{"id":4854,"date":"2020-01-09T14:13:31","date_gmt":"2020-01-09T14:13:31","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=4854"},"modified":"2024-06-30T00:13:20","modified_gmt":"2024-06-30T00:13:20","slug":"eletromagnetismo-2018-2019","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/vestibulares-recentes\/eletricidade\/eletromagnetismo-2018-2019\/","title":{"rendered":"ELETROMAGNETISMO \u2013 2018\/2019"},"content":{"rendered":"

ELETROMAGNETISMO \u2013 2018\/2019<\/b><\/span><\/span><\/span><\/p>\n

Im\u00e3s, Campo Magn\u00e9tico e For\u00e7a Magn\u00e9tica<\/b><\/span><\/span><\/span><\/p>\n

01- (URCA-CE-019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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A)<\/b><\/span><\/span>Em ambos os casos podemos rejuntar os peda\u00e7os conforme as posi\u00e7\u00f5es que est\u00e3o.<\/b><\/span><\/span><\/span><\/span><\/p>\n

B)\u00a0<\/b><\/span><\/span>Somente no corte longitudinal podem-se rejuntar os peda\u00e7os,<\/b><\/span><\/span><\/span><\/span><\/p>\n

C)\u00a0<\/b><\/span><\/span>N\u00e3o tem como rejuntar os peda\u00e7os do corte transversal porque provem do mesmo \u00edm\u00e3.<\/b><\/span><\/span><\/span><\/span><\/p>\n

D)<\/b><\/span><\/span>Somente os cortes transversais podem rejuntar.<\/b><\/span><\/span><\/span><\/span><\/p>\n

E)\u00a0<\/b><\/span><\/span>Ambos podem se rejuntar, por\u00e9m, o corte transversal se juntam os lados conforme eles estavam originalmente e, o corte longitudinal, temos que inverter um dos \u00edm\u00e3s.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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02- Universidade Federal de Uberl\u00e2ndia\u00a0\u2013\u00a0UFU\u00a0\u2013 MG \u2013 meio do ano \u2013 2019\/2020<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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Al\u00e9m de poderem ser observados em pequenos objetos e m\u00e1quinas constru\u00eddas pelo homem, os campos magn\u00e9ticos tamb\u00e9m est\u00e3o presentes em escala astron\u00f4mica.<\/b><\/span><\/span><\/span><\/span><\/p>\n

As\u00a0<\/b><\/span><\/span>estrelas, como o Sol, produzem intensos campos, criando ao seu redor o que se chama de magnetosfera. [\u2026.]<\/b><\/span><\/span><\/span><\/span><\/p>\n

Existem objetos estelares capazes de produzir campos magn\u00e9ticos absurdamente altos, como o que ocorre nos pulsares \u2013 restos mortais de estrelas gigantes, constitu\u00eddos apenas por n\u00eautrons. S\u00e3o campos magn\u00e9ticos na ordem de 100 milh\u00f5es de Tesla! Perto deles, o campo magn\u00e9tico produzido pela Terra \u00e9 quase nada: sua intensidade est\u00e1 na ordem de 0,0001 Tesla, bem menor do que a do \u00edm\u00e3 de geladeira.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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Mesmo assim,\u00a0<\/b><\/span><\/span>o campo magn\u00e9tico terrestre \u00e9 de fundamental import\u00e2ncia para o desenvolvimento da vida por aqui. O fato de o planeta possuir um campo magn\u00e9tico impede que part\u00edculas com alta energia, vindas do espa\u00e7o interestelar ou do pr\u00f3prio Sol, atinjam a superf\u00edcie terrestre, o que poderia ser prejudicial a diversas formas de vida, inclusive a nossa.\u00a0<\/b><\/span><\/span>http:\/\/cienciahoje.org.br\/coluna\/da-geladeira-ao-espaco-sideral\/. Acesso em 02.mar.2019. (Adaptado)<\/b><\/span><\/span><\/span><\/span><\/p>\n

A respeito do magnetismo terrestre, s\u00e3o feitas as seguintes afirma\u00e7\u00f5es.<\/b><\/span><\/span><\/span><\/span><\/p>\n

I.<\/b><\/span><\/span>\u00a0As\u00a0<\/b><\/span><\/span>part\u00edculas com alta energia, vindas do espa\u00e7o interestelar ou do pr\u00f3prio Sol,\u00a0<\/b><\/span><\/span>citadas no texto,\u00a0<\/b><\/span><\/span>quando eletrizadas\u00a0<\/b><\/span><\/span>e\u00a0<\/b><\/span><\/span>sob a a\u00e7\u00e3o do campo magn\u00e9tico terrestre, s\u00e3o respons\u00e1veis pela forma\u00e7\u00e3o das auroras polares.<\/b><\/span><\/span><\/span><\/span><\/p>\n

II.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>As\u00a0<\/b><\/span><\/span>b\u00fassolas s\u00e3o pequenos im\u00e3s que, quando livres, alinham-se com o campo magn\u00e9tico terrestre citado no texto e se posicionam aproximadamente na dire\u00e7\u00e3o Norte-Sul do planeta.<\/b><\/span><\/span><\/span><\/span><\/p>\n

III.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>O\u00a0<\/b><\/span><\/span>campo magn\u00e9tico terrestre, apesar de baixa intensidade, como citado no texto, possui m\u00f3dulo, dire\u00e7\u00e3o e sentido constantes em todos os pontos da superf\u00edcie da Terra, fato esse que possibilita seu uso na orienta\u00e7\u00e3o de viajantes em qualquer posi\u00e7\u00e3o do planeta<\/b><\/span><\/span>.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Em\u00a0<\/b><\/span><\/span>rela\u00e7\u00e3o \u00e0s afirma\u00e7\u00f5es acima, marque V para as verdadeiras e F para as falsas e assinale a alternativa correta.<\/b><\/span><\/span><\/span><\/span><\/p>\n

A)\u00a0<\/b><\/span><\/span>I \u2013 F; II \u2013 V; III \u2013 V.<\/b><\/span><\/span><\/span><\/span><\/p>\n

B)\u00a0<\/b><\/span><\/span>I \u2013 V; II \u2013 V; III \u2013 F.<\/b><\/span><\/span><\/span><\/span><\/p>\n

C)\u00a0<\/b><\/span><\/span>I \u2013 V; II \u2013 F; III \u2013 V.<\/b><\/span><\/span><\/span><\/span><\/p>\n

D)\u00a0<\/b><\/span><\/span>I \u2013 F; II \u2013 F; III \u2013 F.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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03- FAMERP 2019 \u2013 Conhecimentos Gerais<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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Tr\u00eas \u00edm\u00e3s id\u00eanticos<\/b><\/span><\/span>, em forma de barra,\u00a0<\/b><\/span><\/span>est\u00e3o dispostos com uma de suas extremidades equidistantes de um ponto P<\/b><\/span><\/span>, como mostra a figura.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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O campo de indu\u00e7\u00e3o magn\u00e9tica resultante da a\u00e7\u00e3o dos tr\u00eas \u00edm\u00e3s no ponto P \u00e9 representado pelo vetor<\/b><\/span><\/span><\/span><\/span><\/p>\n

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04-(Faculdade de Medicina de Taubat\u00e9 \u2013 FMT \u2013 019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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Uma\u00a0<\/b><\/span><\/span>part\u00edcula com carga positiva \u00e9 injetada com velocidade V numa regi\u00e3o com campos el\u00e9trico e magn\u00e9tico cruzados e passa a se movimentar em uma trajet\u00f3ria retil\u00ednea.<\/b><\/span><\/span><\/span><\/span><\/p>\n

O\u00a0<\/b><\/span><\/span>campo magn\u00e9tico \u00e9 um vetor que sai perpendicularmente \u00e0 folha do papel, enquanto o campo el\u00e9trico \u00e9 paralelo \u00e0 folha, conforme apresentado\u00a0<\/b><\/span><\/span>na figura abaixo.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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Sabendo que\u00a0<\/b><\/span><\/span>E e B s\u00e3o os m\u00f3dulos dos campos el\u00e9trico e magn\u00e9tico, determine o m\u00f3dulo da velocidade V nessa regi\u00e3o e assinale a alternativa CORRETA.<\/b><\/span><\/span><\/span><\/span><\/p>\n

a)\u00a0<\/b><\/span><\/span>V = E\/B<\/b><\/span><\/span><\/span><\/span><\/p>\n

b)\u00a0<\/b><\/span><\/span>V = B\/E<\/b><\/span><\/span><\/span><\/span><\/p>\n

c)\u00a0<\/b><\/span><\/span>V = EB<\/b><\/span><\/span><\/span><\/span><\/p>\n

d)\u00a0<\/b><\/span><\/span>V = E\/B2<\/b><\/span><\/span><\/span><\/span><\/p>\n

e)\u00a0<\/b><\/span><\/span>V = B\/E2<\/b><\/span><\/span><\/span><\/span><\/p>\n

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05- (Escola de Especialistas de Aeron\u00e1utica\u00a0\u2013\u00a0EEAR\u00a0\u2013 019\/020)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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Uma\u00a0<\/b><\/span><\/span>part\u00edcula com carga el\u00e9trica igual a 3,2\u00a0<\/b><\/span><\/span>\uf06d<\/b><\/span><\/span>C e velocidade de 2.104\u00a0m\/s \u00e9 lan\u00e7ada perpendicularmente a um campo magn\u00e9tico uniforme\u00a0<\/b><\/span><\/span>e\u00a0<\/b><\/span><\/span>sofre a a\u00e7\u00e3o de uma for\u00e7a magn\u00e9tica de intensidade igual a 1,6 .102\u00a0N.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Determine a intensidade do campo magn\u00e9tico\u00a0<\/b><\/span><\/span>(em Tesla)\u00a0<\/b><\/span><\/span>no qual a part\u00edcula foi lan\u00e7ada.<\/b><\/span><\/span><\/span><\/span><\/p>\n

a)\u00a0<\/b><\/span><\/span>0,25.103<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>b)\u00a0<\/b><\/span><\/span>2,5.103<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>c)\u00a0<\/b><\/span><\/span>2,5.104<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>d)\u00a0<\/b><\/span><\/span>0,25.106<\/b><\/span><\/span><\/span><\/span><\/p>\n

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06- Universidade Estadual de Maring\u00e1\u00a0(UEM) \u2013 019<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

\u00a0<\/span><\/p>\n

Um\u00a0<\/b><\/span><\/span>feixe de part\u00edculas id\u00eanticas eletrizadas est\u00e1 descrevendo uma trajet\u00f3ria circular\u00a0<\/b><\/span><\/span>(no v\u00e1cuo)\u00a0<\/b><\/span><\/span>em um campo magn\u00e9tico constante e uniforme\u00a0<\/b><\/span><\/span>de\u00a0<\/b><\/span><\/span>m\u00f3dulo B = 7.10-2\u00a0T.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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Considerando que a\u00a0<\/b><\/span><\/span>carga de cada part\u00edcula \u00e9 q = 4.10-6\u00a0C\u00a0<\/b><\/span><\/span>e que essas\u00a0<\/b><\/span><\/span>part\u00edculas se movem com velocidade (em m\u00f3dulo) v = 2.102\u00a0m\/s, assinale<\/b><\/span><\/span>\u00a0o que\u00a0<\/b><\/span><\/span>for correto.<\/b><\/span><\/span><\/span><\/span><\/p>\n

01)<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>O \u00e2ngulo entre o vetor velocidade das part\u00edculas e o vetor que representa o campo magn\u00e9tico deve mudar a cada instante, visto que o movimento \u00e9 circular.<\/b><\/span><\/span><\/span><\/span><\/p>\n

02)<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>O m\u00f3dulo da for\u00e7a magn\u00e9tica que atua em cada part\u00edcula \u00e9 F = 5.10-5\u00a0N.<\/b><\/span><\/span><\/span><\/span><\/p>\n

04)<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Para cada part\u00edcula, a for\u00e7a magn\u00e9tica corresponde \u00e0 for\u00e7a resultante centr\u00edpeta.<\/b><\/span><\/span><\/span><\/span><\/p>\n

08)<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>O m\u00f3dulo da quantidade de movimento e a energia cin\u00e9tica de cada part\u00edcula s\u00e3o constantes.<\/b><\/span><\/span><\/span><\/span><\/p>\n

16)<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Medindo-se o raio da trajet\u00f3ria circular, podemos calcular a massa de cada part\u00edcula.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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07- Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia do Norte de Minas Gerais\u00a0(IFNMG)- 2019<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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Um\u00a0<\/b><\/span><\/span>estudante analisou o experimento ilustrado na figura abaixo.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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Sobre esse experimento, em que um el\u00e9tron, inicialmente com velocidade de valor vo, penetra em uma regi\u00e3o material e<\/b><\/span><\/span><\/span><\/span><\/p>\n

submete-se a um campo magn\u00e9tico\u00a0B,<\/b><\/span><\/span>\u00a0o estudante\u00a0<\/b><\/span><\/span>escreveu:<\/b><\/span><\/span>\u00a0\u201cA\u00a0<\/b><\/span><\/span>dire\u00e7\u00e3o de\u00a0B\u00a0\u00e9 perpendicular ao plano da figura,<\/b><\/span><\/span>\u00a0o seu\u00a0<\/b><\/span><\/span>sentido \u00e9 para\u00a0<\/b><\/span><\/span>________\u00a0<\/b><\/span><\/span>desse plano\u00a0<\/b><\/span><\/span>e sua\u00a0<\/b><\/span><\/span>velocidade no ponto P<\/b><\/span><\/span>\u00a0\u00e9 _________\u00a0<\/b><\/span><\/span>vo\u201d.\u00a0<\/b><\/span><\/span>O\u00a0<\/b><\/span><\/span>texto do estudante estar\u00e1<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>correto se as lacunas nele presentes forem preenchidas, respectivamente, com os termos:<\/b><\/span><\/span><\/span><\/span><\/p>\n

A)\u00a0<\/b><\/span><\/span>dentro; menor que<\/b><\/span><\/span><\/span><\/span><\/p>\n

B)\u00a0<\/b><\/span><\/span>dentro; igual a<\/b><\/span><\/span><\/span><\/span><\/p>\n

C)\u00a0<\/b><\/span><\/span>fora; maior que<\/b><\/span><\/span><\/span><\/span><\/p>\n

D)\u00a0<\/b><\/span><\/span>fora, igual a<\/b><\/span><\/span><\/span><\/span><\/p>\n

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08- (UFAM-AM-2019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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09- (UNIFOR- Medicina \u2013 CE-019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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O\u00a0<\/b><\/span><\/span>controle dos anest\u00e9sicos gerais no organismo do paciente\u00a0<\/b><\/span><\/span>\u00e9 muito\u00a0<\/b><\/span><\/span>importante em cirurgias.<\/b><\/span><\/span><\/span><\/span><\/p>\n

As\u00a0<\/b><\/span><\/span>concentra\u00e7\u00f5es alveolares podem ser monitoradas continuamente\u00a0<\/b><\/span><\/span>pela medida da\u00a0<\/b><\/span><\/span>concentra\u00e7\u00e3o expirat\u00f3ria final do anest\u00e9sico por meio da espectrometria de massa.<\/b><\/span><\/span><\/span><\/span><\/p>\n

A espectrometria de massas \u00e9 uma t\u00e9cnica anal\u00edtica f\u00edsica para detectar e identificar mol\u00e9culas de interesse<\/b><\/span><\/span>\u00a0por meio da\u00a0<\/b><\/span><\/span>medi\u00e7\u00e3o da sua massa e da caracteriza\u00e7\u00e3o de sua estrutura qu\u00edmica<\/b><\/span><\/span>. Os\u00a0<\/b><\/span><\/span>anestesistas usam um tipo de espectr\u00f4metro de massa na sala de opera\u00e7\u00f5es para monitorar os gases respirat\u00f3rios de pacientes submetidos \u00e0 cirurgia.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Nesse processo, o\u00a0<\/b><\/span><\/span>g\u00e1s \u00e9 aspirado para uma c\u00e2mera \u00e0 v\u00e1cuo, onde \u00e9 bombardeado por um feixe ionizante, os \u00edons s\u00e3o ent\u00e3o acelerados por um campo el\u00e9trico e expostos a um campo magn\u00e9tico na c\u00e2mera de dispers\u00e3o,\u00a0<\/b><\/span><\/span>onde\u00a0<\/b><\/span><\/span>apresentam uma deflex\u00e3o em sua trajet\u00f3ria,\u00a0<\/b><\/span><\/span>cuja\u00a0<\/b><\/span><\/span>curvatura \u00e9 proporcional \u00e0 rela\u00e7\u00e3o entre a carga e a massa, como mostrado na figura.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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Ou seja, os\u00a0<\/b><\/span><\/span>\u00edons mais leves ir\u00e3o defletir menos, produzindo uma trajet\u00f3ria em arco de menor raio.<\/b><\/span><\/span>\u00a0Um\u00a0<\/b><\/span><\/span>g\u00e1s<\/b><\/span><\/span>\u00a0que \u00e9\u00a0<\/b><\/span><\/span>frequentemente monitorado \u00e9 o isoflurano,<\/b><\/span><\/span>\u00a0um\u00a0<\/b><\/span><\/span>anest\u00e9sico inalat\u00f3rio\u00a0<\/b><\/span><\/span>que possui\u00a0<\/b><\/span><\/span>massa molecular igual a 3,0 x 10-25\u00a0kg.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Uma\u00a0<\/b><\/span><\/span>mol\u00e9cula ionizada desse g\u00e1s com carga 1,6 x 10-19C\u00a0<\/b><\/span><\/span>se\u00a0<\/b><\/span><\/span>move<\/b><\/span><\/span>\u00a0com\u00a0<\/b><\/span><\/span>velocidade de 8,0 x 103\u00a0m\/s, perpendicular ao campo magn\u00e9tico,<\/b><\/span><\/span>\u00a0em uma\u00a0<\/b><\/span><\/span>trajet\u00f3ria circular de raio 0,10 metros<\/b><\/span><\/span>.\u00a0<\/b><\/span><\/span>Qual o m\u00f3dulo do campo magn\u00e9tico utilizado por esse espectr\u00f4metro?<\/b><\/span><\/span><\/span><\/span><\/p>\n

(A)\u00a0<\/b><\/span><\/span>0,10 T\u00a0<\/b><\/span><\/span>(B)\u00a0<\/b><\/span><\/span>0,13 T\u00a0<\/b><\/span><\/span>(C)\u00a0<\/b><\/span><\/span>0,15 T\u00a0<\/b><\/span><\/span>(D)\u00a0<\/b><\/span><\/span>0,17 T\u00a0<\/b><\/span><\/span>(E)\u00a0<\/b><\/span><\/span>0,19 T<\/b><\/span><\/span><\/span><\/span><\/p>\n

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10-(FPS-Faculdade Pernambucana de Sa\u00fade-PE-2019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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11- (FMABC-SP-018)<\/b><\/span><\/span><\/span><\/p>\n

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Ao\u00a0<\/b><\/span><\/span><\/span>penetrar com velocidade v<\/b><\/span><\/span><\/span>\u00a0em uma\u00a0<\/b><\/span><\/span><\/span>regi\u00e3o na qual existe um campo de indu\u00e7\u00e3o magn\u00e9tica uniforme de intensidade B,\u00a0<\/b><\/span><\/span><\/span>uma\u00a0<\/b><\/span><\/span><\/span>part\u00edcula eletrizada com carga positiva q sofre\u00a0<\/b><\/span><\/span><\/span>a\u00a0<\/b><\/span><\/span><\/span>a\u00e7\u00e3o\u00a0<\/b><\/span><\/span><\/span>de uma\u00a0<\/b><\/span><\/span><\/span>for\u00e7a de intensidade F,\u00a0<\/b><\/span><\/span><\/span>devida a\u00a0<\/b><\/span><\/span><\/span>esse campo.<\/b><\/span><\/span><\/span><\/p>\n

Considerando-se\u00a0<\/b><\/span><\/span><\/span>v, B e q constantes,\u00a0<\/b><\/span><\/span><\/span>a\u00a0<\/b><\/span><\/span><\/span>intensidade da for\u00e7a depende apenas do \u00e2ngulo<\/b><\/span><\/span><\/span>\u00a0entre as\u00a0<\/b><\/span><\/span><\/span>dire\u00e7\u00f5es do campo e da velocidade da part\u00edcula.<\/b><\/span><\/span><\/span><\/p>\n

O\u00a0<\/b><\/span><\/span><\/span>gr\u00e1fico que mostra a rela\u00e7\u00e3o entre a intensidade da for\u00e7a e \u00e2ngulo\u00a0<\/b><\/span><\/span><\/span>\u00e9<\/b><\/span><\/span><\/span><\/p>\n

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12- (EsPCEx- AMAN \u2013 2017\/18)<\/b><\/span><\/span><\/span><\/p>\n

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Uma\u00a0<\/b><\/span><\/span><\/span>carga el\u00e9trica puntiforme,\u00a0<\/b><\/span><\/span><\/span>no\u00a0<\/b><\/span><\/span><\/span>interior de um campo magn\u00e9tico uniforme e constante,<\/b><\/span><\/span><\/span><\/p>\n

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dependendo\u00a0<\/b><\/span><\/span><\/span>de suas\u00a0<\/b><\/span><\/span><\/span>condi\u00e7\u00f5es cinem\u00e1ticas,\u00a0<\/b><\/span><\/span><\/span>pode ficar\u00a0<\/b><\/span><\/span><\/span>sujeita \u00e0 a\u00e7\u00e3o de uma for\u00e7a magn\u00e9tica.\u00a0<\/b><\/span><\/span><\/span>Sobre\u00a0<\/b><\/span><\/span><\/span>essa for\u00e7a pode-se afirmar\u00a0<\/b><\/span><\/span><\/span>que<\/b><\/span><\/span><\/span><\/p>\n

[A]\u00a0<\/b><\/span><\/span><\/span>tem a mesma dire\u00e7\u00e3o do campo magn\u00e9tico, se a carga el\u00e9trica tiver velocidade perpendicular a ele.<\/b><\/span><\/span><\/span><\/p>\n

[B]\u00a0<\/b><\/span><\/span><\/span>\u00e9 nula se a carga el\u00e9trica estiver em repouso.<\/b><\/span><\/span><\/span><\/p>\n

[C]\u00a0<\/b><\/span><\/span><\/span>tem m\u00e1xima intensidade se o campo magn\u00e9tico e a velocidade da carga el\u00e9trica forem paralelos.\u00a0<\/b><\/span><\/span><\/span>[D]\u00a0<\/b><\/span><\/span><\/span>\u00e9 nula se o campo magn\u00e9tico e a velocidade da carga el\u00e9trica forem perpendiculares.<\/b><\/span><\/span><\/span><\/p>\n

[E]\u00a0<\/b><\/span><\/span><\/span>tem a mesma dire\u00e7\u00e3o da velocidade da carga el\u00e9trica<\/b><\/span><\/span><\/span><\/p>\n

13- UEG \u2013 GO \u2013 2018<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

A figura a seguir descreve uma regi\u00e3o do espa\u00e7o que cont\u00e9m um vetor campo el\u00e9trico\u00a0\u00a0e um vetor campo magn\u00e9tico.<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Mediante um ajuste, percebe-se que,\u00a0<\/b><\/span><\/span><\/span>quando os campos el\u00e9tricos e magn\u00e9ticos assumem valores de 1,0.103\u00a0N\/C e 2,0.10-2\u00a0T,<\/b><\/span><\/span><\/span>\u00a0respectivamente,\u00a0<\/b><\/span><\/span><\/span>um \u00edon positivo, de massa desprez\u00edvel, atravessa os campos em linha reta.\u00a0<\/b><\/span><\/span><\/span>A\u00a0<\/b><\/span><\/span><\/span>velocidade desse \u00edon,\u00a0<\/b><\/span><\/span><\/span>em m\/s, foi de<\/b><\/span><\/span><\/span><\/p>\n

a) 5,0.104<\/b><\/span><\/span><\/span><\/p>\n

b) 1,0.105<\/b><\/span><\/span><\/span><\/p>\n

c) 2,0.103<\/b><\/span><\/span><\/span><\/p>\n

d) 3,0.103<\/b><\/span><\/span><\/span><\/p>\n

e) 1,0.104<\/b><\/span><\/span><\/span><\/p>\n

Campo Magn\u00e9tico originado por um fio retil\u00edneo<\/b><\/span><\/span><\/span><\/p>\n

\u00a0<\/span><\/p>\n

14- (Faculdade de Ci\u00eancias M\u00e9dicas da Santa Casa de S\u00e3o Paulo \u2013 SP \u2013 019)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

<\/p>\n

15- (MEDICINA -UNIVERSIDADE MUNICIPAL DE S\u00c3O CAETANO DO SUL \u2013\u2013 USCS-SP \u2013 019)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

A\u00a0<\/b><\/span><\/span><\/span>figura mostra dois fios condutores, longos e retil\u00edneos, dispostos perpendicularmente um ao outro, situados num mesmo plano e percorridos por correntes el\u00e9tricas cont\u00ednuas de mesma intensidade I.<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

As\u00a0<\/b><\/span><\/span><\/span>correntes que percorrem os fios produzem no ponto P, situado no mesmo plano dos fios, um campo magn\u00e9tico resultante,\u00a0<\/b><\/span><\/span><\/span>que \u00e9\u00a0<\/b><\/span><\/span><\/span>representado por um vetor<\/b><\/span><\/span><\/span><\/p>\n

(A)\u00a0<\/b><\/span><\/span><\/span>perpendicular ao plano determinado pelos fios, entrando nele.<\/b><\/span><\/span><\/span><\/p>\n

(B)\u00a0<\/b><\/span><\/span><\/span>perpendicular ao plano determinado pelos fios, saindo dele.<\/b><\/span><\/span><\/span><\/p>\n

(C)\u00a0<\/b><\/span><\/span><\/span>que est\u00e1 contido no plano determinado pelos fios, sendo paralelo ao fio mais pr\u00f3ximo.<\/b><\/span><\/span><\/span><\/p>\n

(D)\u00a0<\/b><\/span><\/span><\/span>nulo.<\/b><\/span><\/span><\/span><\/p>\n

(E)\u00a0<\/b><\/span><\/span><\/span>que est\u00e1 contido no plano determinado pelos fios, n\u00e3o sendo paralelo a nenhum deles.<\/b><\/span><\/span><\/span><\/p>\n

16- (Faculdade de Tecnologia do Estado de S\u00e3o Paulo\u00a0\u2013 FATEC \u2013 019)<\/b><\/span><\/span><\/span><\/p>\n

\u00a0<\/span><\/p>\n

Dois fios condutores id\u00eanticos, paralelos entre si,\u00a0<\/b><\/span><\/span><\/span>e de\u00a0<\/b><\/span><\/span><\/span>comprimento infinito s\u00e3o percorridos simultaneamente por correntes el\u00e9tricas de mesmo sentido e de mesma intensidade.<\/b><\/span><\/span><\/span><\/p>\n

Considere que\u00a0<\/b><\/span><\/span><\/span>eles estejam dispostos perpendiculares ao plano do papel desta prova.<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Nessas condi\u00e7\u00f5es, \u00e9 correto afirmar<\/b><\/span><\/span><\/span>\u00a0que<\/b><\/span><\/span><\/span><\/p>\n

(A)\u00a0<\/b><\/span><\/span><\/span>geram campos magn\u00e9ticos perpendiculares ao plano do papel.<\/b><\/span><\/span><\/span><\/p>\n

(B)\u00a0<\/b><\/span><\/span><\/span>geram campos magn\u00e9ticos circulares ao plano do papel.<\/b><\/span><\/span><\/span><\/p>\n

(C)\u00a0<\/b><\/span><\/span><\/span>geram campos magn\u00e9ticos repulsivos entre si.<\/b><\/span><\/span><\/span><\/p>\n

(D)\u00a0<\/b><\/span><\/span><\/span>sofrem entre si uma for\u00e7a de repuls\u00e3o.<\/b><\/span><\/span><\/span><\/p>\n

(E)\u00a0<\/b><\/span><\/span><\/span>sofrem entre si uma for\u00e7a de atra\u00e7\u00e3o.<\/b><\/span><\/span><\/span><\/p>\n

17- (Universidade Estadual do Centro-Oeste do Paran\u00e1 \u2013\u00a0UNICENTRO \u2013 019)<\/b><\/span><\/span><\/span><\/p>\n

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Descargas el\u00e9tricas atmosf\u00e9ricas, tamb\u00e9m conhecidas por raios<\/b><\/span><\/span><\/span>, podem\u00a0<\/b><\/span><\/span><\/span>ser perigosas de muitas formas, pois a corrente el\u00e9trica produzida por um raio pode chegar a 4.105\u00a0A.<\/b><\/span><\/span><\/span><\/p>\n

Imaginando que essa corrente poderia fluir por um fio, calcule a intensidade do vetor indu\u00e7\u00e3o magn\u00e9tico gerado por ela a uma dist\u00e2ncia de 8 cm do condutor<\/b><\/span><\/span><\/span>, e\u00a0<\/b><\/span><\/span><\/span>marque a alternativa correta.\u00a0<\/b><\/span><\/span><\/span>(<\/b><\/span><\/span><\/span>Dado:<\/b><\/span><\/span><\/span>\u00a0\u00b50\u00a0= 4\u03c0.10-7\u00a0T.m\/A)<\/b><\/span><\/span><\/span><\/p>\n

a)\u00a0<\/b><\/span><\/span><\/span>0,001 T\u00a0<\/b><\/span><\/span><\/span>b)\u00a0<\/b><\/span><\/span><\/span>10 . 10-5\u00a0T\u00a0<\/b><\/span><\/span><\/span>c)\u00a0<\/b><\/span><\/span><\/span>10 T.\u00a0<\/b><\/span><\/span><\/span>d)\u00a0<\/b><\/span><\/span><\/span>0,01 T\u00a0<\/b><\/span><\/span><\/span>e)\u00a0<\/b><\/span><\/span><\/span>1 T<\/b><\/span><\/span><\/span><\/p>\n

18- (<\/b><\/span><\/span><\/span>Instituto Federal de Educa\u00e7\u00e3o, Ci\u00eancia e Tecnologia<\/b><\/u><\/span><\/span><\/span><\/a>\u00a0de\u00a0<\/b><\/span><\/span><\/span>Roraima<\/b><\/u><\/span><\/span><\/span><\/a>\u00a0\u2013 RR \u2013 019)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Um\u00a0<\/b><\/span><\/span><\/span>fio met\u00e1lico vertical e extenso \u00e9 percorrido por uma corrente de intensidade 3 A. Calcule<\/b><\/span><\/span><\/span>\u00a0a\u00a0<\/b><\/span><\/span><\/span>intensidade do vetor indu\u00e7\u00e3o magn\u00e9tica em um ponto P, que dista 50 cm do fio<\/b><\/span><\/span><\/span>, como mostra a\u00a0<\/b><\/span><\/span><\/span>figura abaixo.<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Adote \u00b50\u00a0= 4\u03c0.10-7\u00a0T.m\/A.<\/b><\/span><\/span><\/span><\/p>\n

(A)\u00a0<\/b><\/span><\/span><\/span>2,4.10-6\u00a0T\u00a0<\/b><\/span><\/span><\/span>(B)\u00a0<\/b><\/span><\/span><\/span>1,8 . 10-6\u00a0T\u00a0<\/b><\/span><\/span><\/span>(C)\u00a0<\/b><\/span><\/span><\/span>4,6 . 10-6\u00a0T\u00a0<\/b><\/span><\/span><\/span>(D)\u00a0<\/b><\/span><\/span><\/span>3,4 . 10-6\u00a0T\u00a0<\/b><\/span><\/span><\/span>(E)\u00a0<\/b><\/span><\/span><\/span>1,2 . 10-6\u00a0T<\/b><\/span><\/span><\/span><\/p>\n

19- (Faculdade de Medicina do Hospital Israelita Albert Einstein-SP-018)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

<\/p>\n

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

20- (UNIFOR-CE-018)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Na\u00a0<\/b><\/span><\/span><\/span>figura abaixo,\u00a0<\/b><\/span><\/span><\/span>observam-se\u00a0<\/b><\/span><\/span><\/span>dois fios met\u00e1licos paralelos separados<\/b><\/span><\/span><\/span>\u00a0por uma\u00a0<\/b><\/span><\/span><\/span>dist\u00e2ncia de r = 2 m,\u00a0<\/b><\/span><\/span><\/span>no v\u00e1cuo.<\/b><\/span><\/span><\/span><\/p>\n

A\u00a0<\/b><\/span><\/span><\/span>corrente el\u00e9trica em cada fio \u00e9 i = 0,60 A da esquerda para a direita.<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

A\u00a0<\/b><\/span><\/span><\/span>dire\u00e7\u00e3o e a intensidade da for\u00e7a\u00a0<\/b><\/span><\/span><\/span>que\u00a0<\/b><\/span><\/span><\/span>age<\/b><\/span><\/span><\/span>\u00a0no\u00a0<\/b><\/span><\/span><\/span>comprimento L = 3,0 m de um dos fios\u00a0<\/b><\/span><\/span><\/span>(\u00a0o\u00a0= 4.10-7\u00a0unidades do SI)\u00a0<\/b><\/span><\/span><\/span>\u00e9<\/b><\/span><\/span><\/span><\/p>\n

(A) F = 0,54.10-7<\/b><\/span><\/span><\/span>\u00a0a for\u00e7a \u00e9 de\u00a0<\/b><\/span><\/span><\/span>repuls\u00e3o<\/b><\/span><\/span><\/span>\u00a0entre os dois fios.<\/b><\/span><\/span><\/span><\/p>\n

(B) F = 0,54.10-7<\/b><\/span><\/span><\/span>\u00a0<\/b><\/span><\/span><\/span>a for\u00e7a \u00e9 de\u00a0<\/b><\/span><\/span><\/span>atra\u00e7\u00e3o\u00a0<\/b><\/span><\/span><\/span>entre os dois fios.<\/b><\/span><\/span><\/span><\/p>\n

(C) F = 1,08.10-7<\/b><\/span><\/span><\/span>\u00a0<\/b><\/span><\/span><\/span>a for\u00e7a \u00e9 de\u00a0<\/b><\/span><\/span><\/span>repuls\u00e3o\u00a0<\/b><\/span><\/span><\/span>entre os dois fios.<\/b><\/span><\/span><\/span><\/p>\n

(D) F = 1,08.10-7<\/b><\/span><\/span><\/span>\u00a0<\/b><\/span><\/span><\/span>a for\u00e7a \u00e9 de\u00a0<\/b><\/span><\/span><\/span>atra\u00e7\u00e3o\u00a0<\/b><\/span><\/span><\/span>entre os dois fios.<\/b><\/span><\/span><\/span><\/p>\n

(E)\u00a0<\/b><\/span><\/span><\/span>A\u00a0<\/b><\/span><\/span><\/span>for\u00e7a\u00a0<\/b><\/span><\/span><\/span>entre os dois fios\u00a0<\/b><\/span><\/span><\/span>\u00e9 nula.<\/b><\/span><\/span><\/span><\/p>\n

Fluxo eletromagn\u00e9tico, corrente el\u00e9trica imduzida e for\u00e7a eletromotriz induzida<\/b><\/span><\/span><\/span><\/p>\n

21- (ENEM-MEC-018)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

A\u00a0<\/b><\/span><\/span>tecnologia de comunica\u00e7\u00e3o\u00a0<\/b><\/span><\/span>da\u00a0<\/b><\/span><\/span>etiqueta RFID (chamada de etiqueta inteligente)<\/b><\/span><\/span>\u00a0\u00e9\u00a0<\/b><\/span><\/span>usada h\u00e1 anos para rastrear gado, vag\u00f5es de trem, bagagem a\u00e9rea e carros nos ped\u00e1gios.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Um modelo mais barato dessas etiquetas\u00a0<\/b><\/span><\/span>pode funcionar sem baterias e \u00e9 constitu\u00eddo por tr\u00eas componentes: um microprocessador de sil\u00edcio; uma bobina de metal, feita de cobre ou de alum\u00ednio, que \u00e9 enrolada em um padr\u00e3o circular; e um encapsulador, que \u00e9 um material de vidro ou pol\u00edmero envolvendo o microprocessador e a bobina.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span><\/span><\/span><\/p>\n

Na\u00a0<\/b><\/span><\/span>presen\u00e7a de um campo de radiofrequ\u00eancia gerado pelo leitor, a etiqueta transmite sinais.<\/b><\/span><\/span><\/span><\/span><\/p>\n

A\u00a0<\/b><\/span><\/span>dist\u00e2ncia de leitura \u00e9 determinada pelo tamanho da bobina e pela pot\u00eancia da onda de r\u00e1dio emitida pelo leitor<\/b><\/span><\/span>.<\/b><\/span><\/span><\/span><\/span><\/p>\n

A\u00a0<\/b><\/span><\/span>etiqueta funciona sem pilhas porque o campo
\n(A)\u00a0<\/b><\/span><\/span>el\u00e9trico da onda de r\u00e1dio agita el\u00e9trons da bobina.
\n<\/b><\/span><\/span>(B)\u00a0<\/b><\/span><\/span>el\u00e9trico da onda de r\u00e1dio cria uma tens\u00e3o na bobina.
\n<\/b><\/span><\/span>(C)\u00a0<\/b><\/span><\/span>magn\u00e9tico da onda de r\u00e1dio induz corrente na bobina.
\n<\/b><\/span><\/span>(D)\u00a0<\/b><\/span><\/span>magn\u00e9tico da onda de r\u00e1dio aquece os fios da bobina.
\n<\/b><\/span><\/span>(E)\u00a0<\/b><\/span><\/span>magn\u00e9tico da onda de r\u00e1dio diminui a resson\u00e2ncia no interior da bobina<\/b><\/span><\/span>.<\/b><\/span><\/span><\/span><\/span><\/p>\n

 <\/p>\n

22- Escola Naval 2018\/2019<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

Analise a figura abaixo.<\/b><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

A figura acima mostra uma espira retangular, de\u00a0<\/b><\/span><\/span>lados a=40 cm e b=20 cm,<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>no instante t=0.\u00a0<\/b><\/span><\/span>Considere que\u00a0<\/b><\/span><\/span>a espira se move com velocidade v=5,0 cm\/s, para a esquerda,<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>perpendicularmente a um campo magn\u00e9tico uniforme de indu\u00e7\u00e3o, B=2,0 T.\u00a0<\/b><\/span><\/span>Sabendo que\u00a0<\/b><\/span><\/span>a espira tem uma resist\u00eancia de 20 \u03a9, qual \u00e9 a intensidade, em amp\u00e8re, da corrente el\u00e9trica na espira em t=3,0 s?<\/b><\/span><\/span><\/span><\/span><\/p>\n

(A) 1,0.10-3<\/b><\/span><\/span><\/span><\/span><\/p>\n

(B) 2,0.10-3<\/b><\/span><\/span><\/span><\/span><\/p>\n

(C) 3,0.10-3<\/b><\/span><\/span><\/span><\/span><\/p>\n

(D) 1,0.10-2<\/b><\/span><\/span><\/span><\/span><\/p>\n

(E) 2,0.10-2<\/b><\/span><\/span><\/span><\/span><\/p>\n

 <\/p>\n

23- (ITA \u2013 SP \u2013 019)<\/b><\/span><\/span><\/span><\/em>\u00a0<\/b><\/i><\/span><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n


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

<\/p>\n

<\/p>\n

 <\/p>\n

24- (UDESC-SC-019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

A\u00a0<\/b><\/span><\/span>figura mostra um circuito colocado acima de um \u00edm\u00e3<\/b><\/span><\/span>, cujo\u00a0<\/b><\/span><\/span>campo magn\u00e9tico \u00e9 restringido pela \u00e1rea cinza,<\/b><\/span><\/span>\u00a0e as\u00a0<\/b><\/span><\/span>linhas de campo magn\u00e9tico s\u00e3o perpendiculares em rela\u00e7\u00e3o ao plano do circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

Analise as proposi\u00e7\u00f5es em rela\u00e7\u00e3o \u00e0 figura<\/b><\/span><\/span>.<\/b><\/span><\/span><\/span><\/span><\/p>\n

I.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Ao\u00a0<\/b><\/span><\/span>deslocarmos o circuito e o \u00edm\u00e3 juntos em sentidos contr\u00e1rios,\u00a0<\/b><\/span><\/span>ao\u00a0<\/b><\/span><\/span>longo da dire\u00e7\u00e3o y, surge corrente no circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

II.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Ao\u00a0<\/b><\/span><\/span>deslocarmos somente o \u00edm\u00e3, ao longo da dire\u00e7\u00e3o x, observa-se corrente no circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

III.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Se o\u00a0<\/b><\/span><\/span>campo magn\u00e9tico variar no tempo, surge corrente no circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

IV.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Ao\u00a0<\/b><\/span><\/span>deslocar-se o circuito e o \u00edm\u00e3 juntos no mesmo sentido e na mesma velocidade, ao longo da dire\u00e7\u00e3o y, observa-se corrente no circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

V.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>Ao\u00a0<\/b><\/span><\/span>deslocar-se o circuito e o \u00edm\u00e3 juntos no mesmo sentido e na mesma velocidade, ao longo da dire\u00e7\u00e3o x, surge corrente no circuito.<\/b><\/span><\/span><\/span><\/span><\/p>\n

Assinale a\u00a0<\/b><\/span><\/span>alternativa\u00a0correta.<\/b><\/span><\/span><\/span><\/span><\/p>\n

A.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>( ) Somente as afirmativas I, II e IV s\u00e3o verdadeiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

B.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>( ) Somente as afirmativas I, III e V s\u00e3o verdadeiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

C.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>( ) Somente as afirmativas I, II e III s\u00e3o verdadeiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

D.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>( ) Somente as afirmativas II, IV e V s\u00e3o verdadeiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

E.<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>( ) Somente as afirmativas III, IV e V s\u00e3o verdadeiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

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25- (UERR-RR-019)<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

<\/p>\n

Num\u00a0<\/b><\/span><\/span>sistema formado por uma bobina de fio de cobre conectada a um amper\u00edmetro<\/b><\/span><\/span>\u00a0e\u00a0<\/b><\/span><\/span>um \u00edm\u00e3,<\/b><\/span><\/span>\u00a0se\u00a0<\/b><\/span><\/span>neste se detecta corrente el\u00e9trica significa\u00a0<\/b><\/span><\/span>que:<\/b><\/span><\/span><\/span><\/span><\/p>\n

A)\u00a0<\/b><\/span><\/span>o \u00edm\u00e3 est\u00e1 colocado no interior da bobina completamente.<\/b><\/span><\/span><\/span><\/span><\/p>\n

B)\u00a0<\/b><\/span><\/span>o \u00edm\u00e3 est\u00e1 totalmente afastado da bobina.<\/b><\/span><\/span><\/span><\/span><\/p>\n

C)\u00a0<\/b><\/span><\/span>a bobina foi constru\u00edda com uma quantidade muito grande de espiras.<\/b><\/span><\/span><\/span><\/span><\/p>\n

D)\u00a0<\/b><\/span><\/span>o \u00edm\u00e3 est\u00e1 colocado fora da bobina, mas paralelo a esta.<\/b><\/span><\/span><\/span><\/span><\/p>\n

E)\u00a0<\/b><\/span><\/span>o \u00edm\u00e3 est\u00e1 movendo-se continuamente em rela\u00e7\u00e3o \u00e0 bobina.<\/b><\/span><\/span><\/span><\/span><\/p>\n

26-(ENEM-MEC-017)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Para\u00a0<\/b><\/span><\/span><\/span>demonstrar o processo de transforma\u00e7\u00e3o de energia mec\u00e2nica em el\u00e9trica,\u00a0<\/b><\/span><\/span><\/span>um\u00a0<\/b><\/span><\/span><\/span>estudante constr\u00f3i um pequeno gerador utilizando:<\/b><\/span><\/span><\/span><\/p>\n

\u00a0um\u00a0<\/b><\/span><\/span><\/span>fio de cobre de di\u00e2metro D enrolado em N espiras circulares de \u00e1rea A;<\/b><\/span><\/span><\/span><\/p>\n

\u00a0dois\u00a0<\/b><\/span><\/span><\/span>\u00edm\u00e3s que criam no espa\u00e7o entre eles um campo magn\u00e9tico uniforme de intensidade B;\u00a0<\/b><\/span><\/span><\/span>e<\/b><\/span><\/span><\/span><\/p>\n

\u00a0um\u00a0<\/b><\/span><\/span><\/span>sistema de engrenagens\u00a0<\/b><\/span><\/span><\/span>que lhe permite\u00a0<\/b><\/span><\/span><\/span>girar as espiras em torno de um eixo\u00a0<\/b><\/span><\/span><\/span>com uma\u00a0<\/b><\/span><\/span><\/span>frequ\u00eancia f.<\/b><\/span><\/span><\/span><\/p>\n

Ao\u00a0<\/b><\/span><\/span><\/span>fazer<\/b><\/span><\/span><\/span>\u00a0o\u00a0<\/b><\/span><\/span><\/span>gerador funcionar,<\/b><\/span><\/span><\/span>\u00a0o\u00a0<\/b><\/span><\/span><\/span>estudante obteve uma tens\u00e3o m\u00e1xima V\u00a0<\/b><\/span><\/span><\/span>e uma\u00a0<\/b><\/span><\/span><\/span>corrente de curto-circuito i.<\/b><\/span><\/span><\/span><\/p>\n

Para dobrar o valor da tens\u00e3o m\u00e1xima V do gerador mantendo constante o valor da corrente de curto i, o estudante deve dobrar o(a)<\/b><\/span><\/span><\/span><\/p>\n

(a)\u00a0<\/b><\/span><\/span><\/span>n\u00famero de espiras.<\/b><\/span><\/span><\/span><\/p>\n

(b)\u00a0<\/b><\/span><\/span><\/span>frequ\u00eancia de giro.<\/b><\/span><\/span><\/span><\/p>\n

(c)\u00a0<\/b><\/span><\/span><\/span>intensidade do campo magn\u00e9tico.<\/b><\/span><\/span><\/span><\/p>\n

(d)\u00a0<\/b><\/span><\/span><\/span>\u00e1rea das espiras.<\/b><\/span><\/span><\/span><\/p>\n

(e)\u00a0<\/b><\/span><\/span><\/span>di\u00e2metro do fio.<\/b><\/span><\/span><\/span><\/p>\n

27- (Faculdade de Ci\u00eancias M\u00e9dicas da Santa Casa de S\u00e3o Paulo \u2013 018)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

<\/p>\n

<\/p>\n

28- (ESCOLA NAVAL \u2013 2017\/2018)<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Analise<\/b><\/span><\/span><\/span>\u00a0a\u00a0<\/b><\/span><\/span><\/span>figura abaixo.\u00a0<\/b><\/span><\/span><\/span><\/p>\n

\"ELETROMAGNETISMO\"<\/p>\n

 <\/p>\n

Confira a resolu\u00e7\u00e3o comentada<\/strong><\/a><\/span>\u00a0 \u00a0<\/span><\/h3>\n

 <\/p>\n

Clique aqui para ver sobre o tema!<\/a><\/p>\n

Confira as v\u00eddeo aulas!<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

ELETROMAGNETISMO \u2013 2018\/2019 Im\u00e3s, Campo Magn\u00e9tico e For\u00e7a Magn\u00e9tica 01- (URCA-CE-019) A)Em ambos os casos podemos rejuntar os peda\u00e7os conforme as posi\u00e7\u00f5es que est\u00e3o. B)\u00a0Somente no corte longitudinal podem-se rejuntar os peda\u00e7os, C)\u00a0N\u00e3o tem como rejuntar os peda\u00e7os do corte transversal porque provem do mesmo \u00edm\u00e3. D)Somente os cortes transversais podem rejuntar. E)\u00a0Ambos podem se rejuntar, por\u00e9m, o corte transversal<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":3299,"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-4854","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4854","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=4854"}],"version-history":[{"count":4,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4854\/revisions"}],"predecessor-version":[{"id":9913,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4854\/revisions\/9913"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/3299"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=4854"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}