{"id":910,"date":"2015-06-29T00:14:14","date_gmt":"2015-06-29T00:14:14","guid":{"rendered":"http:\/\/fisicaevestibular.com.br\/novo\/?page_id=910"},"modified":"2024-09-02T17:41:31","modified_gmt":"2024-09-02T17:41:31","slug":"resolucao-comentada-da-uema-2015","status":"publish","type":"page","link":"https:\/\/fisicaevestibular.com.br\/novo\/universidades-2015\/exercicios-resolvidos-da-uema-2015\/resolucao-comentada-da-uema-2015\/","title":{"rendered":"Resolu\u00e7\u00e3o comentada da UEMA 2015"},"content":{"rendered":"

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

01- <\/b><\/span><\/span><\/span>Homens \"\" V<\/b><\/span><\/span><\/span>mh<\/b><\/span><\/span><\/sub><\/span> = \u2206S\/\u2206t<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>V<\/b><\/span><\/span><\/span>mh<\/b><\/span><\/span><\/sub><\/span> <\/b>= 12000m\/5400s = 2.2m\/sx3,6 <\/b><\/span><\/span>= 8 km\/h.<\/b><\/span><\/span><\/span><\/p>\n

Mulheres \"\" V<\/b><\/span><\/span><\/span>mm<\/b><\/span><\/span><\/sub><\/span> = \u2206S\/\u2206t<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>V<\/b><\/span><\/span><\/span>mm<\/b><\/span><\/span><\/sub><\/span> <\/b>= 10km\/(60\/90)h = 600\/90 <\/b><\/span><\/span>= 6.7 km\/h.<\/b><\/span><\/span><\/span><\/p>\n

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

02- <\/b><\/span><\/span><\/span>Reflex\u00e3o em meios unidimensionais (corda)<\/b><\/span><\/span><\/span><\/p>\n

Extremidade fixa<\/b><\/span><\/span><\/span>\u00a0\u2013 A <\/b><\/span><\/span><\/span>fonte (A)<\/b><\/span><\/span><\/span> provoca uma <\/b><\/span><\/span><\/span>oscila\u00e7\u00e3o completa<\/b><\/span><\/span><\/span> e a onda se propaga com velocidade V at\u00e9 o ponto B que est\u00e1 <\/b><\/span><\/span><\/span>fixo, preso, por exemplo, a uma parede.<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Quando o pulso <\/b><\/span><\/span>chega \u00e0 B<\/b><\/span><\/span><\/span>, <\/b><\/span><\/span>cada ponto<\/b><\/span><\/span><\/span> da corda aplica na parede uma <\/b><\/span><\/span>for\u00e7a\u00a0<\/b><\/span><\/span><\/span> e, pelo princ\u00edpio da a\u00e7\u00e3o e rea\u00e7\u00e3o, a <\/b><\/span><\/span>parede reagir\u00e1 sobre cada ponto<\/b><\/span><\/span><\/span> da corda com uma for\u00e7a de mesma intensidade, mesma dire\u00e7\u00e3o, mas <\/b><\/span><\/span>sentido contr\u00e1rio<\/b><\/span><\/span><\/span>, <\/b><\/span><\/span>produzindo um\u00a0pulso invertido\u00a0ap\u00f3s a reflex\u00e3o<\/b><\/span><\/span><\/span>, mas com a mesma velocidade V, pois o meio (corda \u00e9 o mesmo. A amplitude A tamb\u00e9m ser\u00e1 a mesma, supondo n\u00e3o haver perda de energia.<\/b><\/span><\/span><\/p>\n

Extremidade fixa \u2013 reflex\u00e3o ocorre com invers\u00e3o de fase.<\/b><\/span><\/span><\/span><\/p>\n

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

03- <\/b><\/span><\/span><\/span>Ao <\/b><\/span><\/span>n\u00edvel do mar onde a press\u00e3o atmosf\u00e9rica \u00e9 normal e vale 1 atm<\/b><\/span><\/span><\/span>, em uma <\/b><\/span><\/span>panela aberta<\/b><\/span><\/span><\/span> a \u00e1gua <\/b><\/span><\/span>ferve a 100<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C.<\/b><\/span><\/span><\/span> Se essa panela <\/b><\/span><\/span>for fechada<\/b><\/span><\/span><\/span>, o <\/b><\/span><\/span>vapor de \u00e1gua<\/b><\/span><\/span><\/span>que se forma no seu interior, <\/b><\/span><\/span>n\u00e3o<\/b><\/span><\/span><\/span><\/b><\/p>\n

\"\"<\/p>\n

se<\/b><\/span><\/span><\/span> <\/b>dissipa para o ambiente aumentando a press\u00e3o interna da panela,.<\/b><\/span><\/span><\/span>podendo chegar <\/b><\/span><\/span>at\u00e9 a 2atm,<\/b><\/span><\/span><\/span> onde a <\/b><\/span><\/span>\u00e1gua ferve a uma temperatura de aproximadamente 120<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>C<\/b><\/span><\/span><\/span>. Assim, os <\/b><\/span><\/span>alimentos cozinham em<\/b><\/span><\/span><\/span> <\/b>menor tempo, com menos gasto de energia t\u00e9rmica.<\/b><\/span><\/span><\/span> As <\/b><\/span><\/span>panelas de press\u00e3o possuem v\u00e1lvulas de<\/b><\/span><\/span><\/span> <\/b>seguran\u00e7a<\/b><\/span><\/span><\/span> que funcionam quando a <\/b><\/span><\/span>press\u00e3o atingir um ponto perigoso.<\/b><\/span><\/span><\/span><\/p>\n

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

04- <\/b><\/span><\/span><\/span>Os <\/b><\/span><\/span>tri\u00e2ngulos hachurados<\/b><\/span><\/span><\/span> da figura abaixo <\/b><\/span><\/span>s\u00e3o semelhantes<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>h\/80 = 1,80\/3,20<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>h <\/b><\/span><\/span><\/span>= 80×1,80\/3,20<\/b><\/span><\/span><\/p>\n

\"\"<\/p>\n

= 144\/3,20 <\/b><\/span><\/span>= 45 m.<\/b><\/span><\/span><\/span><\/p>\n

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

05- <\/b><\/span><\/span><\/span>Acelera\u00e7\u00e3o<\/b><\/span><\/span><\/span> \u00e9 <\/b><\/span><\/span>varia\u00e7\u00e3o de velocidade<\/b><\/span><\/span><\/span> pelo respectivo tempo e, como a <\/b><\/span><\/span>varia\u00e7\u00e3o de velocidade \u00e9 nula<\/b><\/span><\/span><\/span> a <\/b><\/span><\/span>acelera\u00e7\u00e3o tamb\u00e9m ser\u00e1 nula.<\/b><\/span><\/span><\/span><\/p>\n

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

06- <\/b><\/span><\/span><\/span>Watt de s\u00edmbolo W<\/b><\/span><\/span><\/span> \u00e9 unidade de <\/b><\/span><\/span>pot\u00eancia.<\/b><\/span><\/span><\/span><\/b><\/p>\n

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

07- <\/b><\/span><\/span><\/span>A express\u00e3o da intensidade <\/b><\/span><\/span>for\u00e7a magn\u00e9tica F<\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/sub><\/span> em fun\u00e7\u00e3o da <\/b><\/span><\/span>intensidade do campo magn\u00e9tico B<\/b><\/span><\/span><\/span> \u00e9<\/b><\/span><\/span><\/p>\n

F<\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/sub><\/span> = q.V.B \"\" B = F<\/b><\/span><\/span><\/span>m<\/b><\/span><\/span><\/sub><\/span>\/q.V.<\/b><\/span><\/span><\/span><\/p>\n

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

08- <\/b><\/span><\/span><\/span>a)<\/b><\/span><\/span><\/span> <\/b>Colocando as for\u00e7as que agem sobre cada cabo<\/b><\/span><\/span><\/span>, no ponto de encontro dos tr\u00eas e, em seguida <\/b><\/span><\/span>decompondo cada uma e considerando \u221a3 \u2248 1,7:<\/b><\/span><\/span><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>2x<\/b><\/span><\/span><\/span><\/sub> = T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/span><\/sub>cos<\/b><\/span><\/span><\/span>\u03b2<\/b><\/span><\/span> = <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span><\/span>2<\/b><\/span><\/span><\/span><\/sub><\/span>\/2.<\/b><\/span><\/span><\/span><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>1x<\/b><\/span><\/span><\/span><\/sub> = <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span><\/span>1<\/b><\/span><\/span><\/span><\/sub><\/span>cos<\/b><\/span><\/span><\/span><\/span>\u03b1<\/b><\/span><\/span><\/span> = <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span><\/span>1<\/b><\/span><\/span><\/span><\/sub><\/span>.(\u221a3)\/2<\/b><\/span><\/span><\/span><\/span>= 0,85T<\/b><\/span><\/span><\/span><\/span>1<\/b><\/span><\/span><\/span><\/sub><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>1y<\/b><\/span><\/span><\/span><\/sub> = T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/span><\/sub>.sen<\/b><\/span><\/span><\/span>\u03b1<\/b><\/span><\/span><\/span> <\/b>= T<\/b><\/span><\/span><\/span><\/span>1<\/b><\/span><\/span><\/span><\/sub><\/span>\/2.<\/b><\/span><\/span><\/span><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>2y<\/b><\/span><\/span><\/span><\/sub> = <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span><\/span>2<\/b><\/span><\/span><\/span><\/sub><\/span>sen<\/b><\/span><\/span><\/span><\/span>\u03b2<\/b><\/span><\/span><\/span> = <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span><\/span>2<\/b><\/span><\/span><\/span><\/sub><\/span>.(\u221a3)\/2<\/b><\/span><\/span><\/span><\/span>= 0,85T<\/b><\/span><\/span><\/span><\/span>2<\/b><\/span><\/span><\/span><\/sub><\/span><\/p>\n

\"\"<\/p>\n

Equil\u00edbrio na horizontal<\/b><\/span><\/span><\/span> \"\" 0,85T<\/b><\/span><\/span>1<\/b><\/span><\/span><\/sub> = 0,5T<\/b><\/span><\/span>2<\/b><\/span><\/span><\/sub> \"\" <\/b><\/span><\/span>T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> <\/b>=0,85T<\/b><\/span><\/span>1<\/b><\/span><\/span><\/sub>\/0,5 <\/b><\/span><\/span>= 1,7T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> (I).<\/b><\/span><\/span><\/span><\/p>\n

Equil\u00edbrio na vertical<\/b><\/span><\/span><\/span> \"\" T<\/b><\/span><\/span>1y<\/b><\/span><\/span><\/sub> + T<\/b><\/span><\/span>2y<\/b><\/span><\/span><\/sub> = P \"\" <\/b><\/span><\/span>0,5T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> + 0,85T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> = 80 (II).<\/b><\/span><\/span><\/span><\/p>\n

(I) em (II) \"\" <\/b><\/span><\/span>0,5T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> + 0,85.1,7T1 = 80 \"\" 0,5T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> + 1,445T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 80 \"\" 1,945T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 80 \"\" T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 80\/1,945 \"\"<\/b><\/span><\/span><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = 41 N.<\/b><\/span><\/span><\/span><\/p>\n

T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> = 1,7T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> \"\" <\/b><\/span><\/span><\/span>T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> = 1,7.41<\/b><\/span><\/span><\/span> \"\" T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span> = 69,7 N<\/b><\/span><\/span><\/span><\/p>\n

Obs. Todos os valores s\u00e3o aproximados<\/b><\/span><\/span><\/span><\/p>\n

b) <\/b><\/span><\/span><\/span>Quando os <\/b><\/span><\/span><\/span>\u00e2ngulos forem iguais a 45<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span>, pois sen45<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span> = cos45<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sup><\/span> = \u221a(2)\/2.<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

Nesse caso, <\/b><\/span><\/span>na vertical, 2T\u221a2\/2 = 80<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>T<\/b><\/span><\/span><\/span> = 80\/\u221a2 <\/b><\/span><\/span>= 40\u221a2 N = T<\/b><\/span><\/span><\/span>1<\/b><\/span><\/span><\/sub><\/span> = T<\/b><\/span><\/span><\/span>2<\/b><\/span><\/span><\/sub><\/span>.<\/b><\/span><\/span><\/span><\/p>\n

09- <\/b><\/span><\/span><\/span>Se ele f<\/b><\/span><\/span>lutua<\/b><\/span><\/span><\/span>, ent\u00e3o ele est\u00e1 em <\/b><\/span><\/span>equil\u00edbrio <\/b><\/span><\/span><\/span>e seu <\/b><\/span><\/span>peso<\/b><\/span><\/span><\/span> (vertical e para baixo) deve <\/b><\/span><\/span>ser igual<\/b><\/span><\/span><\/span> ao <\/b><\/span><\/span>empuxo <\/b><\/span><\/span><\/span>(vertical e para cima) que o fluido aplica nele.<\/b><\/span><\/span><\/p>\n

P = E<\/b><\/span><\/span><\/span> \"\" <\/b><\/span><\/span>\u03c1V<\/b><\/span><\/span><\/span>corpo<\/b><\/span><\/span><\/sub><\/span>.g = \u03c1<\/b><\/span><\/span><\/span>f<\/b><\/span><\/span><\/sub><\/span>.V<\/b><\/span><\/span><\/span>imerso<\/b><\/span><\/span><\/sub><\/span>.g \"\" <\/b><\/span><\/span><\/span>\u03c1.S.H = \u03c1<\/b><\/span><\/span><\/span>f<\/b><\/span><\/span><\/sub><\/span>.S.h<\/b><\/span><\/span><\/span>imersa<\/b><\/span><\/span><\/sub><\/span> \"\" 800.0,06 = 1200.h<\/b><\/span><\/span><\/span>imersa<\/b><\/span><\/span><\/sub><\/span> \"\" h<\/b><\/span><\/span><\/span>imersa<\/b><\/span><\/span><\/sub><\/span> = 48\/1200 \"\"<\/b><\/span><\/span><\/span><\/p>\n

\"\"<\/p>\n

h<\/b><\/span><\/span><\/span>imersa <\/b><\/span><\/span><\/sub><\/span>= 0,04m <\/b><\/span><\/span>= 4cm<\/b><\/span><\/span><\/span>.<\/b><\/span><\/span><\/p>\n

10- <\/b><\/span><\/span><\/span>Se a press\u00e3o \u00e9 <\/b><\/span><\/span><\/span>constante e vale P = 1,5.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span> Pa,<\/b><\/span><\/span><\/span> a transforma\u00e7\u00e3o \u00e9 <\/b><\/span><\/span><\/span>isob\u00e1rica<\/b><\/span><\/span><\/span> e o <\/b><\/span><\/span><\/span>trabalho realizado<\/b><\/span><\/span><\/span> pelo sistema \u00e9 <\/b><\/span><\/span><\/span>fornecido por W =P.(V \u2013 V<\/b><\/span><\/span><\/span>o<\/b><\/span><\/span><\/sub><\/span>) <\/b><\/span><\/span><\/span>= 1,5.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span>.(3,5.10<\/b><\/span><\/span><\/span>-6<\/b><\/span><\/span><\/sup><\/span>\u2013 3,0.10<\/b><\/span><\/span><\/span>-6<\/b><\/span><\/span><\/sup><\/span>) =1,5.10<\/b><\/span><\/span><\/span>5<\/b><\/span><\/span><\/sup><\/span>.0,5.10<\/b><\/span><\/span><\/span>-6<\/b><\/span><\/span><\/sup><\/span> \"\" <\/b><\/span><\/span><\/span>W<\/b><\/span><\/span><\/span> <\/b>= 0,75. 10<\/b><\/span><\/span><\/span>-1<\/b><\/span><\/span><\/sup><\/span> = <\/b><\/span><\/span><\/span>75.10<\/b><\/span><\/span><\/span>-3<\/b><\/span><\/span><\/sup><\/span> J<\/b><\/span><\/span><\/span><\/p>\n

 <\/p>\n

Voltar para os Exerc\u00edcios<\/a><\/span><\/h2>\n

\u00a0<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

RESOLU\u00c7\u00d5ES 01- Homens Vmh = \u2206S\/\u2206t Vmh = 12000m\/5400s = 2.2m\/sx3,6 = 8 km\/h. Mulheres Vmm = \u2206S\/\u2206t Vmm = 10km\/(60\/90)h = 600\/90 = 6.7 km\/h. R- B 02- Reflex\u00e3o em meios unidimensionais (corda) Extremidade fixa\u00a0\u2013 A fonte (A) provoca uma oscila\u00e7\u00e3o completa e a onda se propaga com velocidade V at\u00e9 o ponto B que est\u00e1 fixo, preso, por<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":908,"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-910","page","type-page","status-publish","hentry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/910","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=910"}],"version-history":[{"count":2,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/910\/revisions"}],"predecessor-version":[{"id":912,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/910\/revisions\/912"}],"up":[{"embeddable":true,"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/pages\/908"}],"wp:attachment":[{"href":"https:\/\/fisicaevestibular.com.br\/novo\/wp-json\/wp\/v2\/media?parent=910"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}