{"id":3038,"date":"2017-05-30T02:54:05","date_gmt":"2017-05-30T02:54:05","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=3038"},"modified":"2024-09-03T17:00:35","modified_gmt":"2024-09-03T17:00:35","slug":"resolucao-comentada-das-questoes-de-fisica-da-ufam-am-017","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/universidades-2017\/ufam-2017\/resolucao-comentada-das-questoes-de-fisica-da-ufam-am-017\/","title":{"rendered":"Resolu\u00e7\u00e3o comentada das quest\u00f5es de F\u00cdSICA da UFAM-AM-017"},"content":{"rendered":"

Resolu\u00e7\u00e3o comentada das quest\u00f5es de F\u00cdSICA da <\/b><\/span><\/span><\/span><\/p>\n

UFAM-AM-017<\/b><\/span><\/span><\/span><\/p>\n

01- <\/b><\/span><\/span><\/span>d =<\/b><\/span><\/span><\/span> 6 km <\/b><\/span><\/span><\/span>= 6.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span> cm \"\"<\/b><\/span><\/span><\/span> <\/b>n\u00famero de passos \"\"<\/b><\/span><\/span><\/span> \"\" = 0,075.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span> = 7,5.10<\/b><\/span><\/span><\/span>-2<\/b><\/span><\/span><\/sup><\/span>.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span> = <\/b><\/span><\/span><\/span>7,5.10<\/b><\/span><\/span><\/span>3<\/b><\/span><\/span><\/sup><\/span> \"\"<\/b><\/span><\/span><\/span> na <\/b><\/span><\/span><\/span>ordem de grandeza 7,5 \u00e9 arredondado para 10 \"\"<\/b><\/span><\/span><\/span> <\/b>OG <\/b><\/span><\/span><\/span>= 10.10<\/b><\/span><\/span><\/span>3<\/b><\/span><\/span><\/sup><\/span> <\/b>= 10<\/b><\/span><\/span><\/span>4<\/b><\/span><\/span><\/sup><\/span><\/p>\n

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

02- <\/b><\/span><\/span><\/span>A <\/b><\/span><\/span><\/span>mesma velocidade do bal\u00e3<\/b><\/span><\/span><\/span>o, vertical e para cima de <\/b><\/span><\/span><\/span>valor V<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span> = 6 m\/s estando a uma altura h<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span> = 78,2 m <\/b><\/span><\/span><\/span>e sujeito \u00e0 <\/b><\/span><\/span><\/span>acelera\u00e7\u00e3o da gravidade g = 10 m\/s<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span>.<\/b><\/span><\/span><\/span><\/p>\n

Trata-se de um <\/b><\/span><\/span><\/span>lan\u00e7amento vertical para cima<\/b><\/span><\/span><\/span> e, ap\u00f3s a <\/b><\/span><\/span><\/span>subida ele retorna ao solo, onde h = 0.<\/b><\/span><\/span><\/span><\/p>\n

S = S<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span> + V<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span>t + \"\"<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span><\/span>h = h<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span> + V<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span>t + \"\"<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span><\/span>0 = 78,2 + 6t – \"\"<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span><\/span>5t<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span> <\/b>\u2013 6t \u2013 78,2 = 0.<\/b><\/span><\/span><\/span><\/p>\n

\u2206 <\/span>= 36 + 4.5.78,2 <\/b><\/span><\/span><\/span>= 1600 \"\"<\/b><\/span><\/span><\/span> \"\"<\/b><\/span><\/span><\/span> = 40<\/b><\/span><\/span><\/span>.<\/b><\/span><\/span><\/span><\/p>\n

t= + 6 \"\"<\/b><\/span><\/span><\/span>40\/2.5 \"\"<\/b><\/span><\/span><\/span> <\/b>t<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> negativo <\/b><\/span><\/span><\/span>e <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> = \"\" <\/b><\/span><\/span><\/span>= 4,6 s.<\/b><\/span><\/span><\/span><\/p>\n

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

03-<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

04- <\/b><\/span><\/span><\/span>S\u00e3o dados:<\/b><\/span><\/span><\/span><\/p>\n

S\u00f3lido \"\"<\/b><\/span><\/span><\/span> <\/b>m<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span> = <\/b><\/span><\/span><\/span>300 g, <\/b><\/span><\/span><\/span>c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> ?, <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>os<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 100 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C e <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 60 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C. <\/b><\/span><\/span><\/span><\/p>\n

Calor\u00edmetro<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span><\/span>C<\/b><\/span><\/span><\/span>c<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 20 cal\/<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C, <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>oc<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 30 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C e <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> = <\/b><\/span><\/span><\/span>60 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C.<\/b><\/span><\/span><\/span><\/p>\n

\u00c1gua<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/span>a<\/b><\/span><\/span><\/sub><\/span> = <\/b><\/span><\/span><\/span>200 g, <\/b><\/span><\/span><\/span>c<\/b><\/span><\/span><\/span>a<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 1 cal\/g<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C, <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>oa<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 30 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C e <\/b><\/span><\/span><\/span>t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> =<\/b><\/span><\/span><\/span> 60 <\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C<\/b><\/span><\/span><\/span><\/p>\n

A <\/b><\/span><\/span><\/span>soma das quantidades de calor <\/b><\/span><\/span><\/span>trocadas entre os corpos <\/b><\/span><\/span><\/span>deve ser nula:<\/b><\/span><\/span><\/span><\/p>\n

m<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span>.c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span>.(t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> \u2013 t<\/b><\/span><\/span><\/span>os<\/b><\/span><\/span><\/sub><\/span>) + C<\/b><\/span><\/span><\/span>c<\/b><\/span><\/span><\/sub><\/span>.(t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> \u2013 t<\/b><\/span><\/span><\/span>oc<\/b><\/span><\/span><\/sub><\/span>) + m<\/b><\/span><\/span><\/span>a<\/b><\/span><\/span><\/sub><\/span>.c<\/b><\/span><\/span><\/span>a<\/b><\/span><\/span><\/sub><\/span>.(t<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/sub><\/span> \u2013 t<\/b><\/span><\/span><\/span>oa<\/b><\/span><\/span><\/sub><\/span>) = 0 \"\" <\/b><\/span><\/span><\/span>300.c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span>.(60 \u2013 100) + 20.(60 \u2013 30) + 200.1.(60 \u2013 30) = 0 \"\"<\/b><\/span><\/span><\/span> <\/b>– 12000c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span> + 600 + 6000 = <\/b><\/span><\/span><\/span>0 \"\" <\/b><\/span><\/span><\/span>c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span> = \"\"<\/b><\/span><\/span><\/span> \"\" c<\/b><\/span><\/span><\/span>s<\/b><\/span><\/span><\/sub><\/span> = 0,55 cal\/g<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C.<\/b><\/span><\/span><\/span><\/p>\n

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

05- <\/b><\/span><\/span><\/span><\/p>\n

Ondas circulares em meio bi e tridimensionais<\/b><\/span><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Pontos <\/b><\/span><\/span><\/span>onde se <\/b><\/span><\/span><\/span>encontram uma crista e um vale (interfer\u00eancia destrutiva) <\/b><\/span><\/span><\/span>s\u00e3o chamados de <\/b><\/span><\/span><\/span>n\u00f3s (linhas nodais).<\/b><\/span><\/span><\/span><\/p>\n

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

06- <\/b><\/span><\/span><\/span>A <\/b><\/span><\/span><\/span>imagem do beija-flor \u00e9 sim\u00e9trica ao objeto <\/b><\/span><\/span><\/span>em rela\u00e7\u00e3o ao espelho <\/b><\/span><\/span><\/span>(dist\u00e2ncia objeto-espelho = dist\u00e2ncia imagem-espelho) <\/b><\/span><\/span><\/span>e assim, a <\/b><\/span><\/span><\/span>dist\u00e2ncia pedida <\/b><\/span><\/span><\/span>(<\/b><\/span><\/span><\/span>dist\u00e2ncia entre a c\u00e2mera e a posi\u00e7\u00e3o<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

aparente da imagem <\/b><\/span><\/span><\/span>do beija-flor) vale <\/b><\/span><\/span><\/span>d =<\/b><\/span><\/span><\/span> (3m + 2m) <\/b><\/span><\/span><\/span>= 5,00 m.<\/b><\/span><\/span><\/span><\/p>\n

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

07- <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

O <\/b><\/span><\/span><\/span>trabalho entre A e C n\u00e3o depende da trajet\u00f3ria <\/b><\/span><\/span><\/span>(as linhas verticais s\u00e3o superf\u00edcies equipotenciais) mas, <\/b><\/span><\/span><\/span>W<\/b><\/span><\/span><\/span>AC<\/b><\/span><\/span><\/sub><\/span> = q.U = q.E.d<\/b><\/span><\/span><\/span> = 0,1.10<\/b><\/span><\/span><\/span>-6<\/b><\/span><\/span><\/sup><\/span>.5.10<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span>.10.10<\/b><\/span><\/span><\/span>-2<\/b><\/span><\/span><\/sup><\/span> <\/b>= 5.10<\/b><\/span><\/span><\/span>-5<\/b><\/span><\/span><\/sup><\/span> j.<\/b><\/span><\/span><\/span><\/p>\n

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

08- <\/b><\/span><\/span><\/span>Anotando os pontos que est\u00e3o em curto-circuito <\/b><\/span><\/span><\/span>e <\/b><\/span><\/span><\/span>refazendo o circuito:<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Observe na <\/b><\/span><\/span><\/span>\u00faltima figura <\/b><\/span><\/span><\/span>que os <\/b><\/span><\/span><\/span>tr\u00eas resistores de 30 \u03a9 <\/b><\/span><\/span><\/span>est\u00e3o associados em <\/b><\/span><\/span><\/span>paralelo<\/b><\/span><\/span><\/span> e a <\/b><\/span><\/span><\/span>resist\u00eancia equivalente entre A e D vale R<\/b><\/span><\/span><\/span>eq<\/b><\/span><\/span><\/sub><\/span> = \"\"<\/b><\/span><\/span><\/span> = 10 <\/b><\/span><\/span><\/span>\u03a9.<\/b><\/span><\/span><\/span><\/p>\n

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

 <\/p>\n

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

Resolu\u00e7\u00e3o comentada das quest\u00f5es de F\u00cdSICA da UFAM-AM-017 01- d = 6 km = 6.105 cm n\u00famero de passos = 0,075.105 = 7,5.10-2.105 = 7,5.103 na ordem de grandeza 7,5 \u00e9 arredondado para 10 OG = 10.103 = 104 R- C 02- A mesma velocidade do bal\u00e3o, vertical e para cima de valor Vo = 6 m\/s estando a uma<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":3036,"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-3038","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/3038","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=3038"}],"version-history":[{"count":1,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/3038\/revisions"}],"predecessor-version":[{"id":3039,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/3038\/revisions\/3039"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/3036"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=3038"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}