/de/forschung/pub/CD_Grigull/047.pdf">Some esperiments</a>». Arxivat de l'<a rel="nofollow" class="external text" href="https://www.td.mw.tum.de/tum-td/de/forschung/pub/CD_Grigull/047.pdf">original</a> el 2012-04-26. [Consulta: 29 desembre 2011].</span></span> </li> <li id="cite_note-ams-4"><span class="mw-cite-backlink"><a href="#cite_ref-ams_4-0">↑</a></span> <span class="reference-text"><span class="citation" style="font-style:normal">«<a rel="nofollow" class="external text" href="https://web.archive.org/web/20060225000000/https://web.archive.org/web/20060225201328/http://amsglossary.allenpress.com/glossary/search?id=regelation1">Glossary of Meteorology: Regelation</a>». Arxivat de l'<a rel="nofollow" class="external text" href="http://amsglossary.allenpress.com/glossary/search?id=regelation1">original</a> el 2006-02-25. [Consulta: 29 desembre 2011].</span>, American Meteorological Society, 2000</span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a></span> <span class="reference-text">Physics Today, December 2005, pp.50-55</span> </li> </ol></div></div> <div role="navigation" class="navbox" aria-labelledby="Estats_de_la_matèria" style="padding:3px"><table class="nowraplinks collapsible collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><div class="plainlinks hlist navbar mini"><ul><li class="nv-view"><span typeof="mw:File"><a href="/wiki/Plantilla:Estats_de_la_mat%C3%A8ria" title="Plantilla:Estats de la matèria"><img alt="Vegeu aquesta plantilla" src="//upload.wikimedia.org/wikipedia/commons/thumb/2/28/Commons-emblem-notice.svg/18px-Commons-emblem-notice.svg.png" decoding="async" width="18" height="18" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/28/Commons-emblem-notice.svg/27px-Commons-emblem-notice.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/28/Commons-emblem-notice.svg/36px-Commons-emblem-notice.svg.png 2x" data-file-width="48" data-file-height="48" /></a></span></li></ul></div><div id="Estats_de_la_matèria" style="font-size:114%;margin:0 4em"><a href="/wiki/Estat_de_la_mat%C3%A8ria" title="Estat de la matèria">Estats de la matèria</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0px;background:transparent;color:inherit;"><div style="padding:0px;"><table class="navbox-columns-table" style="border-spacing: 0px; text-align:left;width:100%;"><tbody><tr><td class="navbox-abovebelow" colspan="1" style="font-weight:bold;width:20%;"><a href="/wiki/S%C3%B2lid" title="Sòlid">Sòlid</a></td><td class="navbox-abovebelow" colspan="1" style="border-left:2px solid #fdfdfd;font-weight:bold;width:20%;"><a href="/wiki/L%C3%ADquid" title="Líquid">Líquid</a></td><td class="navbox-abovebelow" colspan="1" style="border-left:2px solid #fdfdfd;font-weight:bold;width:20%;"><a href="/wiki/Gas" title="Gas">Gas</a> / <a href="/wiki/Vapor" title="Vapor">Vapor</a></td><td class="navbox-abovebelow" colspan="1" style="border-left:2px solid #fdfdfd;font-weight:bold;width:20%;"><a href="/wiki/Plasma_(estat_de_la_mat%C3%A8ria)" title="Plasma (estat de la matèria)">Plasma</a></td></tr></tbody></table></div></td><td class="navbox-image" rowspan="7" style="width:1px;padding:0px 0px 0px 2px"><div><span typeof="mw:File"><a href="/wiki/Fitxer:Phase_change_-_ca.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Phase_change_-_ca.svg/200px-Phase_change_-_ca.svg.png" decoding="async" width="200" height="198" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Phase_change_-_ca.svg/300px-Phase_change_-_ca.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Phase_change_-_ca.svg/400px-Phase_change_-_ca.svg.png 2x" data-file-width="429" data-file-height="425" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Baixa energia</th><td class="navbox-list navbox-even" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Condensat_de_Bose-Einstein" title="Condensat de Bose-Einstein">Condensat de Bose-Einstein</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Condensat_fermi%C3%B2nic" title="Condensat fermiònic">Condensat fermiònic</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Efecte_Hall_qu%C3%A0ntum" class="mw-redirect" title="Efecte Hall quàntum">Efecte Hall quàntum</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Mat%C3%A8ria_de_Rydberg" title="Matèria de Rydberg">Matèria de Rydberg</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Mat%C3%A8ria_estranya" title="Matèria estranya">Matèria estranya</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Superfluid" title="Superfluid">Superfluid</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Supers%C3%B2lid" title="Supersòlid">Supersòlid</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Alta energia</th><td class="navbox-list navbox-odd" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Fluid_supercr%C3%ADtic" title="Fluid supercrític">Fluid supercrític</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Mat%C3%A8ria_degenerada" title="Matèria degenerada">Matèria degenerada</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Mat%C3%A8ria_QCD" title="Matèria QCD">Matèria QCD</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Plasma_de_quarks-gluons" class="mw-redirect" title="Plasma de quarks-gluons">Plasma de quarks-gluons</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Altres estats</th><td class="navbox-list navbox-even" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Col%C2%B7loide" title="Col·loide">Col·loide</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Cristall_l%C3%ADquid" title="Cristall líquid">Cristall líquid</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=L%C3%ADquid_string-net&action=edit&redlink=1" class="new" title="Líquid string-net (encara no existeix)">Líquid <i>string-net</i></a> <span style="font-weight:bold;"> ·</span>  Ordenat magnèticament (<a href="/wiki/Antiferromagnetisme" title="Antiferromagnetisme">antiferromagnètic</a>, <a href="/wiki/Ferrimagnetisme" title="Ferrimagnetisme">ferrimagnètic</a>, <a href="/wiki/Ferromagnetisme" title="Ferromagnetisme">ferromagnètic</a>)<span style="font-weight:bold;"> ·</span>  <a href="/wiki/Supervidre" title="Supervidre">Supervidre</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Vidre" title="Vidre">Vidre</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Canvi_d%27estat" title="Canvi d'estat">Canvis d'estat</a></th><td class="navbox-list navbox-odd" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Cristal%C2%B7litzaci%C3%B3" title="Cristal·lització">Cristal·lització</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Ebullici%C3%B3" title="Ebullició">Ebullició</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Evaporaci%C3%B3" title="Evaporació">Evaporació</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Evaporaci%C3%B3_flash" title="Evaporació flash">Evaporació flash</a> <span style="font-weight:bold;"> ·</span>  <a class="mw-selflink selflink">Fenomen del regel</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=Fluid_saturat&action=edit&redlink=1" class="new" title="Fluid saturat (encara no existeix)">Fluid saturat</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Fusi%C3%B3_(canvi_d%27estat)" title="Fusió (canvi d'estat)">Fusió</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=L%C3%ADnia_cr%C3%ADtica&action=edit&redlink=1" class="new" title="Línia crítica (encara no existeix)">Línia crítica</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Solidificaci%C3%B3" title="Solidificació">Solidificació</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Subfusi%C3%B3" title="Subfusió">Subfusió</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Sublimaci%C3%B3" title="Sublimació">Sublimació</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Sublimaci%C3%B3_inversa" title="Sublimació inversa">Sublimació inversa</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Punt_cr%C3%ADtic" title="Punt crític">Punt crític</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Punt_d%27ebullici%C3%B3" title="Punt d'ebullició">Punt d'ebullició</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Punt_de_fusi%C3%B3" title="Punt de fusió">Punt de fusió</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Punt_lambda" title="Punt lambda">Punt lambda</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Punt_triple" title="Punt triple">Punt triple</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Quantitats</th><td class="navbox-list navbox-even" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Calor_latent" title="Calor latent">Calor latent</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Constant_de_Trouton" class="mw-redirect" title="Constant de Trouton">Constant de Trouton</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=Energia_interna_latent&action=edit&redlink=1" class="new" title="Energia interna latent (encara no existeix)">Energia interna latent</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Entalpia_de_fusi%C3%B3" class="mw-redirect" title="Entalpia de fusió">Entalpia de fusió</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Entalpia_de_sublimaci%C3%B3" title="Entalpia de sublimació">Entalpia de sublimació</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Entalpia_de_vaporitzaci%C3%B3" class="mw-redirect" title="Entalpia de vaporització">Entalpia de vaporització</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Relaci%C3%B3_de_Trouton" title="Relació de Trouton">Relació de Trouton</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Volatilitat" title="Volatilitat">Volatilitat</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Conceptes</th><td class="navbox-list navbox-odd" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"><a href="/wiki/Binodal" title="Binodal">Binodal</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Corba_de_refredament" title="Corba de refredament">Corba de refredament</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=Cuspidal&action=edit&redlink=1" class="new" title="Cuspidal (encara no existeix)">Cuspidal</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Fluid_comprimit" title="Fluid comprimit">Fluid comprimit</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Efecte_Leidenfrost" title="Efecte Leidenfrost">Efecte Leidenfrost</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Efecte_Mpemba" title="Efecte Mpemba">Efecte Mpemba</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Efecte_termo-diel%C3%A8ctric" title="Efecte termo-dielèctric">Efecte termo-dielèctric</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Equaci%C3%B3_d%27estat" title="Equació d'estat">Equació d'estat</a> <span style="font-weight:bold;"> ·</span>  <a href="/w/index.php?title=Ordre_i_desordre&action=edit&redlink=1" class="new" title="Ordre i desordre (encara no existeix)">Ordre i desordre</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Superconductivitat" title="Superconductivitat">Superconductivitat</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Superescalfament" class="mw-redirect" title="Superescalfament">Superescalfament</a> <span style="font-weight:bold;"> ·</span>  <a href="/wiki/Aigua_sobreescalfada" title="Aigua sobreescalfada">Vapor reescalfat</a></div></td></tr></tbody></table></div> <div role="navigation" class="navbox" aria-labelledby="Bases_d&#039;informació" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th id="Bases_d&#039;informació" scope="row" class="navbox-group" style="width:1%">Bases d'informació</th><td class="navbox-list navbox-odd" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em"> <ul><li><a href="/wiki/GEC" class="mw-redirect" title="GEC">GEC</a> (<a rel="nofollow" class="external text" href="https://www.enciclopedia.cat/gran-enciclopedia-catalana/regel">1</a>)</li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Obtingut de «<a dir="ltr" href="https://ca.wikipedia.org/w/index.php?title=Fenomen_del_regel&oldid=34553807">https://ca.wikipedia.org/w/index.php?title=Fenomen_del_regel&oldid=34553807</a>»</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Especial:Categorias" title="Especial:Categorias">Categoria</a>: <ul><li><a href="/wiki/Categoria:Termodin%C3%A0mica" title="Categoria:Termodinàmica">Termodinàmica</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Categoria oculta: <ul><li><a href="/wiki/Categoria:Control_d%27autoritats" title="Categoria:Control d'autoritats">Control d'autoritats</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> La pàgina va ser modificada per darrera vegada el 31 gen 2025 a les 21:07.</li> <li id="footer-info-copyright">El text està disponible sota la <a href="/wiki/Viquip%C3%A8dia:Text_de_la_llic%C3%A8ncia_de_Creative_Commons_Reconeixement-Compartir_Igual_4.0_No_adaptada" title="Viquipèdia:Text de la llicència de Creative Commons Reconeixement-Compartir Igual 4.0 No adaptada"> Llicència de Creative Commons Reconeixement i Compartir-Igual</a>; es poden aplicar termes addicionals. Vegeu les <a class="external text" href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use/ca">Condicions d'ús</a>. Wikipedia® (Viquipèdia™) és una <a href="/wiki/Marca_comercial" title="Marca comercial">marca registrada</a> de <a rel="nofollow" class="external text" href="https://www.wikimediafoundation.org">Wikimedia Foundation, Inc</a>.<br /></li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Política de privadesa</a></li> <li id="footer-places-about"><a href="/wiki/Viquip%C3%A8dia:Quant_a_la_Viquip%C3%A8dia">Quant al projecte Viquipèdia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Viquip%C3%A8dia:Av%C3%ADs_d%27exempci%C3%B3_de_responsabilitat">Descàrrec de responsabilitat</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Codi de conducta</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Desenvolupadors</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/ca.wikipedia.org">Estadístiques</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Declaració de cookies</a></li> <li id="footer-places-mobileview"><a href="//ca.m.wikipedia.org/w/index.php?title=Fenomen_del_regel&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Versió per a mòbils</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/static/images/footer/wikimedia-button.svg" width="84" height="29"><img src="/static/images/footer/wikimedia.svg" width="25" height="25" alt="Wikimedia Foundation" lang="en" loading="lazy"></picture></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><picture><source media="(min-width: 500px)" srcset="/w/resources/assets/poweredby_mediawiki.svg" width="88" height="31"><img src="/w/resources/assets/mediawiki_compact.svg" alt="Powered by MediaWiki" lang="en" width="25" height="25" loading="lazy"></picture></a></li> </ul> </footer> </div> </div> </div> <div class="vector-header-container vector-sticky-header-container"> <div id="vector-sticky-header" class="vector-sticky-header"> <div class="vector-sticky-header-start"> <div class="vector-sticky-header-icon-start vector-button-flush-left vector-button-flush-right" aria-hidden="true"> <button class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-sticky-header-search-toggle" tabindex="-1" data-event-name="ui.vector-sticky-search-form.icon"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Cerca</span> </button> </div> <div role="search" class="vector-search-box-vue vector-search-box-show-thumbnail vector-search-box"> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail"> <form action="/w/index.php" id="vector-sticky-search-form" class="cdx-search-input cdx-search-input--has-end-button"> <div class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Cerca a Viquipèdia"> <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Especial:Cerca"> </div> <button class="cdx-button cdx-search-input__end-button">Cerca</button> </form> </div> </div> </div> <div class="vector-sticky-header-context-bar"> <nav aria-label="Contingut" class="vector-toc-landmark"> <div id="vector-sticky-header-toc" class="vector-dropdown mw-portlet mw-portlet-sticky-header-toc vector-sticky-header-toc vector-button-flush-left" > <input type="checkbox" id="vector-sticky-header-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-sticky-header-toc" class="vector-dropdown-checkbox " aria-label="Commuta la taula de continguts." > <label id="vector-sticky-header-toc-label" for="vector-sticky-header-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Commuta la taula de continguts.</span> </label> <div class="vector-dropdown-content"> <div id="vector-sticky-header-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div class="vector-sticky-header-context-bar-primary" aria-hidden="true" ><span class="mw-page-title-main">Fenomen del regel</span></div> </div> </div> <div class="vector-sticky-header-end" aria-hidden="true"> <div class="vector-sticky-header-icons"> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-talk-sticky-header" tabindex="-1" data-event-name="talk-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbles mw-ui-icon-wikimedia-speechBubbles"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-subject-sticky-header" tabindex="-1" data-event-name="subject-sticky-header"><span class="vector-icon mw-ui-icon-article mw-ui-icon-wikimedia-article"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-history-sticky-header" tabindex="-1" data-event-name="history-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-history mw-ui-icon-wikimedia-wikimedia-history"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only mw-watchlink" id="ca-watchstar-sticky-header" tabindex="-1" data-event-name="watch-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-star mw-ui-icon-wikimedia-wikimedia-star"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-edit-sticky-header" tabindex="-1" data-event-name="wikitext-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-wikiText mw-ui-icon-wikimedia-wikimedia-wikiText"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-ve-edit-sticky-header" tabindex="-1" data-event-name="ve-edit-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-edit mw-ui-icon-wikimedia-wikimedia-edit"></span> <span></span> </a> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only" id="ca-viewsource-sticky-header" tabindex="-1" data-event-name="ve-edit-protected-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-editLock mw-ui-icon-wikimedia-wikimedia-editLock"></span> <span></span> </a> </div> <div class="vector-sticky-header-buttons"> <button class="cdx-button cdx-button--weight-quiet mw-interlanguage-selector" id="p-lang-btn-sticky-header" tabindex="-1" data-event-name="ui.dropdown-p-lang-btn-sticky-header"><span class="vector-icon mw-ui-icon-wikimedia-language mw-ui-icon-wikimedia-wikimedia-language"></span> <span>15 llengües</span> </button> <a href="#" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive" id="ca-addsection-sticky-header" tabindex="-1" data-event-name="addsection-sticky-header"><span class="vector-icon mw-ui-icon-speechBubbleAdd-progressive mw-ui-icon-wikimedia-speechBubbleAdd-progressive"></span> <span>Afegeix un tema</span> </a> </div> <div class="vector-sticky-header-icon-end"> <div class="vector-user-links"> </div> </div> </div> </div> </div> <div class="mw-portlet mw-portlet-dock-bottom emptyPortlet" id="p-dock-bottom"> <ul> </ul> </div> <script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-657b46f875-xbpw8","wgBackendResponseTime":114,"wgPageParseReport":{"limitreport":{"cputime":"0.102","walltime":"0.248","ppvisitednodes":{"value":1135,"limit":1000000},"postexpandincludesize":{"value":35682,"limit":2097152},"templateargumentsize":{"value":6371,"limit":2097152},"expansiondepth":{"value":10,"limit":100},"expensivefunctioncount":{"value":0,"limit":500},"unstrip-depth":{"value":0,"limit":20},"unstrip-size":{"value":2986,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 78.845 1 -total"," 45.46% 35.843 1 Plantilla:Referències"," 28.46% 22.441 1 Plantilla:Autoritat"," 25.88% 20.405 1 Plantilla:Estats_de_la_matèria"," 24.03% 18.943 1 Plantilla:Navbox_with_columns"," 23.99% 18.918 1 Plantilla:GEC"," 19.44% 15.328 4 Plantilla:Ref-web"," 19.13% 15.086 1 Plantilla:Navbox"," 10.11% 7.972 2 Plantilla:Data_consulta"," 1.86% 1.470 48 Plantilla:·"]},"scribunto":{"limitreport-timeusage":{"value":"0.021","limit":"10.000"},"limitreport-memusage":{"value":1190985,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-7f76cf74bc-977f5","timestamp":"20250307110718","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Fenomen del regel","url":"https:\/\/ca.wikipedia.org\/wiki\/Fenomen_del_regel","sameAs":"http:\/\/www.wikidata.org\/entity\/Q909865","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q909865","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2011-12-29T19:03:22Z","dateModified":"2025-01-31T20:07:15Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/4\/45\/Regelation_Image_from_page_256_of_%22The_Ontario_high_school_physics%22_%281917%29.jpg"}</script> </body> </html>