{"id":47280,"date":"2019-11-03T21:15:50","date_gmt":"2019-11-03T20:15:50","guid":{"rendered":"https:\/\/www.thermal-engineering.org\/o-que-e-absorptividade-absorptancia-definicao\/"},"modified":"2020-01-23T08:38:48","modified_gmt":"2020-01-23T07:38:48","slug":"o-que-e-absorptividade-absorptancia-definicao","status":"publish","type":"post","link":"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/","title":{"rendered":"O que \u00e9 Absorptividade &#8211; Absorpt\u00e2ncia &#8211; Defini\u00e7\u00e3o"},"content":{"rendered":"<div class=\"su-quote su-quote-style-default\">\n<div class=\"su-quote-inner su-clearfix\">Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de absor\u00e7\u00e3o, \u03b1, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o incidente em uma superf\u00edcie que \u00e9 absorvida pela superf\u00edcie.\u00a0Engenharia T\u00e9rmica<\/div>\n<\/div>\n<div class=\"su-divider su-divider-style-dotted\"><\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-spacer\"><\/div>\n<h2>Absor\u00e7\u00e3o &#8211; Absor\u00e7\u00e3o<\/h2>\n<p><a href=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/emissivity-of-various-material-table.png\"><img loading=\"lazy\" class=\"alignright size-medium wp-image-20969 lazy-loaded\" src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/emissivity-of-various-material-table-226x300.png\" alt=\"emissividade de v\u00e1rios materiais\" width=\"226\" height=\"300\" data-lazy-type=\"image\" data-src=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/emissivity-of-various-material-table-226x300.png\" \/><\/a>Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de\u00a0<strong>absor\u00e7\u00e3o<\/strong>\u00a0,\u00a0<strong>\u03b1<\/strong>\u00a0, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o incidente em uma superf\u00edcie que \u00e9 absorvida pela superf\u00edcie.\u00a0Como a emissividade, o valor da absortividade est\u00e1 na faixa de 0 &lt;\u03b1 &lt;1.<\/p>\n<p>A partir de sua defini\u00e7\u00e3o, um\u00a0<strong>corpo negro<\/strong>\u00a0, que \u00e9 um corpo f\u00edsico idealizado, absorve toda\u00a0<strong>a radia\u00e7\u00e3o eletromagn\u00e9tica<\/strong>\u00a0incidente\u00a0, independentemente da frequ\u00eancia ou \u00e2ngulo de incid\u00eancia.\u00a0Ou seja, um corpo negro \u00e9 um absorvedor perfeito.\u00a0Como para objetos reais a capacidade de\u00a0<strong>absor\u00e7\u00e3o<\/strong>\u00a0\u00e9 menor que a unidade, um objeto real n\u00e3o pode absorver toda a luz incidente.\u00a0A absor\u00e7\u00e3o incompleta pode ser devida a parte da luz incidente ser transmitida atrav\u00e9s do corpo ou a parte refletida na superf\u00edcie do corpo.<\/p>\n<p>Em geral, a\u00a0<strong>absor\u00e7\u00e3o<\/strong>\u00a0e a\u00a0<a title=\"Emissividade - Emissividade de Materiais\" href=\"https:\/\/www.nuclear-power.com\/nuclear-engineering\/heat-transfer\/radiation-heat-transfer\/emissivity-emissivity-of-materials\/\"><strong>emissividade<\/strong><\/a>\u00a0s\u00e3o interconectadas pela\u00a0<strong>Lei de Kirchhoff da radia\u00e7\u00e3o t\u00e9rmica<\/strong>\u00a0, que afirma:<\/p>\n<p><em>Para um corpo arbitr\u00e1rio que emite e absorve radia\u00e7\u00e3o t\u00e9rmica em equil\u00edbrio termodin\u00e2mico, a emissividade \u00e9 igual \u00e0 absor\u00e7\u00e3o.<\/em><\/p>\n<p><strong>emissividade \u03b5 = absortividade \u03b1<\/strong><\/p>\n<p>Note que a radia\u00e7\u00e3o vis\u00edvel ocupa uma faixa muito estreita do espectro de 0,4 a 0,76 nm, n\u00e3o podemos fazer julgamentos sobre a escurid\u00e3o de uma superf\u00edcie com base em observa\u00e7\u00f5es visuais.\u00a0Por exemplo, considere o papel branco que reflete a luz vis\u00edvel e, portanto, parece branco.\u00a0Por outro lado, \u00e9 essencialmente preto para a radia\u00e7\u00e3o infravermelha (capacidade de\u00a0<strong>absor\u00e7\u00e3o \u03b1 = 0,94<\/strong>\u00a0), pois eles absorvem fortemente a radia\u00e7\u00e3o de comprimento de onda longo.<\/p>\n<\/div>\n<\/div>\n<div class=\"lgc-column lgc-grid-parent lgc-grid-100 lgc-tablet-grid-100 lgc-mobile-grid-100 lgc-equal-heights lgc-first lgc-last\">\n<div class=\"inside-grid-column\">\n<div class=\"su-accordion\">\n<div class=\"su-spoiler su-spoiler-style-default su-spoiler-icon-arrow\" data-anchor=\"References\">\n<div class=\"su-spoiler-content su-clearfix\">\n<p>&nbsp;<\/p>\n<\/div>\n<p>&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;&#8230;.<\/p>\n<p>Este artigo \u00e9 baseado na tradu\u00e7\u00e3o autom\u00e1tica do artigo original em ingl\u00eas. Para mais informa\u00e7\u00f5es, consulte o artigo em ingl\u00eas. Voc\u00ea pode nos ajudar. Se voc\u00ea deseja corrigir a tradu\u00e7\u00e3o, envie-a para: translations@nuclear-power.com ou preencha o formul\u00e1rio de tradu\u00e7\u00e3o on-line. Agradecemos sua ajuda, atualizaremos a tradu\u00e7\u00e3o o mais r\u00e1pido poss\u00edvel. Obrigado.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de absor\u00e7\u00e3o, \u03b1, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o incidente em uma superf\u00edcie que \u00e9 absorvida pela superf\u00edcie.\u00a0Engenharia T\u00e9rmica Absor\u00e7\u00e3o &#8211; Absor\u00e7\u00e3o Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de\u00a0absor\u00e7\u00e3o\u00a0,\u00a0\u03b1\u00a0, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o &#8230; <a title=\"O que \u00e9 Absorptividade &#8211; Absorpt\u00e2ncia &#8211; Defini\u00e7\u00e3o\" class=\"read-more\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/\" aria-label=\"More on O que \u00e9 Absorptividade &#8211; Absorpt\u00e2ncia &#8211; Defini\u00e7\u00e3o\">Ler mais<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[14],"tags":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v15.4 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>O que \u00e9 Absorptividade - Absor\u00e7\u00e3o - Defini\u00e7\u00e3o<\/title>\n<meta name=\"description\" content=\"Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de absor\u00e7\u00e3o, \u03b1, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o incidente em uma superf\u00edcie que \u00e9 absorvida pela superf\u00edcie. Engenharia T\u00e9rmica\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/\" \/>\n<meta property=\"og:locale\" content=\"pt_BR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"O que \u00e9 Absorptividade - Absor\u00e7\u00e3o - Defini\u00e7\u00e3o\" \/>\n<meta property=\"og:description\" content=\"Outra propriedade importante de radia\u00e7\u00e3o de uma superf\u00edcie \u00e9 sua capacidade de absor\u00e7\u00e3o, \u03b1, que \u00e9 a fra\u00e7\u00e3o da energia de radia\u00e7\u00e3o incidente em uma superf\u00edcie que \u00e9 absorvida pela superf\u00edcie. Engenharia T\u00e9rmica\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/\" \/>\n<meta property=\"og:site_name\" content=\"Thermal Engineering\" \/>\n<meta property=\"article:published_time\" content=\"2019-11-03T20:15:50+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2020-01-23T07:38:48+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/emissivity-of-various-material-table-226x300.png\" \/>\n<meta name=\"twitter:card\" content=\"summary\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\">\n\t<meta name=\"twitter:data1\" content=\"Nick Connor\">\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\">\n\t<meta name=\"twitter:data2\" content=\"1 minuto\">\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.thermal-engineering.org\/fr\/#website\",\"url\":\"https:\/\/www.thermal-engineering.org\/fr\/\",\"name\":\"Thermal Engineering\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":\"https:\/\/www.thermal-engineering.org\/fr\/?s={search_term_string}\",\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"pt-BR\"},{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/#primaryimage\",\"inLanguage\":\"pt-BR\",\"url\":\"https:\/\/thermal-engineering.org\/wp-content\/uploads\/2019\/05\/emissivity-of-various-material-table-226x300.png\"},{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/#webpage\",\"url\":\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/\",\"name\":\"O que \\u00e9 Absorptividade - Absor\\u00e7\\u00e3o - Defini\\u00e7\\u00e3o\",\"isPartOf\":{\"@id\":\"https:\/\/www.thermal-engineering.org\/fr\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/#primaryimage\"},\"datePublished\":\"2019-11-03T20:15:50+00:00\",\"dateModified\":\"2020-01-23T07:38:48+00:00\",\"author\":{\"@id\":\"https:\/\/www.thermal-engineering.org\/fr\/#\/schema\/person\/e8c544db9afedaec8574d6464f9398bb\"},\"description\":\"Outra propriedade importante de radia\\u00e7\\u00e3o de uma superf\\u00edcie \\u00e9 sua capacidade de absor\\u00e7\\u00e3o, \\u03b1, que \\u00e9 a fra\\u00e7\\u00e3o da energia de radia\\u00e7\\u00e3o incidente em uma superf\\u00edcie que \\u00e9 absorvida pela superf\\u00edcie. Engenharia T\\u00e9rmica\",\"inLanguage\":\"pt-BR\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.thermal-engineering.org\/pt-br\/o-que-e-absorptividade-absorptancia-definicao\/\"]}]},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.thermal-engineering.org\/fr\/#\/schema\/person\/e8c544db9afedaec8574d6464f9398bb\",\"name\":\"Nick Connor\",\"image\":{\"@type\":\"ImageObject\",\"@id\":\"https:\/\/www.thermal-engineering.org\/fr\/#personlogo\",\"inLanguage\":\"pt-BR\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/84c0dec310b44b65da29dc9df6925239?s=96&d=mm&r=g\",\"caption\":\"Nick Connor\"}}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","_links":{"self":[{"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/posts\/47280"}],"collection":[{"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/comments?post=47280"}],"version-history":[{"count":0,"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/posts\/47280\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/media?parent=47280"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/categories?post=47280"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.thermal-engineering.org\/pt-br\/wp-json\/wp\/v2\/tags?post=47280"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}