{"id":4513,"date":"2019-07-01T02:09:00","date_gmt":"2019-07-01T02:09:00","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=4513"},"modified":"2024-07-11T11:41:05","modified_gmt":"2024-07-11T11:41:05","slug":"cederj-2019","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/universidades-2019\/cederj-2019\/","title":{"rendered":"CEDERJ 2019"},"content":{"rendered":"

CEDERJ-RJ-2019<\/b><\/span><\/span><\/span><\/p>\n

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(CEDERJ-RJ)\u00a0\u2013\u00a0Centro de Ci\u00eancias e Educa\u00e7\u00e3o Superior a Dist\u00e2ncia do Estado do Rio de Janeiro<\/b><\/span><\/span><\/span><\/p>\n

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

Contribuir para a interioriza\u00e7\u00e3o do ensino superior p\u00fablico, gratuito e de qualidade no Estado do Rio de Janeiro por meio da oferta de cursos de gradua\u00e7\u00e3o a dist\u00e2ncia, na modalidade semipresencial, garantindo a qualidade destes no que diz respeito ao processo de avalia\u00e7\u00e3o de aprendizagem.<\/b><\/span><\/span><\/span><\/p>\n

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01 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Dois corpos pontuais portando cargas respectivamente iguais a Q e Q\u2019 est\u00e3o em repouso <\/b><\/span><\/span>conectados <\/b><\/span><\/span>por uma mola<\/b><\/span><\/span>. Quando a <\/b><\/span><\/span>carga de um deles \u00e9 dobrada, passando de Q para 2Q,<\/b><\/span><\/span> a<\/b><\/span><\/span><\/p>\n

<\/p>\n

extens\u00e3o da mola diminui na nova posi\u00e7\u00e3o de equil\u00edbrio.<\/b><\/span><\/span> <\/b>Quatro hip\u00f3teses foram elaboradas sobre os sinais das cargas:<\/b><\/span><\/span><\/p>\n

I: <\/b><\/span><\/span>Q > 0 e Q\u2019 > 0 <\/b><\/span><\/span>II: <\/b><\/span><\/span>Q > 0 e Q\u2019 < 0 <\/b><\/span><\/span>III: <\/b><\/span><\/span>Q < 0 e Q\u2019 > 0 <\/b><\/span><\/span>IV: <\/b><\/span><\/span>Q < 0 e Q\u2019 < 0<\/b><\/span><\/span><\/p>\n

S\u00e3o <\/b><\/span><\/span>compat\u00edveis com o fen\u00f4meno descrito as hip\u00f3teses<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>I e IV <\/b><\/span><\/span>(B) <\/b><\/span><\/span>III e IV <\/b><\/span><\/span>(C) <\/b><\/span><\/span>II e III <\/b><\/span><\/span>(D) <\/b><\/span><\/span>I e III<\/b><\/span><\/span><\/p>\n

02 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Duas amostras de g\u00e1s est\u00e3o em um recipiente r\u00edgido isolado termicamente do exterior e com duas c\u00e2maras separadas por uma parede que tamb\u00e9m \u00e9 r\u00edgida.<\/b><\/span><\/span> O <\/b><\/span><\/span>g\u00e1s na primeira c\u00e2mara <\/b><\/span><\/span>est\u00e1 a<\/b><\/span><\/span><\/p>\n

<\/p>\n

uma <\/b><\/span><\/span>temperatura menor que o g\u00e1s na segunda c\u00e2mara.<\/b><\/span><\/span> Lentamente, a <\/b><\/span><\/span>parede r\u00edgida permite a passagem de calor levando a uma situa\u00e7\u00e3o de equil\u00edbrio t\u00e9rmico entre as c\u00e2maras. <\/b><\/span><\/span>A <\/b><\/span><\/span>varia\u00e7\u00e3o de energia interna do g\u00e1s na primeira c\u00e2mara, \u0394U, e o calor recebido por ele, Q, t\u00eam seus sinais descritos por<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>\u0394U > 0 e Q > 0 <\/b><\/span><\/span>(B) <\/b><\/span><\/span>\u0394U > 0 e Q < 0 <\/b><\/span><\/span>(C) <\/b><\/span><\/span>\u0394U < 0 e Q > 0 <\/b><\/span><\/span>(D) <\/b><\/span><\/span>\u0394U < 0 e Q < 0<\/b><\/span><\/span><\/p>\n

03 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Um <\/b><\/span><\/span>homem de 80 kg equilibra-se sobre uma plataforma horizontal,<\/b><\/span><\/span> de <\/b><\/span><\/span>massa desprez\u00edvel, com 8 metros de extens\u00e3o. <\/b><\/span><\/span>A <\/b><\/span><\/span>plataforma tem suas extremidades apoiadas em duas balan\u00e7as. <\/b><\/span><\/span><\/p>\n

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Originalmente, <\/b><\/span><\/span>ambas marcam 40 kg em suas leituras. <\/b><\/span><\/span>O <\/b><\/span><\/span>homem aproxima-se de uma das<\/b><\/span><\/span><\/p>\n

extremidades e as leituras nas balan\u00e7as passam a ser de 60 kg e 20 kg.<\/b><\/span><\/span> O <\/b><\/span><\/span>deslocamento do homem foi de<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>0,5 m <\/b><\/span><\/span>(B) <\/b><\/span><\/span>1,0 m <\/b><\/span><\/span>(C) <\/b><\/span><\/span>1,5 m <\/b><\/span><\/span>(D) <\/b><\/span><\/span>2,0 m<\/b><\/span><\/span><\/p>\n

04 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Uma <\/b><\/span><\/span>crian\u00e7a com 20 kg oscila <\/b><\/span><\/span>num <\/b><\/span><\/span>balan\u00e7o, de tal modo que a diferen\u00e7a entre as alturas m\u00e1xima e m\u00ednima que ela atinge \u00e9 de 0,80 m. <\/b><\/span><\/span>Na <\/b><\/span><\/span>posi\u00e7\u00e3o de m\u00e1xima altura<\/b><\/span><\/span>, a <\/b><\/span><\/span>crian\u00e7a apresenta uma energia<\/b><\/span><\/span><\/p>\n

<\/p>\n

potencial 160 J maior que a da posi\u00e7\u00e3o de m\u00ednima altura.<\/b><\/span><\/span> <\/b><\/p>\n

A <\/b><\/span><\/span>velocidade da crian\u00e7a, quando ela passa pela posi\u00e7\u00e3o de menor altura,<\/b><\/span><\/span> ser\u00e1 de<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>3 m\/s <\/b><\/span><\/span>(B) <\/b><\/span><\/span>4 m\/s <\/b><\/span><\/span>(C) <\/b><\/span><\/span>5 m\/s <\/b><\/span><\/span>(D) <\/b><\/span><\/span>6 m\/s<\/b><\/span><\/span><\/p>\n

05 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Um <\/b><\/span><\/span>aqu\u00e1rio cont\u00e9m uma quantidade fixa de \u00e1gua <\/b><\/span><\/span>e a <\/b><\/span><\/span>press\u00e3o que ela exerce no fundo do mesmo \u00e9 P<\/b><\/span><\/span>. <\/b><\/span><\/span>Alternadamente, dois objetos distintos, de mesmo volume,<\/b><\/span><\/span> por\u00e9m de <\/b><\/span><\/span>massas distintas<\/b><\/span><\/span>, s\u00e3o<\/b><\/span><\/span><\/p>\n

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colocados dentro do aqu\u00e1rio sem derramar \u00e1gu<\/b><\/span><\/span>a. O <\/b><\/span><\/span>primeiro objeto flutua na \u00e1gua, com apenas<\/b><\/span><\/span><\/p>\n

uma parte do seu volume submerso<\/b><\/span><\/span>. Entretanto, quando <\/b><\/span><\/span>o segundo objeto \u00e9 inserido, ele submerge completamente.<\/b><\/span><\/span><\/p>\n

As <\/span>respectivas press\u00f5es exercidas pela \u00e1gua no fundo do aqu\u00e1rio em cada um dos casos s\u00e3o denotadas por P<\/span><\/span>1<\/span><\/sub><\/span> e P<\/span><\/span>2<\/span><\/sub><\/span>.<\/span><\/span><\/h1>\n

As <\/b><\/span><\/span>compara\u00e7\u00f5es entre P<\/b><\/span><\/span>1<\/b><\/span><\/sub><\/span> , P<\/b><\/span><\/span>2<\/b><\/span><\/sub><\/span> e P<\/b><\/span><\/span> s\u00e3o:<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span><\/span>P<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> > P<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> > <\/b><\/span><\/span><\/span>P <\/b><\/span><\/span><\/span>(B) <\/b><\/span><\/span><\/span>P<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> > P<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> > P <\/b><\/span><\/span><\/span>(C) <\/b><\/span><\/span><\/span>P > P<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> > P<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>(D) <\/b><\/span><\/span><\/span>P > P<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> > P<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span><\/p>\n

06 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Dois m\u00f3veis executam curvas semicirculares,<\/b><\/span><\/span> mantendo os <\/b><\/span><\/span>m\u00f3dulos de suas velocidades constantes<\/b><\/span><\/span>. Os <\/b><\/span><\/span>raios das curvas s\u00e3o distintos, por\u00e9m o tempo que cada m\u00f3vel gasta para execut\u00e1-las \u00e9 o mesmo.<\/b><\/span><\/span> Considerando que o <\/b><\/span><\/span>raio da curva efetuada pelo m\u00f3vel 1 \u00e9 o dobro do raio da<\/b><\/span><\/span><\/p>\n

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curva efetuada pelo m\u00f3vel 2<\/b><\/span><\/span>, a <\/b><\/span><\/span>rela\u00e7\u00e3o entre as intensidades das for\u00e7as centr\u00edpetas F<\/b><\/span><\/span>1<\/b><\/span><\/sub><\/span> e F<\/b><\/span><\/span>2<\/b><\/span><\/sub><\/span> que atuam, respectivamente, sobre os m\u00f3veis 1 e 2 \u00e9:<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span><\/span>F<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = F<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>(B) <\/b><\/span><\/span><\/span>F<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = F<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>(C) <\/b><\/span><\/span><\/span>F<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 2F<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>(D)<\/b><\/span><\/span><\/span> <\/b>F<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 4F<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span><\/p>\n

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

07 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Um <\/b><\/span><\/span>autom\u00f3vel, trafegando em linha reta <\/b><\/span><\/span>com <\/b><\/span><\/span>acelera\u00e7\u00e3o constante, aumenta a sua velocidade de<\/b><\/span><\/span><\/p>\n

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10 m\/s para 20 m\/s em 20 s<\/b><\/span><\/span>. A <\/b><\/span><\/span>dist\u00e2ncia percorrida pelo autom\u00f3vel durante esses 20 s<\/b><\/span><\/span> foi de:<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>200 m <\/b><\/span><\/span>(B) <\/b><\/span><\/span>300 m <\/b><\/span><\/span>(C) <\/b><\/span><\/span>400 <\/b><\/span><\/span>m <\/b><\/span><\/span>(D) <\/b><\/span><\/span>600 m<\/b><\/span><\/span><\/p>\n

08 \u2013 (CEDERJ-RJ-2019)<\/b><\/span><\/span><\/span><\/p>\n

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Uma <\/b><\/span><\/span>bolinha \u00e9 arremessada horizontalmente em dire\u00e7\u00e3o ao rodap\u00e9 de uma parede <\/b><\/span><\/span>com uma<\/b><\/span><\/span><\/p>\n

<\/a> <\/p>\n

quantidade de movimento <\/b><\/span><\/span>p <\/b><\/span><\/span>= m<\/b><\/span><\/span>v<\/b><\/span><\/span>,<\/b><\/span><\/span> onde <\/b><\/span><\/span>m e <\/b><\/span><\/span>v <\/b><\/span><\/span>representam, <\/b><\/span><\/span>respectivamente<\/b><\/span><\/span>, a <\/b><\/span><\/span>massa e o vetor velocidade da bolinha. <\/b><\/span><\/span>Ela <\/b><\/span><\/span>colide com o rodap\u00e9 e retorna com uma quantidade de movimento<\/b><\/span><\/span><\/p>\n

P <\/b><\/span><\/span>= –<\/b><\/span><\/span>p<\/b><\/span><\/span>\/2. <\/b><\/span><\/span>O <\/b><\/span><\/span>impulso que o rodap\u00e9 exerce sobre a bolinha <\/b><\/span><\/span>\u00e9:<\/b><\/span><\/span><\/p>\n

(A) <\/b><\/span><\/span>-3<\/b><\/span><\/span>p<\/b><\/span><\/span>\/2<\/b><\/span><\/span> <\/b>(B) <\/b><\/span><\/span>+3<\/b><\/span><\/span>p<\/b><\/span><\/span>\/2 <\/b><\/span><\/span>(C) <\/b><\/span><\/span>–<\/b><\/span><\/span>p<\/b><\/span><\/span>\/2 <\/b><\/span><\/span>(D) <\/b><\/span><\/span>+<\/b><\/span><\/span>p<\/b><\/span><\/span>\/2<\/b><\/span><\/span><\/p>\n

Resolu\u00e7\u00e3o comentada das quest\u00f5es de F\u00edsica da CEDERJ-RJ)\u00a0\u2013\u00a0Centro de Ci\u00eancias e Educa\u00e7\u00e3o Superior a Dist\u00e2ncia do Estado do Rio de Janeiro<\/b><\/span><\/span><\/span><\/span><\/span><\/p>\n

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

As\u00a0<\/b><\/span><\/span><\/span>cargas do el\u00e9tron e do pr\u00f3ton s\u00e3o opostas e convencionou-se atribuir ao el\u00e9tron carga negativa e ao pr\u00f3ton, carga positiva.<\/b><\/span><\/span><\/span><\/p>\n

Cargas de mesmo sinal se repelem<\/b><\/span><\/span> e <\/b><\/span><\/span>cargas de sinais opostos se atraem pela for\u00e7a <\/b><\/span><\/span>calculada na express\u00e3o abaixo:<\/b><\/span><\/span><\/p>\n

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A <\/b><\/span><\/span>for\u00e7a entre elas \u00e9 diretamente proporcional ao m\u00f3dulo das cargas <\/b><\/span><\/span>e, como <\/b><\/span><\/span>Q dobra a for\u00e7a entre<\/b><\/span><\/span><\/p>\n

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elas tamb\u00e9m deve dobrar <\/b><\/span><\/span>e, se o <\/b><\/span><\/span>comprimento da mola diminui, essa for\u00e7a s\u00f3 pode ser de atra\u00e7\u00e3o com as cargas possuindo sinais opostos<\/b><\/span><\/span> (uma positiva e a outra negativa)<\/b><\/span><\/span><\/p>\n

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

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

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

Quando dois ou mais corpos que est\u00e3o a\u00a0<\/b><\/span><\/span>temperaturas diferentes s\u00e3o colocados em contato,\u00a0<\/b><\/span><\/span>ocorrer\u00e1 uma\u00a0<\/b><\/span><\/span>transfer\u00eancia de energia do corpo de maior temperatura para o corpo de menor temperatura.<\/b><\/span><\/span><\/p>\n

Essa\u00a0<\/b><\/span><\/span>transfer\u00eancia de energia ocorre at\u00e9 que os dois corpos tenham a mesma temperatura (mesmo<\/b><\/span><\/span><\/p>\n

estado t\u00e9rmico,\u00a0<\/b><\/span><\/span>mesmo n\u00edvel de vibra\u00e7\u00e3o das mol\u00e9culas), estejam numa situa\u00e7\u00e3o de equil\u00edbrio.<\/b><\/span><\/span><\/p>\n

Essa\u00a0transfer\u00eancia de energia\u00a0recebe o nome de\u00a0calor<\/b><\/span><\/span>.<\/b><\/span><\/span><\/p>\n

Ent\u00e3o o <\/b><\/span><\/span>g\u00e1s que est\u00e1 na primeira c\u00e2mara <\/b><\/span><\/span>(menor temperatura) <\/b><\/span><\/span>recebe calor da outra de maior<\/b><\/span><\/span><\/p>\n

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temperatura <\/b><\/span><\/span>(Q > 0) e sua <\/b><\/span><\/span>energia interna aumenta porque sua varia\u00e7\u00e3o de temperatura tamb\u00e9m aumenta<\/b><\/span><\/span> (<\/b><\/span><\/span>\u0394U<\/b><\/span><\/span><\/span> > 0).<\/b><\/span><\/span><\/p>\n

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

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

Inicialmente as balan\u00e7as marcam o mesmo valor 40 kg <\/b><\/span><\/span>que \u00e9 <\/b><\/span><\/span>igual \u00e0 metade da massa do homem.<\/b><\/span><\/span> Isso significa que <\/b><\/span><\/span>ele est\u00e1 na metade da plataforma, equidistante 4 m de cada extremidade.<\/b><\/span><\/span><\/p>\n

Situa\u00e7\u00e3o depois <\/b><\/span><\/span> quando ele <\/b><\/span><\/span>se aproxima de uma das extremidades<\/b><\/span><\/span>, por exemplo, a <\/b><\/span><\/span>da direita, as balan\u00e7as passam a marcar 20 kg (P<\/b><\/span><\/span>e<\/b><\/span><\/sub><\/span> = 20.10 = 200 N) a da esquerda e 60 kg (P<\/b><\/span><\/span>d<\/b><\/span><\/sub><\/span> = 60.10 = 600 N) a da direita.<\/b><\/span><\/span><\/p>\n

Colocando o <\/b><\/span><\/span>polo O na balan\u00e7a da esquerda, <\/b><\/span><\/span>calculando<\/b><\/span><\/span> m\u00f3dulo do momento de cada for\u00e7a em rela\u00e7\u00e3o ao mesmo e estabelecendo o sentido hor\u00e1rio de rota\u00e7\u00e3o como positivo:<\/b><\/span><\/span><\/p>\n

<\/p>\n

<\/p>\n

Ent\u00e3o, <\/b><\/span><\/span>ao se deslocar ele passou da posi\u00e7\u00e3o 4 m <\/b><\/span><\/span>(antes) <\/b><\/span><\/span>para a posi\u00e7\u00e3o 6 m<\/b><\/span><\/span> (depois), se <\/b><\/span><\/span>deslocando <\/b><\/span><\/span><\/p>\n

S =<\/b><\/span><\/span> 6 \u2013 4 <\/b><\/span><\/span>= 2m<\/b><\/span><\/span><\/p>\n

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

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

Na <\/b><\/span><\/span>posi\u00e7\u00e3o de altura m\u00e1xima onde a velocidade \u00e9 nula<\/b><\/span><\/span> a <\/b><\/span><\/span>energia cin\u00e9tica tamb\u00e9m \u00e9 nula <\/b><\/span><\/span>e <\/b><\/span><\/span>a energia potencial vale 160 J<\/b><\/span><\/span>. Nessa posi\u00e7\u00e3o a <\/b><\/span><\/span>energia total (mec\u00e2nica) que \u00e9 a soma das duas vale E<\/b><\/span><\/span>M<\/b><\/span><\/sub><\/span> = 160 J. <\/b><\/span><\/span><\/p>\n

No <\/b><\/span><\/span>ponto de altura m\u00ednima (h = 0) a energia potencial \u00e9 nula <\/b><\/span><\/span>e a <\/b><\/span><\/span>energia cin\u00e9tica \u00e9 a mec\u00e2nica que vale E<\/b><\/span><\/span>m<\/b><\/span><\/sub><\/span> = 160 J <\/b><\/span><\/span>(princ\u00edpio da conserva\u00e7\u00e3o da energia mec\u00e2nica). <\/b><\/span><\/span><\/p>\n

<\/p>\n

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

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

Teorema Fundamental da Hidrost\u00e1tica ou Teorema de Stevin<\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Observe <\/b><\/span><\/span><\/span>pelo teorema de Stevin que quanto maior a altura h da coluna l\u00edquida <\/b><\/span><\/span><\/span>(no caso do fundo do aqu\u00e1rio), <\/b><\/span><\/span><\/span>maior ser\u00e1 a press\u00e3o devido a \u00e1gua nesse ponto. <\/b><\/span><\/span><\/span><\/p>\n

<\/p>\n

Assim, <\/b><\/span><\/span>h<\/b><\/span><\/span>2<\/b><\/span><\/sub><\/span> > h<\/b><\/span><\/span>1<\/b><\/span><\/sub><\/span> > h (veja figuras acima)<\/b><\/span><\/span><\/p>\n

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

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

Os\u00a0<\/b><\/span><\/span>dois carros A e B\u00a0da figura mant\u00eam-se\u00a0lado a lado\u00a0numa pista\u00a0circular<\/b><\/span><\/span>, <\/b><\/span><\/span>no mesmo intervalo de tempo\u00a0\u0394t.<\/b><\/span><\/span><\/p>\n

<\/p>\n

Seus\u00a0raios\u00a0nesse\u00a0MCU\u00a0s\u00e3o, respectivamente,\u00a0R<\/b><\/span><\/span>A<\/b><\/span><\/sub><\/span>\u00a0e R<\/b><\/span><\/span>B<\/b><\/span><\/sub><\/span>, com R<\/b><\/span><\/span>B<\/b><\/span><\/sub><\/span>\u00a0> R<\/b><\/span><\/span>A<\/b><\/span><\/sub><\/span>.<\/b><\/span><\/span><\/p>\n

O\u00a0<\/b><\/span><\/span>carro B<\/b><\/span><\/span>\u00a0<\/b><\/span><\/span>ter\u00e1\u00a0maior velocidade (escalar, linear) V=\u0394S\/\u0394t, pois dever\u00e1\u00a0percorrer\u00a0maior dist\u00e2ncia \u0394S\u00a0para, no mesmo intervalo de tempo, poder acompanhar o carro A, ou seja, V<\/b><\/span><\/span>A<\/b><\/span><\/sub><\/span>\u00a0> V<\/b><\/span><\/span>B<\/b><\/span><\/sub><\/span>.\u00a0\u00a0<\/b><\/span><\/span>Mas, como <\/b><\/span><\/span>\u201c<\/b><\/span><\/span>varrem\u201d o mesmo \u00e2ngulo (\u0394\u03c6) no mesmo intervalo de tempo<\/b><\/span><\/span>, <\/b><\/span><\/span>suas <\/b><\/span><\/span>velocidades angulares (W= \u0394\u03c6\/\u0394t) ser\u00e3o iguais, ou seja,\u00a0W<\/b><\/span><\/span>A <\/b><\/span><\/sub><\/span>= W<\/b><\/span><\/span>B<\/b><\/span><\/sub><\/span>.<\/b><\/span><\/span><\/p>\n

\"CEDERJ\"<\/p>\n

A <\/b><\/span><\/span>velocidade angular W \u00e9 a mesma para os dois carros <\/b><\/span><\/span>(veja teoria acima) e como a <\/b><\/span><\/span>intensidade da for\u00e7a centr\u00edpeta sobre cada um \u00e9 fornecida por F<\/b><\/span><\/span>c<\/b><\/span><\/sub><\/span> = m.W<\/b><\/span><\/span>2<\/b><\/span><\/sup><\/span>.R,<\/b><\/span><\/span> essa express\u00e3o indica <\/b><\/span><\/span>que F<\/b><\/span><\/span>c<\/b><\/span><\/sub><\/span> \u00e9 diretamente proporcional ao raio R. <\/b><\/span><\/span> <\/b><\/p>\n

Ent\u00e3o, se voc\u00ea <\/b><\/span><\/span>dobrar R estar\u00e1 dobrando F<\/b><\/span><\/span>c<\/b><\/span><\/sub><\/span> (desde que as massas sejam as mesmas).<\/b><\/span><\/span><\/p>\n

R \u2013 C<\/b><\/span><\/span><\/span><\/p>\n

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

S\u00e3o dados:<\/b><\/span><\/span> <\/b>V<\/b><\/span><\/span>o<\/b><\/span><\/sub><\/span> = <\/b><\/span><\/span>10 m\/s; <\/b><\/span><\/span>V = <\/b><\/span><\/span>20 m\/s e <\/b><\/span><\/span>t = <\/b><\/span><\/span>20 s.<\/b><\/span><\/span><\/p>\n

Equa\u00e7\u00e3o da velocidade do MUV <\/b><\/span><\/span> <\/b>V = V<\/b><\/span><\/span>o<\/b><\/span><\/sub><\/span> + a.t <\/b><\/span><\/span>20 = 10 + a.20 a = 10\/20 a = 0,5 m\/s<\/b><\/span><\/span>2<\/b><\/span><\/sup><\/span>. (acelera\u00e7\u00e3o do movimento que \u00e9 constante)<\/b><\/span><\/span><\/p>\n

Equa\u00e7\u00e3o hor\u00e1ria do espa\u00e7o do MUV<\/b><\/span><\/span> <\/b>\u2206S = V<\/b><\/span><\/span>o<\/b><\/span><\/sub><\/span>.t + a.t<\/b><\/span><\/span>2<\/b><\/span><\/sup><\/span>\/2 <\/b><\/span><\/span>= 10.20 + 0,5.20<\/b><\/span><\/span>2<\/b><\/span><\/sup><\/span>\/2 = 200 + 0,5.200 <\/b><\/span><\/span><\/p>\n

\u2206S = 300 m <\/b><\/span><\/span><\/p>\n

R \u2013 B<\/b><\/span><\/span><\/span><\/p>\n

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

Teorema do Impulso <\/b><\/span><\/span>\u201co impulso de uma for\u00e7a \u00e9 igual \u00e0 varia\u00e7\u00e3o da quantidade de movimento\u201d.<\/b><\/span><\/span><\/p>\n

<\/p>\n

R- A<\/b><\/span><\/span><\/span><\/p>\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":"

CEDERJ-RJ-2019 (CEDERJ-RJ)\u00a0\u2013\u00a0Centro de Ci\u00eancias e Educa\u00e7\u00e3o Superior a Dist\u00e2ncia do Estado do Rio de Janeiro Objetivo: Contribuir para a interioriza\u00e7\u00e3o do ensino superior p\u00fablico, gratuito e de qualidade no Estado do Rio de Janeiro por meio da oferta de cursos de gradua\u00e7\u00e3o a dist\u00e2ncia, na modalidade semipresencial, garantindo a qualidade destes no que diz respeito ao processo de avalia\u00e7\u00e3o de<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":4337,"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-4513","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4513","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=4513"}],"version-history":[{"count":3,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4513\/revisions"}],"predecessor-version":[{"id":10286,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4513\/revisions\/10286"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/4337"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=4513"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}