{"id":655,"date":"2015-04-12T15:24:24","date_gmt":"2015-04-12T15:24:24","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=655"},"modified":"2024-09-02T16:54:31","modified_gmt":"2024-09-02T16:54:31","slug":"resolucao-comentada-da-uemg-2015","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/universidades-2015\/exercicios-da-uemg-2015\/resolucao-comentada-da-uemg-2015\/","title":{"rendered":"Resolu\u00e7\u00e3o comentada da UEMG 2015"},"content":{"rendered":"

RESOLU\u00c7\u00d5ES<\/b><\/span><\/span><\/span><\/p>\n

01- <\/span><\/span><\/span>P = W\/\u2206t<\/b><\/span><\/span><\/span>— <\/b><\/span><\/span>l\u00e2mpada<\/b><\/span><\/span><\/span> — 60 = W<\/b><\/span><\/span>l<\/b><\/span><\/span><\/sub>\/3600 — <\/b><\/span><\/span>W<\/b><\/span><\/span><\/span>l<\/b><\/span><\/span><\/sub><\/span> = 216 000 J<\/b><\/span><\/span><\/span><\/p>\n

P = W\/\u2206t<\/b><\/span><\/span><\/span>— <\/b><\/span><\/span>televis\u00e3o<\/b><\/span><\/span><\/span> — 90 = W<\/b><\/span><\/span>t<\/b><\/span><\/span><\/sub>\/3600 — <\/b><\/span><\/span>W<\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/sub><\/span> = 324 000 J<\/b><\/span><\/span><\/span><\/p>\n

A <\/b><\/span><\/span><\/span>televis\u00e3o<\/b><\/span><\/span><\/span> consome <\/b><\/span><\/span><\/span>mais energia el\u00e9trica,<\/b><\/span><\/span><\/span> mas a <\/b><\/span><\/span><\/span>tens\u00e3o <\/b><\/span><\/span><\/span>em cada aparelho <\/b><\/span><\/span><\/span>\u00e9 a mesma<\/b><\/span><\/span><\/span>, pois est\u00e3o <\/b><\/span><\/span><\/span>associados em paralelo<\/b><\/span><\/span><\/span>.<\/b><\/span><\/span><\/span><\/p>\n

R- D<\/b><\/span><\/span><\/span><\/p>\n

02- <\/span><\/span><\/span>Sendo o peso <\/b><\/span><\/span>P = mg e a massa do objeto a mesma<\/b><\/span><\/span><\/span>, o <\/b><\/span><\/span>peso diminuiria<\/b><\/span><\/span><\/span> se a <\/b><\/span><\/span>acelera\u00e7\u00e3o da gravidadeg diminu\u00edsse<\/b><\/span><\/span><\/span>, sendo g fornecida por <\/b><\/span><\/span>g = GM\/r<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span> onde:<\/b><\/span><\/span><\/p>\n

g\u00a0<\/b><\/span><\/span><\/span> —valor da acelera\u00e7\u00e3o da gravidade \u00e0 uma dist\u00e2ncia r do centro do planeta (m\/s<\/b><\/span><\/span>2<\/b><\/span><\/span><\/sup>\u00a0ou N\/kg)<\/b><\/span><\/span><\/p>\n

G\u00a0<\/b><\/span><\/span><\/span> —\u00a0constante de gravita\u00e7\u00e3o universal (6,67.10<\/b><\/span><\/span>-11<\/b><\/span><\/span><\/sup>\u00a0Nm<\/b><\/span><\/span>2<\/b><\/span><\/span><\/sup>\/kg<\/b><\/span><\/span>2<\/b><\/span><\/span><\/sup>)<\/b><\/span><\/span><\/p>\n

M\u00a0 <\/b><\/span><\/span><\/span>—\u00a0massa do planeta (kg)<\/b><\/span><\/span><\/p>\n

r\u00a0<\/b><\/span><\/span><\/span> —dist\u00e2ncia do centro do planeta ao centro do corpo (m)<\/b><\/span><\/span><\/p>\n

Observe na express\u00e3o <\/b><\/span><\/span>g = GM\/r<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span> que, para que <\/b><\/span><\/span>g <\/b><\/span><\/span><\/span>e consequentemente o <\/b><\/span><\/span>peso diminua<\/b><\/span><\/span><\/span>, voc\u00ea deve <\/b><\/span><\/span>aumentar o raio r da Terra<\/b><\/span><\/span><\/span> (inversamente proporcional a r<\/b><\/span><\/span>2<\/b><\/span><\/span><\/sup>) e<\/b><\/span><\/span>diminuir a massa M da Terra<\/b><\/span><\/span><\/span> (diretamente proporcional a M).<\/b><\/span><\/span><\/p>\n

R – C<\/b><\/span><\/span><\/span><\/p>\n

03-<\/span><\/span><\/span> Veja figura abaixo:<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

R- C<\/b><\/span><\/span><\/span><\/p>\n

04- <\/span><\/span><\/span>I. Falsa<\/b><\/span><\/span><\/span>— a velocidade da <\/b><\/span><\/span><\/span>luz no ar<\/b><\/span><\/span><\/span> \u00e9 de aproximadamente <\/b><\/span><\/span><\/span>3.10<\/b><\/span><\/span><\/span>8<\/b><\/span><\/span><\/sup><\/span> m\/s e do som 340 m\/s.<\/b><\/span><\/span><\/span><\/p>\n

II. Correta<\/b><\/span><\/span><\/span>— quanto <\/b><\/span><\/span><\/span>mais denso<\/b><\/span><\/span><\/span> o meio, <\/b><\/span><\/span><\/span>maior a velocidade do som e menor a da luz.<\/b><\/span><\/span><\/span><\/p>\n

III.Falsa<\/b><\/span><\/span><\/span>— o <\/b><\/span><\/span><\/span>som aud\u00edvel humano<\/b><\/span><\/span><\/span> tem frequ\u00eancia entre <\/b><\/span><\/span><\/span>20 Hz e 20000 Hz<\/b><\/span><\/span><\/span> e a da luz vis\u00edvel <\/b><\/span><\/span><\/span>entre 10<\/b><\/span><\/span><\/span>15<\/b><\/span><\/span><\/sup><\/span> Hz e 10<\/b><\/span><\/span><\/span>16<\/b><\/span><\/span><\/sup><\/span> Hz.<\/b><\/span><\/span><\/span><\/p>\n

IV. Falsa<\/b><\/span><\/span><\/span>— <\/b><\/span><\/span><\/span>ambas <\/b><\/span><\/span><\/span>apresentam <\/b><\/span><\/span><\/span>natureza ondulat\u00f3ria.<\/b><\/span><\/span><\/span><\/p>\n

R- C<\/b><\/span><\/span><\/span><\/p>\n

05- <\/span><\/span><\/span>Coment\u00e1io 1. Falso <\/b><\/span><\/span><\/span>— todas as part\u00edculas (mat\u00e9ria) possuem massa.<\/b><\/span><\/span><\/span><\/p>\n

Coment\u00e1rios 2 e 3.<\/b><\/span><\/span><\/span> <\/b>Corretos.<\/b><\/span><\/span><\/span><\/p>\n

R- A<\/b><\/span><\/span><\/span><\/p>\n

06- <\/span><\/span><\/span>Espelhos <\/b><\/span><\/span><\/span>esf\u00e9ricos convexos<\/b><\/span><\/span><\/span> fornecem imagem <\/b><\/span><\/span><\/span>virtual, direita e menor que o objeto<\/b><\/span><\/span><\/span>, que permitem ter um maior campo visual e espelhos <\/b><\/span><\/span><\/span>esf\u00e9ricos c\u00f4ncavos,<\/b><\/span><\/span><\/span>com o objeto entre o foco e o espelho, fornecem imagem <\/b><\/span><\/span><\/span>virtual, direita e maior que o objeto,<\/b><\/span><\/span><\/span> fazendo com que possuam maior riqueza de detalhes.<\/b><\/span><\/span><\/span><\/p>\n

R- D<\/b><\/span><\/span><\/span><\/p>\n

 <\/p>\n

Voltar para os Exerc\u00edcios<\/span><\/a><\/h3>\n","protected":false},"excerpt":{"rendered":"

RESOLU\u00c7\u00d5ES 01- P = W\/\u2206t— l\u00e2mpada — 60 = Wl\/3600 — Wl = 216 000 J P = W\/\u2206t— televis\u00e3o — 90 = Wt\/3600 — Wt = 324 000 J A televis\u00e3o consome mais energia el\u00e9trica, mas a tens\u00e3o em cada aparelho \u00e9 a mesma, pois est\u00e3o associados em paralelo. R- D 02- Sendo o peso P = mg e<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":653,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-655","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/655","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/comments?post=655"}],"version-history":[{"count":2,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/655\/revisions"}],"predecessor-version":[{"id":657,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/655\/revisions\/657"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/653"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=655"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}