{"id":712,"date":"2015-05-12T18:55:40","date_gmt":"2015-05-12T18:55:40","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=712"},"modified":"2024-09-03T13:08:14","modified_gmt":"2024-09-03T13:08:14","slug":"unimontes-2015-exercicios-resolvidos","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/universidades-2015\/unimontes-2015-exercicios-resolvidos\/","title":{"rendered":"UNIMONTES 2015 – Exerc\u00edcios Resolvidos"},"content":{"rendered":"

\"\"<\/p>\n

A\u00a0Universidade Estadual de Montes Claros\u00a0–\u00a0UNIMONTES\u00a0\u00e9 uma institui\u00e7\u00e3o p\u00fablica de ensino superior, sediada em Montes Claros – MG, tendo sob \u00e1rea de influ\u00eancia o Norte e Noroeste de Minas Gerais,\u00a0<\/b><\/span><\/span><\/span>Vale do Mucuri<\/b><\/span><\/span><\/span><\/a>,\u00a0<\/b><\/span><\/span><\/span>Vale do Jequitinhonha<\/b><\/span><\/span><\/span><\/a>, al\u00e9m de parte da Serra Geral, regi\u00e3o Centro-Sul da\u00a0<\/b><\/span><\/span><\/span>Bahia<\/b><\/span><\/span><\/span><\/a>.<\/b><\/span><\/span><\/span><\/p>\n

Localizada na cidade de Montes Claros, centro convergente e polarizador dos demais munic\u00edpios da regi\u00e3o do Norte de Minas Gerais, a\u00a0Unimontes\u00a0\u00e9 uma autarquia de regime especial do Estado de Minas Gerais, na forma do \u00a7 3\u00ba do Art. 82 do Ato das Disposi\u00e7\u00f5es Constitucionais Transit\u00f3rias da Constitui\u00e7\u00e3o do Estado de Minas Gerais, resultante da transforma\u00e7\u00e3o da\u00a0Funda\u00e7\u00e3o Norte-Mineira do Ensino Superior\u00a0-FUNM.<\/b><\/span><\/span><\/span><\/p>\n

A\u00a0Unimontes\u00a0oferece forma\u00e7\u00f5es nas \u00e1reas de sa\u00fade, educa\u00e7\u00e3o, ci\u00eancias sociais aplicadas, ci\u00eancias humanas e ci\u00eancias exatas e tecnol\u00f3gicas, no\u00a0campus-sede de Montes Claros, bem como nos seus\u00a0campi\u00a0de Almenara,\u00a0<\/b><\/span><\/span><\/span>Bras\u00edlia de Minas<\/b><\/span><\/span><\/span><\/a>, Espinosa, Jana\u00faba, Janu\u00e1ria, Paracatu\/Una\u00ed, Pirapora, Salinas e S\u00e3o Francisco e, ainda, no n\u00facleo em Joa\u00edma, al\u00e9m dos mais de 300 munic\u00edpios consorciados.<\/b><\/span><\/span><\/span><\/p>\n

01-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Duas esferas id\u00eanticas,<\/b><\/span><\/span><\/span> <\/b>1 e 2<\/b><\/span><\/span><\/span>, fazem um <\/b><\/span><\/span><\/span>movimento vertical<\/b><\/span><\/span><\/span> em uma regi\u00e3o onde o <\/b><\/span><\/span><\/span>m\u00f3dulo da<\/b><\/span><\/span><\/span> <\/b>acelera\u00e7\u00e3o da gravidade \u00e9<\/b><\/span><\/span><\/span> <\/b>g = 10 m\/s\u00b2<\/b><\/span><\/span><\/span> (veja a figura). <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

No instante<\/b><\/span><\/span><\/span> <\/b>t = 0,<\/b><\/span><\/span><\/span> a <\/b><\/span><\/span><\/span>esfera<\/b><\/span><\/span><\/span> <\/b>1<\/b><\/span><\/span><\/span> <\/b>est\u00e1 em <\/b><\/span><\/span><\/span>repouso e a esfera 2 possui<\/b><\/span><\/span><\/span> <\/b>velocidade inicial de m\u00f3dulo <\/b><\/span><\/span><\/span>v<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span>.<\/b><\/span><\/span><\/span> <\/b>Ambas tocam o solo no mesmo instante.<\/b><\/span><\/span><\/span> O <\/b><\/span><\/span><\/span>valor de <\/b><\/span><\/span><\/span>v<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span>, em m\/s<\/b><\/span><\/span><\/span>, \u00e9<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

02-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

A <\/b><\/span><\/span><\/span>figura <\/b><\/span><\/span><\/span>a seguir mostra o <\/b><\/span><\/span><\/span>projeto de um trecho de uma montanha russa<\/b><\/span><\/span><\/span>. Nessa montanha russa, pretende-se que o <\/b><\/span><\/span><\/span>\u2018loop\u2019 tenha um di\u00e2metro de 6 m de altura.<\/b><\/span><\/span><\/span> O <\/b><\/span><\/span><\/span>carrinho<\/b><\/span><\/span><\/span>, que <\/b><\/span><\/span><\/span>parte do repouso<\/b><\/span><\/span><\/span> no <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

ponto A<\/b><\/span><\/span><\/span>, passa pelo <\/b><\/span><\/span><\/span>ponto B<\/b><\/span><\/span><\/span> na <\/b><\/span><\/span><\/span>imin\u00eancia de perder o contato com o trilho<\/b><\/span><\/span><\/span>. Suponha que <\/b><\/span><\/span><\/span>n\u00e3o exista<\/b><\/span><\/span><\/span> <\/b>atrito<\/b><\/span><\/span><\/span> entre o carrinho e o trilho e que a <\/b><\/span><\/span><\/span>acelera\u00e7\u00e3o da gravidade no local possui m\u00f3dulo <\/b><\/span><\/span><\/span>g= 10 m\/s\u00b2.<\/b><\/span><\/span><\/span> A <\/b><\/span><\/span><\/span>altura H<\/b><\/span><\/span><\/span>, em <\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/span>, \u00e9<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

03-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Dois blocos unidos por um fio<\/b><\/span><\/span><\/span> de massa desprez\u00edvel (veja a figura) s\u00e3o <\/b><\/span><\/span><\/span>liberados a partir do<\/b><\/span><\/span><\/span> <\/b><\/p>\n

\"\"<\/p>\n

repouso.<\/b><\/span><\/span><\/span> As polias s\u00e3o fixas (n\u00e3o giram) e o atrito <\/b><\/span><\/span><\/span>entre elas e a corda \u00e9 tamb\u00e9m desprez\u00edvel.<\/b><\/span><\/span><\/span> O m\u00f3dulo da <\/b><\/span><\/span><\/span>acelera\u00e7\u00e3o da gravidade no local \u00e9 <\/b><\/span><\/span><\/span>g = 10 m\/s<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span>. Sendo <\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 6 kg<\/b><\/span><\/span><\/span> a <\/b><\/span><\/span><\/span>massa do bloco <\/b><\/span><\/span><\/span>1,<\/b><\/span><\/span><\/span> e <\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>= 4 kg<\/b><\/span><\/span><\/span> a <\/b><\/span><\/span><\/span>massa do bloco 2<\/b><\/span><\/span><\/span>, o <\/b><\/span><\/span><\/span>m\u00f3dulo da acelera\u00e7\u00e3o dos blocos<\/b><\/span><\/span><\/span> vale, em <\/b><\/span><\/span><\/span>m\/s<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sup><\/span>,<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

04-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Um <\/b><\/span><\/span><\/span>objeto a <\/b><\/span><\/span><\/span>20 cm<\/b><\/span><\/span><\/span> de dist\u00e2ncia de um espelho tem sua <\/b><\/span><\/span><\/span>imagem<\/b><\/span><\/span><\/span> formada a <\/b><\/span><\/span><\/span>12 cm<\/b><\/span><\/span><\/span> de dist\u00e2ncia do<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

espelho.<\/b><\/span><\/span><\/span><\/p>\n

Se a imagem <\/b><\/span><\/span><\/span>formada \u00e9 <\/b><\/span><\/span><\/span>real<\/b><\/span><\/span><\/span>, o <\/b><\/span><\/span><\/span>tipo <\/b><\/span><\/span><\/span>de espelho e o seu <\/b><\/span><\/span><\/span>foco em cent\u00edmetros<\/b><\/span><\/span><\/span> s\u00e3o<\/b><\/span><\/span><\/span>, respectivamente:<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

05-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Uma <\/b><\/span><\/span><\/span>fonte pontual<\/b><\/span><\/span><\/span> emite <\/b><\/span><\/span><\/span>pulsos peri\u00f3dicos<\/b><\/span><\/span><\/span> enquanto se movimenta <\/b><\/span><\/span><\/span>com velocidade de m\u00f3dulo <\/b><\/span><\/span><\/span>v<\/b><\/span><\/span><\/span>,<\/b><\/span><\/span><\/span> na <\/b><\/span><\/span><\/span>superf\u00edcie de um tanque de \u00e1gua<\/b><\/span><\/span><\/span>, formando um <\/b><\/span><\/span><\/span>padr\u00e3o de ondas<\/b><\/span><\/span><\/span> em que se observa o <\/b><\/span><\/span><\/span>efeito Doppler (veja a figura).<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Pela <\/b><\/span><\/span><\/span>configura\u00e7\u00e3o apresentada na figura<\/b><\/span><\/span><\/span>, podemos <\/b><\/span><\/span><\/span>afirmar corretamente<\/b><\/span><\/span><\/span> que a <\/b><\/span><\/span><\/span>fonte pontual<\/b><\/span><\/span><\/span> se<\/b><\/span><\/span><\/span><\/p>\n

move<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

06-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Uma <\/b><\/span><\/span><\/span>m\u00e1quina t\u00e9rmica<\/b><\/span><\/span><\/span> opera segundo o <\/b><\/span><\/span><\/span>ciclo <\/b><\/span><\/span><\/span>representado no diagrama <\/b><\/span><\/span><\/span>P\u00d7V da figura a seguir<\/b><\/span><\/span><\/span>. O<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

produto P<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span>V<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 12 J<\/b><\/span><\/span><\/span> e a <\/b><\/span><\/span><\/span>efici\u00eancia<\/b><\/span><\/span><\/span> dessa m\u00e1quina \u00e9 de <\/b><\/span><\/span><\/span>40 %<\/b><\/span><\/span><\/span>. O <\/b><\/span><\/span><\/span>trabalho<\/b><\/span><\/span><\/span> realizado por ciclo e o <\/b><\/span><\/span><\/span>calor <\/b><\/span><\/span><\/span>rejeitado por <\/b><\/span><\/span><\/span>essa m\u00e1quina, em <\/b><\/span><\/span><\/span>Joules,<\/b><\/span><\/span><\/span> s\u00e3o, respectivamente:<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

07-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Na <\/b><\/span><\/span><\/span>conta de energia el\u00e9trica<\/b><\/span><\/span><\/span> de uma determinada resid\u00eancia, vieram as <\/b><\/span><\/span><\/span>seguintes informa\u00e7\u00f5es:<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Uma <\/b><\/span><\/span><\/span>geladeira <\/b><\/span><\/span><\/span>dessa resid\u00eancia possui <\/b><\/span><\/span><\/span>pot\u00eancia m\u00e9dia de <\/b><\/span><\/span><\/span>110 W<\/b><\/span><\/span><\/span> e fica ligada <\/b><\/span><\/span><\/span>24 h por dia<\/b><\/span><\/span><\/span>.<\/b><\/span><\/span><\/span> O <\/b><\/span><\/span><\/span>valor pago<\/b><\/span><\/span><\/span> para manter essa <\/b><\/span><\/span><\/span>geladeira ligada durante todo o m\u00eas<\/b><\/span><\/span><\/span> \u00e9:<\/b><\/span><\/span><\/span><\/p>\n

A)<\/b><\/span><\/span><\/span> R$58,91. <\/b><\/span><\/span><\/span>B)<\/b><\/span><\/span><\/span> R$47,52. <\/b><\/span><\/span><\/span>C)<\/b><\/span><\/span><\/span> R$36,53 <\/b><\/span><\/span><\/span>D)<\/b><\/span><\/span><\/span> R$ 40,14<\/b><\/span><\/span><\/span><\/p>\n

08-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

A <\/b><\/span><\/span><\/span>bicicleta ergom\u00e9trica<\/b><\/span><\/span><\/span> \u00e9 um aparelho muito usado nas academias. As mais modernas possuem um<\/b><\/span><\/span><\/span><\/p>\n

computador com um visor que informa o tempo, dist\u00e2ncia percorrida, batimentos card\u00edacos e as calorias gastas entre outras fun\u00e7\u00f5es.<\/b><\/span><\/span><\/span> Em uma academia, uma jovem anda em uma bicicleta <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

ergom\u00e9trica que n\u00e3o tem<\/b><\/span><\/span><\/span> <\/b>motor. O <\/b><\/span><\/span><\/span>visor informa que ela se exercitou a uma velocidade constante de <\/b><\/span><\/span><\/span>15 km\/h por 30 minutos<\/b><\/span><\/span><\/span> e que <\/b><\/span><\/span><\/span>250 kcal<\/b><\/span><\/span><\/span> foram consumidas.<\/b><\/span><\/span><\/span> Considerando-se que a <\/b><\/span><\/span><\/span>energia<\/b><\/span><\/span><\/span> <\/b>consumida<\/b><\/span><\/span><\/span> pela bicicleta ergom\u00e9trica se deve \u00e0<\/b><\/span><\/span><\/span> for\u00e7a constante que a jovem exerceu para moviment\u00e1-la, a intensidade dessa for\u00e7a, em Newtons, \u00e9,<\/b><\/span><\/span><\/span>aproximadamente:<\/b><\/span><\/span><\/span><\/p>\n

1 cal = 4 J.<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

09-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Na figura a seguir<\/b><\/span><\/span><\/span>, temos um <\/b><\/span><\/span><\/span>modelo muito simplificado de um motor de corrente cont\u00ednua<\/b><\/span><\/span><\/span>, como os<\/b><\/span><\/span><\/span><\/p>\n

motores <\/b><\/span><\/span><\/span>de arranque<\/b><\/span><\/span><\/span> dos autom\u00f3veis. Uma <\/b><\/span><\/span><\/span>espira retangular<\/b><\/span><\/span><\/span>, que est\u00e1 sendo percorrida por uma <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

corrente i, est\u00e1 <\/b><\/span><\/span><\/span>colocada numa <\/b><\/span><\/span><\/span>regi\u00e3o de campo magn\u00e9tico<\/b><\/span><\/span><\/span>. Dessa maneira, a espira \u00e9 capaz de <\/b><\/span><\/span><\/span>girar em torno do eixo y.<\/b><\/span><\/span><\/span><\/p>\n

Entre as afirmativas abaixo, assinale a <\/b><\/span><\/span><\/span>CORRETA.<\/b><\/span><\/span><\/span><\/p>\n

A)<\/b><\/span><\/span><\/span> A for\u00e7a magn\u00e9tica resultante na espira \u00e9 zero, por\u00e9m o torque resultante \u00e9 diferente de zero.<\/b><\/span><\/span><\/span><\/p>\n

B)<\/b><\/span><\/span><\/span> A for\u00e7a magn\u00e9tica nos lados b e d da espira \u00e9 nula.<\/b><\/span><\/span><\/span><\/p>\n

C)<\/b><\/span><\/span><\/span> O campo magn\u00e9tico na regi\u00e3o da espira est\u00e1 no sentido negativo de x.<\/b><\/span><\/span><\/span><\/p>\n

D)<\/b><\/span><\/span><\/span> A for\u00e7a magn\u00e9tica nos lados a e c da espira \u00e9 diferente em m\u00f3dulo.<\/b><\/span><\/span><\/span><\/p>\n

10-(UNIMONTES-MG-015)<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Em 1924, o F\u00edsico franc\u00eas <\/b><\/span><\/span><\/span>Louis de Broglie<\/b><\/span><\/span><\/span>, em sua tese de Doutorado, formulou a hip\u00f3tese de que <\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

a <\/b><\/span><\/span><\/span>mat\u00e9ria teria um comprimento de onda \u03bb associado a ela, dado pela express\u00e3o <\/b><\/span><\/span><\/span>\u03bb = h\/mv,<\/b><\/span><\/span><\/span> sendo <\/b><\/span><\/span><\/span>m <\/b><\/span><\/span><\/span>a massa da part\u00edcula material considerada, <\/b><\/span><\/span><\/span>h = 6,63 \u00d7 10<\/b><\/span><\/span><\/span>-34<\/b><\/span><\/span><\/sup><\/span> J.s<\/b><\/span><\/span><\/span> a <\/b><\/span><\/span><\/span>constante de Planck<\/b><\/span><\/span><\/span> e <\/b><\/span><\/span><\/span>v<\/b><\/span><\/span><\/span> sua<\/b><\/span><\/span><\/span> <\/b>velocidade.<\/b><\/span><\/span><\/span> Considerada a hip\u00f3tese de \u2018de Broglie\u2019, um <\/b><\/span><\/span><\/span>el\u00e9tron<\/b><\/span><\/span><\/span> que se move a uma <\/b><\/span><\/span><\/span>velocidade de m\u00f3dulo <\/b><\/span><\/span><\/span>7,28 \u00d7 10<\/b><\/span><\/span><\/span>6<\/b><\/span><\/span><\/sup><\/span> m\/s<\/b><\/span><\/span><\/span> manifesta uma onda de mat\u00e9ria cujo <\/b><\/span><\/span><\/span>comprimento de onda \u00e9 da ordem de<\/b><\/span><\/span><\/span><\/p>\n

Dado: m = 9,14.10<\/b><\/span><\/span><\/span>-31<\/b><\/span><\/span><\/sup><\/span> kg.<\/b><\/span><\/span><\/span><\/p>\n

A)<\/b><\/span><\/span><\/span> 10<\/b><\/span><\/span><\/span>-8<\/b><\/span><\/span><\/sup><\/span> m. <\/b><\/span><\/span><\/span>B) <\/b><\/span><\/span><\/span>10<\/b><\/span><\/span><\/span>-12<\/b><\/span><\/span><\/sup><\/span> m. <\/b><\/span><\/span><\/span>C)<\/b><\/span><\/span><\/span> 10<\/b><\/span><\/span><\/span>-14<\/b><\/span><\/span><\/sup><\/span> m <\/b><\/span><\/span><\/span>D) <\/b><\/span><\/span><\/span>10<\/b><\/span><\/span><\/span>-10<\/b><\/span><\/span><\/sup><\/span> m<\/b><\/span><\/span><\/span><\/p>\n

<\/h2>\n

Confira a resolu\u00e7\u00e3o comentada.<\/span><\/a><\/h2>\n","protected":false},"excerpt":{"rendered":"

A\u00a0Universidade Estadual de Montes Claros\u00a0–\u00a0UNIMONTES\u00a0\u00e9 uma institui\u00e7\u00e3o p\u00fablica de ensino superior, sediada em Montes Claros – MG, tendo sob \u00e1rea de influ\u00eancia o Norte e Noroeste de Minas Gerais,\u00a0Vale do Mucuri,\u00a0Vale do Jequitinhonha, al\u00e9m de parte da Serra Geral, regi\u00e3o Centro-Sul da\u00a0Bahia. Localizada na cidade de Montes Claros, centro convergente e polarizador dos demais munic\u00edpios da regi\u00e3o do Norte de<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":5,"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-712","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/712","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=712"}],"version-history":[{"count":3,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/712\/revisions"}],"predecessor-version":[{"id":11003,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/712\/revisions\/11003"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/5"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=712"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}