Questões - IME 2021 | Gabarito e resoluções

(IME - 2021/2022 - 1 fase) Considere a clula eletroqumica abaixo: Pt(s) | H2(g) | HCl(aq) || Hg2Cl2(s)| Hg(l) Admita, ainda, a reao a seguir: Hg2Cl2(s) + H2(g)2Hg(l) + 2HCl(aq) O potencial-padro da clula acima a 294,5 K +0,2678 V e a 302,5 K +0,2638 V. Considere que tanto a entalpia, quanto a entropia de reao mudam muito pouco para variaes de temperatura no muito amplas. A constante de Faraday 96500 C.mol-1. A entropia-padro da reao acima, a 298,15 K em J.(K.mol)-1, ser aproximadamente:

(IME - 2021/2022 - 2 fase) Text 3 Weight reduction of a carbon fibre composite wheel Stefan Czypionka and Frank Kienhofer Abstract The wheel of a passenger vehicle must be designed to be safe and light. (...) Manufacturing and testing carbon fibre reinforced plastics (CFRP) prototypes is expensive. Thus, it is advantageous to develop simulation models for composite weight reduction. The simulation models can provide insight into how lighter CFRP wheels can be designed. This study presents the design development of a CFRP wheel for a high-performance roadster; the CFRP wheel is offered by an automotive manufacturer as a high-performance option instead of aluminium wheels. Finite element (FE) simulations were initially conducted assuming an isotropic material. This initial model was used to eliminate stress concentrations and to design and manufacture an initial CFRP wheel. The CFRP wheel weight is 6.8 kg as compared to the original aluminium wheel which weighs 8.1 kg. This initial design passed the dynamic cornering fatigue test (the most stringent strength test for wheels). Thereafter the wheel was instrumented with strain gauges, and a bending moment was applied to the hub using a custom-built test rig. The test rig produced a static load equivalent to the dynamic cornering fatigue test (in which the applied bending moment varies sinusoidally). (...) 1. Introduction 1.1 Background The wheel is arguably one of the most important components of a road going vehicle. It is responsible for the transmission of power from the drive components of the vehicle to the road, while also enabling the vehicle to make directional changes. Overdesigning a wheel by adding material increases the wheel mass and rotational inertia which negatively affects the vehicles performance and efficiency. This has led to substantial development efforts to reduce the wheel weight and rotational inertia while simultaneously maintaining or increasing the material strength. A wheel must be designed to be safe and light. Numerous research studies have been published on the development of steel and aluminium wheels. Steel and aluminium alloy wheels have arguably reached the peak of possible weight reduction and composite materials offer the next advance. Despite the tremendous potential of carbon fibre as an automotive material due to high strength, low density and superior fatigue properties, (38) . Giger and Ermanni demonstrated the development process of a CFRP motorcycle rim. However, this wheel was not tested to certified standards. Rondina et al. investigated a high volume production method for carbon fibre wheels. The paper simulated the production process; however, no certified wheel appears to have been produced. As early as 1979, studies have been conducted into the viability of composites for use as automotive wheels. Unlike isotropic materials, CFRP components are expensive to test and certify. Even small changes in geometry to prevent failure or reduce stresses could cause a production line to be retooled during the development process and existing equipment to be scrapped. This research paper illustrates the development of a validated finite element (FE) model to investigate laminate configurations to improve the stiffness of the CFRP wheel and be 18% lighter than the original aluminium wheel. The case study is of an original equipment (OE) wheel designed and manufactured by Blackstone Tek (BST). (...) https://doi.org/10.1515/secm-2019-0018 Received Jan 28, 2019; accepted Feb 25, 2019. Adapted from: Weight reduction of a carbon fibre composite wheel. Available at: [Accessed on May, 3rd, 2021]. Choose the correct option that completes the following sentence. Composite wheels ______.

(IME - 2021/2022 - 1 fase) Uma amostra de 390 g de sulfito de clcio com 25% de impurezas, em massa, atacada por cido clordrico concentrado em um meio reacional a 2 atm e 300 K. Considere comportamento ideal de gases. Dados: massa molar do enxofre = 32 g.mol-1; massa molar do clcio = 40 g.mol-1; e massa molar do oxignio = 16 g.mol-1. Pode-se afirmar que o volume, em litros, de anidrido sulforoso obtido pelo consumo completo do sulfito :

(IME - 2021/2022 - 1 fase) Considere a representao simplificada dos seguintes decaimentos radioativos conhecidos: Com relao aos decaimentos acima, possvel afirmar que:

(IME - 2021/2022 - 2 fase) Text 2 Chariot Rodrigo Quijada Plubins Definition The chariot was a light vehicle, usually on two wheels, drawn by one or more horses, often carrying two standing persons, a driver and a fighter using bow-and-arrow or javelins. The chariot was the supreme military weapon in Eurasia roughly from 1700 BCE to 500 BCE but was also used for hunting purposes and in sporting contests such as the Olympic Games and in the Roman Circus Maximus. Horses were not used for transport, ploughing, warfare or any other practical human activity until quite late in history, and the chariot was the first such application. Donkeys and other animals were preferred in early civilizations. The Horse The horses main ecological niche was the Eurasian steppe; a very wide (4,800 km) and narrow (800 km on average) strip of grassland running roughly from Hungary to China, encompassing parts of what today is Ukrania, southern Russia, Kazakhstan, Uzbekistan, Turkmenistan, Kyrgyzstan, Tajikistan and Mongolia. For most of ancient history, the steppe - which means wasteland in Russian - was the home of nomadic societies whose economy was based on herding, complemented by hunting and, to a much lesser degree, sporadic, itinerant agriculture. No cities or settled communities existed in the steppe, save a very few spots. Steppe dwellers domesticated the horse for the purpose of breeding it for food like sheep and other animals already domesticated. That process is unfortunately poorly understood, and it occurred sometime before 2500 BCE. The wheel, an invention imported from the Middle East, had arrived in the steppe around 3100 BCE. The invention of the chariot in the steppe - perhaps originally meant as an improved tool for hunting - occurred roughly by 2000 BCE, probably in the area just east of the southern Ural mountains, where the oldest chariots have been unearthed. The word for horse appears just around this date for the first time in Mesopotamia, when an increase in north-south trade through Iran is attested. Invention of the Chariot The chariot then became a moving platform from which soldiers could shoot at enemies. Arrows and javelins were the main weapons used by the fighter on board, while a second person drove the chariot. The tactic was to move constantly, in and out of the battle, shooting from a distance. There is no clear explanation as to why humans invented the chariot first, before riding the horse directly, which seems more straightforward to us. A chariot was obviously more expensive than the horse alone, and chariots could not enter or properly manoeuver in landscapes where a mounted horse can, such as hills, marshes or forests. We know people tried mounting horses very early, as we have found drawings depicting it, but those seem rare experiments that did not seem to work. The most common scholarly suggestion is that horses at that time were weaker than in the present, unsuitable for supporting a man and only after a very long period of constant, selective breeding, did a stronger horse come into being. Horses started consistently to be mounted roughly a millennium and a half after the chariot was invented. The compound bow, invented sometime during the second millennium BCE, was the final ingredient for the rise of a deadly ensemble. Bow and arrow were much older, and the innovation of the compound bow was the use of two types of materials, inside and outside the bow, which gave it considerably more power. Compound bows were able to accurately hit a target 300 m away, and penetrate an armour 100 m away. It was the preferred weapon of charioteers and later horseback riding societies. Its power is reflected in the fact that these bows were last used in war as recently as the 19th century CE by the Chinese, well into the age of firearms. We have scarce knowledge of what happened with the communities in the steppe once the chariot was invented. We can assume that war intensified - and some evidence about it does exist -, and those who first or better graspedthe new invention stormed their neighbours, sizing valuable hunting and pasturing land rights. We truly understand the impact of the chariot only when this new form of warfare came out of the steppes and into the settled, agricultural lands. Charioteers Warfare The first reference to charioteers comes from Syria around 1800 BCE. Over the course of the next four centuries, chariots advanced into civilization, either by direct migration of steppe people or by diffusion, and it quickly came to be the preferred elite weapon. (...) Everywhere, in Europe, the Middle East, India, and China, all rulers, from petty chiefs to great pharaohs, took the chariot as their master weapon. They started depicting themselves riding chariots, waging wars in chariots, including chariots and horses in their tombs as symbols of power, and so on. Their surrounding aristocracy, of course, followed suit, so the elite forces in every polity came to be charioteers. The horse came to be a valuable military asset, no longer a food source. Horse breeding became key for these states, and all powerful kings aspired to have the proper stables to supply their armies with chariots; imports from the steppes, though, long remained their major source. The most famous chariot battle was that of Kadesh (1294 BCE), fought between the two superpowers of the time, Egypt and Hatti (Hittites), where some 50 chariots are presumed to have participated for each side. The small number of chariots compared to infantry troops is a good indicator of how effective the chariot was: in China, the ratio was up to 25 infantry soldiers per chariot. Decline in Use The use of the chariot declined very slowly, starting around 500 BCE (and yet, in some parts of Europe the technology was just arriving at that time). First and probably foremost, because horseback riding was developed in the steppes, and slowly but surely replaced the need for chariots. The first known forces mounting horses were those of the Scythians, steppe people who in the 7th century BCE attacked the Assyrian empire on horseback. Second, because infantry, formerly helpless against chariots, became more sophisticated due to the expanding use of iron weapons (from c. 1200 BCE onwards), and to new tactics in the form of phalanx formations. Fighting the invading Romans, the Celts were probably the last people who used chariots extensively, until around the 4th century CE. Adapted from: Chariot. World History Encyclopedia. Available at:https://www.worldhistory.org/chariot/ [Accessed on 5th March 2021]. VOCABULARY: BCE Before Common Era (or BC, Before Christ) CE Common Era (or AD, Anno Domini) Text 3 Weight reduction of a carbon fibre composite wheel Stefan Czypionka and Frank Kienhofer Abstract The wheel of a passenger vehicle must be designed to be safe and light. (...) Manufacturing and testing carbon fibre reinforced plastics (CFRP) prototypes is expensive. Thus, it is advantageous to develop simulation models for composite weight reduction. The simulation models can provide insight into how lighter CFRP wheels can be designed. This study presents the design development of a CFRP wheel for a high-performance roadster; the CFRP wheel is offered by an automotive manufacturer as a high-performance option instead of aluminium wheels. Finite element (FE) simulations were initially conducted assuming an isotropic material. This initial model was used to eliminate stress concentrations and to design and manufacture an initial CFRP wheel. The CFRP wheel weight is 6.8 kg as compared to the original aluminium wheel which weighs 8.1 kg. This initial design passed the dynamic cornering fatigue test (the most stringent strength test for wheels). Thereafter the wheel was instrumented with strain gauges, and a bending moment was applied to the hub using a custom-built test rig. The test rig produced a static load equivalent to the dynamic cornering fatigue test (in which the applied bending moment varies sinusoidally). (...) 1. Introduction 1.1 Background The wheel is arguably one of the most important components of a road going vehicle. It is responsible for the transmission of power from the drive components of the vehicle to the road, while also enabling the vehicle to make directional changes. Overdesigning a wheel by adding material increases the wheel mass and rotational inertia which negatively affects the vehicles performance and efficiency. This has led to substantial development efforts to reduce the wheel weight and rotational inertia while simultaneously maintaining or increasing the material strength. A wheel must be designed to be safe and light. Numerous research studies have been published on the development of steel and aluminium wheels. Steel and aluminium alloy wheels have arguably reached the peak of possible weight reduction and composite materials offer the next advance. Despite the tremendous potential of carbon fibre as an automotive material due to high strength, low density and superior fatigue properties, (38) . Giger and Ermanni demonstrated the development process of a CFRP motorcycle rim. However, this wheel was not tested to certified standards. Rondina et al. investigated a high volume production method for carbon fibre wheels. The paper simulated the production process; however, no certified wheel appears to have been produced. As early as 1979, studies have been conducted into the viability of composites for use as automotive wheels. Unlike isotropic materials, CFRP components are expensive to test and certify. Even small changes in geometry to prevent failure or reduce stresses could cause a production line to be retooled during the development process and existing equipment to be scrapped. This research paper illustrates the development of a validated finite element (FE) model to investigate laminate configurations to improve the stiffness of the CFRP wheel and be 18% lighter than the original aluminium wheel. The case study is of an original equipment (OE) wheel designed and manufactured by Blackstone Tek (BST). (...) https://doi.org/10.1515/secm-2019-0018 Received Jan 28, 2019; accepted Feb 25, 2019. Adapted from: Weight reduction of a carbon fibre composite wheel. Available at: [Accessed on May, 3rd, 2021]. Read the following statements about texts 2 and 3 I. Only Text 3 mentions a type of process that enhanced technology. II. Both texts mention invention developments which had the contribution of more than just one person or team. III. Text 2 mentions more events spaced out in time than Text 3. According to the mentioned texts, the correct statement(s) is (are):

(IME - 2021/2022 - 2 fase) Texto 1 Oficinas de artesanato e laboratrios de pesquisa! Dificilmente encontrveis em casas brasileiras, soa regra nas casas americanas. Em 1783, Benjamin Franklin inventa o para-raios; em 1787, John Fitch faz a sua primeira demonstraoda mquina a vapor no rio Delaware. Em 1877, Thomas Edison inventa o fongrafo; depois vem Goodyear, com a vulcanizao da borracha, e Gatling, com a metralhadora (...) Mesmo que existisse e noexiste essa coisa a que do o nome de vocao, como buscar no ambiente da senzala inspirao e gosto pelo trabalho construtivo e deiniciativa prpria? Onde inspirar-se? No exemplo dos bandeirantes? Nas sugestes dos engenhos? Nas lies dosantepassados latinos revigorados pela Renascena? (MOOG, Vianna. Bandeirantes e pioneiros: paralelos entre duas culturas. So Paulo: Globo, 1957, p. 164. Texto adaptado) Texto 2 Disponvel em: https://brainly.com.br/tarefa/3377084 A partir das ideias abordadas na prova de portugus e de redao a respeito do contexto da cincia, produza um texto dissertativo-argumentativo discorrendo sobre os desafios para a difuso da cincia e da tecnologia na sociedade contempornea.Em sua escrita, atente para as seguintes consideraes: 1. Privilegie a norma culta da lngua portuguesa. Eventuais equvocos morfossintticos, erros de regncia, concordncia, coeso e coerncia, bem como desvios da grafia vigente e a no observncia das regras deacentuao sero penalizados; 2. Seu texto devera ter entre 25 (vinte e cinco) a 30 (trinta) linhas escritas tinta azul ou preta. 3. No copie nem faa parfrasesde nenhuma parte dos textos apresentados neste exame, seja da prova de portugus ou da prova de ingls.