{"id":319,"date":"2023-07-06T20:08:20","date_gmt":"2023-07-06T23:08:20","guid":{"rendered":"https:\/\/xequematenem.com.br\/blog\/?p=319"},"modified":"2024-06-11T14:26:46","modified_gmt":"2024-06-11T17:26:46","slug":"questao-148-enem-2022","status":"publish","type":"post","link":"https:\/\/xequematenem.com.br\/blog\/questao-148-enem-2022\/","title":{"rendered":"Quest\u00e3o 148 &#8211; ENEM 2022"},"content":{"rendered":"\n<p class=\"has-text-align-center wp-block-paragraph\">Quest\u00e3o 148 &#8211; Raz\u00e3o e propor\u00e7\u00e3o<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A luminosidade L de uma estrela est\u00e1 relacionada com o <strong>raio R e com a temperatura T<\/strong> dessa estrela segundo a Lei de Stefan-Boltzmann:&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>L = c . R<sup>2<\/sup> . T<sup>4<\/sup> <\/strong>em que c \u00e9 uma constante igual para todas as estrelas.<\/p>\n\n\n\n<p class=\"has-small-font-size wp-block-paragraph\">Dispon\u00edvel em: http:\/\/ciencia.hsw.uol.com.br. Acesso em: 22 nov. 2013 (adaptado)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Considere duas <strong>estrelas E e F, sendo que a estrela E tem metade do raio da estrela F e o dobro da temperatura de F<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Indique por L<sub>E<\/sub>&nbsp; e L<sub>F<\/sub> suas respectivas luminosidades.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A rela\u00e7\u00e3o entre as luminosidades dessas duas estrelas \u00e9 dada por<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A) L<sub>E<\/sub> = L<sub>F<\/sub>\/2<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B) L<sub>E<\/sub> = L<sub>F<\/sub>\/4<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C) L<sub>E<\/sub> = L<sub>F<\/sub><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">D) L<sub>E<\/sub> = 4L<sub>F<\/sub>\u00a0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">E) L<sub>E<\/sub> = 8L<sub>F<\/sub>\u00a0<\/p>\n\n\n\n<ol class=\"wp-block-list\"><\/ol>\n\n\n\n<p class=\"has-text-align-center has-large-font-size wp-block-paragraph\"><strong>Solu\u00e7\u00e3o<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">O enunciado diz que sendo raio R<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">R<sub>E<\/sub> = R<sub>F<\/sub>\/2&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">E temperatura T<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">T<sub>E<\/sub> = 2T<sub>F<\/sub>&nbsp;&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">De acordo com a f\u00f3rmula dada temos que<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L<sub>F<\/sub> = c . (R<sub>F<\/sub>)<sup>2<\/sup> . (T<sub>F<\/sub>)<sup>4<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">e<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L<sub>E<\/sub> = c . (R<sub>E<\/sub>)<sup>2<\/sup> . (T<sub>E<\/sub>)<sup>4<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Usando as duas primeiras igualdades temos que<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L<sub>E<\/sub> = c . (R<sub>F<\/sub>\/2)<sup>2<\/sup> . (2T<sub>F<\/sub>)<sup>4<\/sup><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">=&gt; L<sub>E<\/sub> = c . (R<sub>F<\/sub>)<sup>2<\/sup>\/4 . 16(T<sub>F<\/sub>)<sup>4<\/sup>&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Dividindo 16 por 4 temos<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L<sub>E<\/sub> = 4. c . (R<sub>F<\/sub>)<sup>2<\/sup> . (T<sub>F<\/sub>)<sup>4<\/sup>&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ou seja<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L<sub>E<\/sub> = 4L<sub>F<\/sub><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Alternativa D<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Veja a resolu\u00e7\u00e3o com mais detalhes no v\u00eddeo abaixo!<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe title=\"\ud83d\udd18Quest\u00e3o 148 - Caderno Azul | Raz\u00e3o e Propor\u00e7\u00e3o | MATEM\u00c1TICA ENEM 2022\" width=\"800\" height=\"450\" data-src=\"https:\/\/www.youtube.com\/embed\/bCV4t2SGs_k?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" class=\"lazyload\" data-load-mode=\"1\"><\/iframe>\n<\/div><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Quest\u00e3o 148 &#8211; Raz\u00e3o e propor\u00e7\u00e3o A luminosidade L de uma estrela est\u00e1 relacionada com o raio R e com a temperatura T dessa estrela segundo a Lei de Stefan-Boltzmann:&nbsp; L = c . R2 . T4 em que c \u00e9 uma constante igual para todas as estrelas. Dispon\u00edvel em: http:\/\/ciencia.hsw.uol.com.br. Acesso em: 22 nov. [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,4],"tags":[],"area-do-conhecimento":[132,118],"assunto":[35],"class_list":["post-319","post","type-post","status-publish","format-standard","hentry","category-questoes-do-enem","category-4","area-do-conhecimento-matematica","area-do-conhecimento-matematica-e-suas-tecnologias","assunto-razao-e-proporcao"],"_links":{"self":[{"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/posts\/319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/comments?post=319"}],"version-history":[{"count":1,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/posts\/319\/revisions"}],"predecessor-version":[{"id":6509,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/posts\/319\/revisions\/6509"}],"wp:attachment":[{"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/media?parent=319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/categories?post=319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/tags?post=319"},{"taxonomy":"area-do-conhecimento","embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/area-do-conhecimento?post=319"},{"taxonomy":"assunto","embeddable":true,"href":"https:\/\/xequematenem.com.br\/blog\/wp-json\/wp\/v2\/assunto?post=319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}