Questões - AFA 2019 | Gabarito e resoluções

(AFA - 2019) WHY DO SUPERVILLAINS FASCINATE US? A PSYCHOLOGICAL PERSPECTIVE Why are we fascinated by supervillains? Posing the question is much like asking why evil itself intrigues us, but theres much more to our continued interest in supervillains than meets the eye. Not only do Lex Luthor, Dracula and the Red Skull run unconstrained by conventional morality, they exist outside the limits of reality itself. Their evil, even at its most realistic, retains a touch of the unreal. But is our fascination with fantastic fiends1 healthy? From a psychological perspective, views vary on what drives our enduring interest in superhuman bad guys. Shadow confrontation: Psychiatrist Carl Jung believed we need to confront and understand our own hidden nature to grow as human beings. Healthy confrontation with our shadow selves can unearth new strengths (e.g., Bruce Wayne creating his Dark Knight persona to fight crime), whereas unhealthy attempts at confrontation may involve dwelling on or unleashing the worst parts of ourselves. Wish fulfillment: Sigmund Freud viewed human nature as inherently antisocial, biologically driven by the undisciplined ids pleasure principle to get what we want when we want it born to be bad but held back by society. Even if the psyche fully develops its ego (source of self-control) and superego (conscience), Freudians say the id still dwells2 underneath, and it wishes for many selfish things so it would love to be supervillainous. Hierarchy of needs: Humanistic psychologist Abraham Maslow held that people who havent met their most basic needs will have difficulty maturing. If starved for food, youre unlikely to feel secure. If starved for love and companionship, youll have trouble building self-esteem. People who dwell on their deficits may envy and resent others who have more than they do. Some people who are unable to overcome social shortcomings fantasize about obtaining any means, good or bad, to satisfy every need and greed. Conditioning: Ivan Pavlov would say we can learn to associate supervillains with other things we value like entertainment, strength, freedom or the heroes themselves. Behaviorist B.F. Skinner would likely argue that we can find it reinforcing to watch or read about supervillains, but without knowing whats reinforcing about them, thats a bit like saying its rewarding because its rewarding. Our Motivations for Seeking Out Supervillains Throughout history, humans have been captivated by stories of heroes facing off against superhuman foes3. But what specific rewards, needs, wishes and dark dreams do supervillains satisfy? Freedom: Superpowered characters enjoy freedoms the rest of us dont. Nobody can arrest Superman unless he lets them (at least not without kryptonite handcuffs). As much time as supervillains spend locked up, they seem to escape as often as they please, to run unconstrained by rules and regulations. Cosplayers who dress like Wonder Woman and Captain America cant do any crazy thing that crosses their minds without seeming to mock and insult our heroes, whereas those dressed as villains get to go wild. Supervillainy feels liberating. Power: Maybe you envy the power these evil characters wield4. While thats also a reason to adore superheroes, good guys dont ache to dominate. Stories like Watchmen and Kingdom Come show how heroes become menaces5 when they try to take over. So when dreaming of superpowers, maybe you relate to characters who dream of power as well, from the Scarecrow (who controls individuals fears) to Doctor Doom (whos perpetually out to dominate the world). Better villain than victim: Physiologically, anger activates us and feels better than anxiety or fear. One who feels victimized and cannot figure out constructive ways to stand up, be strong or become heroic might twist the need for self-assertion into destruction. Alternately, a healthy person simply might focus on how all characters assert themselves in any given story. Better villain equals better hero: A hero only appears as heroic as the challenge he or she must overcome. Great heroes require great villains. Without supercriminals, the worlds finest heroes seem like overpowered brutes nabbing thugs6 unworthy of them. Through myths, legends and lore across time, we have needed heroes who rise to the occasion, overcome great odds7 and take down giants. Facing our fears: Instead of dreading the darkness, you might reduce that dread by shining a light and seeing whats out there. Fiction can help us feel empowered and enlightened without literally traipsing into mob hangouts8 and poorly lit alleyways9. Exploring the unknown: Our need to challenge the unknown has driven the human race to cover the globe. This powerful curiosity makes us wonder about everything that baffles10 us, including the worlds worst fiends. Knowledge is power, or at least feels like it. When gritty details repulse us, exploring evil through the filter of fiction can help us contemplate humanitys worst without turning away or dwelling almost voyeuristically on real human tragedy. Even when the fiction is about improbable people doing impossible things, the storys fantastic nature reassures us that this cannot happen and therefore we dont have to turn away. Supervillains Ultimate Purpose In the end, our interest in supervillains can be healthy or unhealthy. Even the more maladaptive reasons for such fascination tend to arise from motivations that were originally healthy and natural frustrated drives that went the wrong way. Remember, though, that superheroic fiction ultimately begins and ends with the heroes. Comic book writers and artists create supervillains, who move in and out as guest stars and supporting cast, first and foremost to reveal how heroic the comics stars can be. (Adapted from https://www.wired.com/2012/07/why-do-supervillainsfascinate-us/) Glossary: 1. fiend an evil and cruel person 2. to dwell remain 3. foe an enemy 4. to wield influence, use power 5. menace threat 6. to nab thugs arrest criminals 7. odds probability 8. to traipse into mob hangouts walk among places where gangs, criminals meet 9. poorly lit alleyways narrow road or path with little light 10. to baffle confuse somebody completely Read the statements below and mark the option that contains the correct ones according to the text. I. Vulnerable people may have their self-esteem affected. II. Everybody is infatuated with antagonists. III. In a psychological perspective, antiheroes arent despised at all by the public. IV. The author reminds us that funny writers created supervillains stories. V. We have cherished defeated heroes and victorious antiheroes.

(AFA - 2019) WHY DO SUPERVILLAINS FASCINATE US? A PSYCHOLOGICAL PERSPECTIVE Why are we fascinated by supervillains? Posing the question is much like asking why evil itself intrigues us, but theres much more to our continued interest in supervillains than meets the eye. Not only do Lex Luthor, Dracula and the Red Skull run unconstrained by conventional morality, they exist outside the limits of reality itself. Their evil, even at its most realistic, retains a touch of the unreal. But is our fascination with fantastic fiends1healthy? From a psychological perspective, views vary on what drives our enduring interest in superhuman bad guys. Shadow confrontation: Psychiatrist Carl Jung believed we need to confront and understand our own hidden nature to grow as human beings. Healthy confrontation with our shadow selves can unearth new strengths (e.g., Bruce Wayne creating his Dark Knight persona to fight crime), whereas unhealthy attempts at confrontation may involve dwelling on or unleashing the worst parts of ourselves. Wish fulfillment: Sigmund Freud viewed human nature as inherently antisocial, biologically driven by the undisciplined ids pleasure principle to get what we want when we want it born to be bad but held back by society. Even if the psyche fully develops its ego (source of self-control) and superego (conscience), Freudians say the id still dwells2underneath, and it wishes for many selfish things so it would love to be supervillainous. Hierarchy of needs: Humanistic psychologist Abraham Maslow held that people who havent met their most basic needs will have difficulty maturing. If starved for food, youre unlikely to feel secure. If starved for love and companionship, youll have trouble building self-esteem. People who dwell on their deficits may envy and resent others who have more than they do. Some people who are unable to overcome social shortcomings fantasize about obtaining any means, good or bad, to satisfy every need and greed. Conditioning: Ivan Pavlov would say we can learn to associate supervillains with other things we value like entertainment, strength, freedom or the heroes themselves. Behaviorist B.F. Skinner would likely argue that we can find it reinforcing to watch or read about supervillains, but without knowing whats reinforcing about them, thats a bit like saying its rewarding because its rewarding. Our Motivations for Seeking Out Supervillains Throughout history, humans have been captivated by stories of heroes facing off against superhuman foes3. But what specific rewards, needs, wishes and dark dreams do supervillains satisfy? Freedom: Superpowered characters enjoy freedoms the rest of us dont. Nobody can arrest Superman unless he lets them (at least not without kryptonite handcuffs). As much time as supervillains spend locked up, they seem to escape as often as they please, to run unconstrained by rules and regulations. Cosplayers who dress like Wonder Woman and Captain America cant do any crazy thing that crosses their minds without seeming to mock and insult our heroes, whereas those dressed as villains get to go wild. Supervillainy feels liberating. Power: Maybe you envy the power these evil characters wield4. While thats also a reason to adore superheroes, good guys dont ache to dominate. Stories like Watchmen and Kingdom Come show how heroes become menaces5when they try to take over. So when dreaming of superpowers, maybe you relate to characters who dream of power as well, from the Scarecrow (who controls individuals fears) to Doctor Doom (whos perpetually out to dominate the world). Better villain than victim: Physiologically, anger activates us and feels better than anxiety or fear. One who feels victimized and cannot figure out constructive ways to stand up, be strong or become heroic might twist the need for self-assertion into destruction. Alternately, a healthy person simply might focus on how all characters assert themselves in any given story. Better villain equals better hero: A hero only appears as heroic as the challenge he or she must overcome. Great heroes require great villains. Without supercriminals, the worlds finest heroes seem like overpowered brutes nabbing thugs6unworthy of them. Through myths, legends and lore across time, we have needed heroes who rise to the occasion, overcome great odds7and take down giants. Facing our fears: Instead of dreading the darkness, you might reduce that dread by shining a light and seeing whats out there. Fiction can help us feel empowered and enlightened without literally traipsing into mob hangouts8and poorly lit alleyways9. Exploring the unknown: Our need to challenge the unknown has driven the human race to cover the globe. This powerful curiosity makes us wonder about everything that baffles10us, including the worlds worst fiends. Knowledge is power, or at least feels like it. When gritty details repulse us, exploring evil through the filter of fiction can help us contemplate humanitys worst without turning away or dwelling almost voyeuristically on real human tragedy. Even when the fiction is about improbable people doing impossible things, the storys fantastic nature reassures us that this cannot happen and therefore we dont have to turn away. Supervillains Ultimate Purpose In the end, our interest in supervillains can be healthy or unhealthy. Even the more maladaptive reasons for such fascination tend to arise from motivations that were originally healthy and natural frustrated drives that went the wrong way. Remember, though, that superheroic fiction ultimately begins and ends with the heroes. Comic book writers and artists create supervillains, who move in and out as guest stars and supporting cast, first and foremost to reveal how heroic the comics stars can be. (Adapted from https://www.wired.com/2012/07/why-do-supervillainsfascinate-us/) Glossary: 1. fiend an evil and cruel person 2. to dwell remain 3. foe an enemy 4. to wield influence, use power 5. menace threat 6. to nab thugs arrest criminals 7. odds probability 8. to traipse into mob hangouts walk among places where gangs, criminals meet 9. poorly lit alleyways narrow road or path with little light 10. to baffle confuse somebody completely The author concludes that

(AFA - 2019) Trs partculas, A, B e C, movimentam-se, com velocidades constantes, ao longo de uma mesma direo. No instante inicial, t0 = 0, a distncia entre A e B vale x, e entre B e C vale y, conforme indica a figura a seguir. Em t = 2 s, a partcula A cruza com a partcula B. Em t = 3 s, a partcula A cruza com a partcula C. A partcula C alcanar a partcula B no instante dado pela relao:

(AFA - 2019) Uma partcula, de massa 1 kg, descreve um movimento circular uniformemente variado, de raio 2,25 m, iniciando-o a partir do repouso no instante = 0. Em t = 2 s, o mdulo de sua velocidade vetorial () de 6 m/s, conforme figura abaixo. A intensidade da fora resultante sobre a partcula, no instante t = 1 s, em N, vale:

(AFA - 2019) Considere dois sistemas trmicos A e B constitudos de corpos perfeitamente esfricos, em condies normais de temperatura e presso, conforme figura abaixo. No sistema A, as esferas 1, 2, 3 e 4 so pequenas gotas esfricas de gua pura com massa respectivamente iguais a 1 g, 2 g, 4 g e 8 g. O sistema B constitudo das esferas macias e homogneas 5, 6, 7 e 8 de mesmo material, de calor especfico constante igual a 0,2 cal/g C e massa especfica igual a 2,5 g/cm. Os volumes dessas esferas so conhecidos e valem, respectivamente, 4, 5, 7 e 16 cm. Nessas condies, o nmero mximo de esferas do sistema A que podem ser permutadas simultaneamente com esferas do sistema B, de maneira que os sistemas A e B continuem com a mesma capacidade trmica inicial e com o mesmo nmero de esferas,

(AFA - 2019) Uma esfera, de dimenses desprezveis, sob ao de um campo gravitacional constante, est inicialmente equilibrada na vertical por uma mola. A mola ideal e se encontra com uma deformao x, conforme ilustrado na figura 1. O sistema esfera-mola posto, em seguida, a deslizar sobre uma superfcie horizontal, com velocidade constante, conforme indicado na figura 2. Nessa situao, quando o ngulo de inclinao da mola , em relao horizontal, sua deformao y. Nessas condies, o coeficiente de atrito cintico entre a esfera e a superfcie horizontal vale

(AFA - 2019) A montagem da figura a seguir ilustra a descida de uma partcula 1 ao longo de um trilho curvilneo. Partindo do repouso em A, a partcula chega ao ponto B, que est a uma distncia vertical H abaixo do ponto A, de onde, ento, lanada obliquamente, com um ngulo de 45 com a horizontal. A partcula, agora, descreve uma trajetria parablica e, ao atingir seu ponto de altura mxima, nessa trajetria, ela se acopla a uma partcula 2, sofrendo, portanto, uma coliso inelstica. Essa segunda partcula possui o dobro de massa da primeira, est em repouso antes da coliso e est presa ao teto por um fio ideal, de comprimento maior que H, constituindo, assim, um pndulo. Considerando que apenas na coliso atuaram foras dissipativas, e que o campo gravitacional local constante. O sistema formado pelas partculas 1 e 2 atinge uma altura mxima h igual a

(AFA - 2019) Um armrio, cujas dimenses esto indicadas na figura abaixo, est em repouso sobre um assoalho plano e horizontal. Uma pessoa aplica uma fora F constante e horizontal, cuja linha de ao e o centro de massa (CM) do armrio esto num mesmo plano vertical. Sendo o coeficiente de atrito esttico entre o assoalho e o piso do armrio igual a e estando o armrio na iminncia de escorregar, a altura mximaH na qual a pessoa poder aplicar a fora para que a base do armrio continue completamente em contato com o assoalho

QUESTO ANULADA!! (AFA - 2019) Um feixe de luz monocromtica incide em uma interface perfeitamente plana formada por dois meios com ndices de refrao absolutos n1 e n2, com n2 n1, conforme figura abaixo. Esse feixe d origem a dois outros feixes, o refletido R1e o refratado R1, com intensidades I1e I1, respectivamente. O ngulo de incidncia 1,, medido em relao normal N, pode ser alterado para um valor 2tal que , originando dois novos feixes, o refletido R2e o refratado R2, de intensidades, respectivamente I2e I2. Considere que os meios sejam perfeitamente homogneos, transparentes e istropos, que no haja dissipao da energia incidente, nem absoro de luz na interface. Nessas condies, so feitas as seguintes afirmativas sobre as intensidades dos raios refletidos e refratados. I. I1 I1 e I2 I2 II. I1 I2e I1 I2 III. I1 I1 e I2 I2 IV. I1 I2e I1 I2 V. I1 I1 e I2 I2 Assim, so corretas as afirmativas a) I e II b) III e IV c) IV e V d) II e III QUESTO ANULADA!!

(AFA - 2019) Duas lentes esfricas delgadas 1 e 2, com ndices de refrao e , respectivamente, so usadas para observar a figura plana mostrada abaixo, quando o observador, objeto e lente esto imersos em um meio homogneo, transparente e istropo com ndice de refrao n maior do que os ndices e. As imagens observadas so apresentadas nas figuras 1 e 2 em comparao com o objeto observado. Se a mesma observao for realizada, porm com o observador, objeto e lente imersos em um outro meio com ndice de refrao n menor do que e , das opes abaixo a que apresenta as imagens que podero ser observadas, respectivamente, pelas lentes 1 e 2 sero

(Epcar (Afa) 2019) Num instante t0 = 0 um capacitor de 2,5 mF, totalmente descarregado, ligado a uma fonte de 12 V por meio de uma chave Ch que colocada na posio 1, conforme figura abaixo. Em um determinado instante t1, o capacitor fica completamente carregado. Nessas condies, so feitas as seguintes afirmativas. I. Ao colocar a chave do circuito na posio 2, o capacitor ser descarregado atravs do resistor de 1 e sua diferena de potencial decrescer exponencialmente com o tempo, at completar o processo de descarga. II. Com a chave do circuito na posio 1, para qualquer instante de tempo t, tal que , o capacitor sofre um processo de carga, em que a corrente no circuito vai diminuindo linearmente com o tempo e tem sua intensidade nula quando t = t1. III. A energia potencial armazenada no capacitor no instante de tempo t1 vale 0,18 J. So verdadeiras as afirmativas

(AFA - 2019) Um corpo de massa m = 1 kg movimenta-se no sentido horrio, ao longo de uma trajetria circular de raio A, em movimento circular uniforme com velocidade angular igual a 2 rad/s, conforme a figura abaixo. Nessas condies, os sistemas massa-mola oscilando em movimento harmnico simples, a partir de t = 0, que podem representar o movimento dessa partcula, respectivamente, nos eixos x e y, so

(AFA - 2019) A figura abaixo representa dois harmnicos A e B, de frequncias, respectivamente, iguais a e , que podem ser estabelecidos em uma mesma corda, fixa em suas extremidades, e tracionada por uma fora de mdulo F. Nessas condies, a mesma razo, entre as frequncias, pode ser obtida entre as frequncias das ondas estacionrias representadas nos tubos sonoros abertos e idnticos A e B, indicados na opo

(AFA - 2019) Duas partculas eletrizadas A e B, localizadas num plano isolante e horizontal , esto em repouso e interligadas por um fio ideal, tambm isolante, de comprimento l igual a 3 cm, conforme ilustrado na figura abaixo. A partcula A est fixa e B pode mover-se, sem quaisquer resistncias sobre o plano. Quando B, que tem massa igual a 20 g, est em repouso, verifica-se que a fora tensora no fio vale 9 N. Imprime-se certa velocidade na partcula B, que passa a descrever um movimento circular uniforme em torno de A, de tal forma que a fora tensora no fio altera-se para 15 N. Desprezando as aes gravitacionais, enquanto a tenso no fio permanecer igual a 15 N, pode-se afirmar que a energia do sistema, constitudo das partculas A e B, ser, em J, de

(AFA - 2019) Trs condutores cilndricos 1, 2 e 3, de mesmo material e mesmo comprimento, sendo os condutores 2 e 3 ocos, tm suas sees retas apresentadas na figura a seguir. A respeito das resistncias eltricas R1, R2 e R3, dos condutores 1, 2 e3, respectivamente, pode-se afirmar que