Prática de Shadowing: Black Holes Explained – From Birth to Death - Aprenda a falar inglês com vídeo

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Black holes are one of the strangest things in existence.
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They don't seem to make any sense at all.
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Where do they come from?
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And what happens if you fall into one?
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Bye.
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Stars are incredibly massive collections of mostly hydrogen atoms that collapse from enormous gas clouds under their own gravity.
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In their core, nuclear fusion crushes hydrogen atoms into helium, releasing a tremendous amount of energy.
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This energy, in the form of radiation, pushes against gravity, maintaining a delicate balance between the two forces.
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As long as there is fusion in the core, a star remains stable enough.
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But for stars with way more mass than our own Sun, the heat and pressure at the core allow them to fuse heavier elements until they reach iron.
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Unlike all the elements that went before, the fusion process that creates iron doesn't generate any energy.
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Iron builds up at the center of the star until it reaches a critical amount, and the balance between radiation and gravity is suddenly broken.
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a fraction of a second, the star implodes, moving at about a quarter of the speed of light, feeding even more mass into the core.
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It's at this very moment
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that all the heavier elements in the universe are created as the star dies in a supernova explosion.
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This produces either a neutron star, or if the star is massive enough, the entire mass of the core collapses into a black hole.
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If you looked at a black hole, what you'd really be seeing is the event horizon.
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Anything that crosses the event horizon needs to be traveling faster than the speed of light to escape.
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In other words, it's impossible.
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So we just see a black sphere, reflecting nothing.
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But if the event horizon is the black part, what is the whole part of the black hole?
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The singularity.
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We're not sure what it is exactly.
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A singularity may be infinitely dense, meaning all its mass is concentrated into a single point in space, with no surface or volume.
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Or something completely different.
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Right now, we just don't know.
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It's like a dividing by zero error.
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things up like a vacuum cleaner.
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If we were to swap the Sun for an equally massive black hole, nothing much would change for Earth, except that we would freeze to death, of course.
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What would happen to you if you fell into a black hole?
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The experience of time is different around black holes.
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From the outside, you seem to slow down as you approach the event horizon, so time passes slower for you.
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At some point, you would appear to freeze in time, slowly turn red, and disappear.
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While from your perspective, you can watch the rest of the kind of like seeing into the future.
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Right now, we don't know what happens next, but we think it could be one of two things.
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One, the end.
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You die a quick death.
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A black hole curves space so much that once you cross the event horizon, there is only one possible direction.
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You can take this literally inside the event horizon.
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You can only go in one direction.
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It's like being in a really tight alley that closes behind you after each step.
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The mass of a black hole is so concentrated, at some point even tiny distances of a few centimeters,
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would mean that gravity acts with millions of times more force on different parts of your body.
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and more until you're a hot stream of plasma one atom wide.
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Two, you die a very quick death.
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Very soon after you cross the event horizon, you would hit a firewall and be terminated in an instant.
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Neither of these options are particularly pleasant.
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How soon you would die depends on the mass of the black hole.
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A smaller black hole would kill you before you even entered its event horizon, while you probably could travel inside a supermassive black hole for quite a while.
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As a rule of thumb, longer you live.
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Black holes come in different sizes.
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There are stellar mass black holes, with a few times the mass of the Sun and the diameter of an asteroid.
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And then there are these supermassive black holes, which are found at the heart of every galaxy and have been feeding for billions of years.
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Currently, the largest supermassive black hole known is S50014 +81,
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40 billion times the mass of which is 47 times the distance from the Sun to Pluto.
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As powerful as black holes are, they will eventually evaporate through a process called Hawking radiation.
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To understand how this works, we have to look at empty space.
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Empty space is not really empty, but filled with virtual particles popping into existence and annihilating each other again.
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When this happens right on the edge of a black hole, one of the virtual particles will be drawn into the black hole, and the other will escape and become a real particle.
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So the black hole is losing energy.
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This happens incredibly slowly at first, and gets faster as the black hole becomes smaller.
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When it has the mass of a mountain, it radiates with about the heat of our sun, and in the last second of its life, the black hole radiates away with the energy of billions of nuclear bombs in a huge explosion.
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But this process is incredibly slow.
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The biggest black holes we know might take up to a googol years to evaporate.
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This is so long that when the last black hole radiates away, nobody will be around to witness it.
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The universe will have become uninhabitable long before then.
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This is not the end of our story.
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There are loads more interesting ideas about black holes.
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We'll explore them in part two.
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A big thanks to Fraser Cain for help with this video.
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By the way, we've made some Kurzgesagt wallpaper in 4K for different screen sizes.
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You can get them on our Patreon page, which also helps us to make more videos.
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Like this December, the first month ever with 3 videos.
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you

Por que praticar a fala com este vídeo?

Assistir a vídeos como "Buracos Negros Explicados – Da Nascimento à Morte" é uma excelente maneira de aprender inglês com YouTube. Ao integrar seu conteúdo visual e auditivo, você não apenas absorve informações fascinantes sobre astrofísica, mas também melhora suas habilidades de prática de conversação em inglês. O vídeo é repleto de vocabulário técnico e expressões que vão enriquecer sua fluência.

Ao praticar a fala através da técnica de shadowspeak, você pode imitar a entonação e a pronúncia do falante nativo, ajudando a fixar seu aprendizado. Tente repetir as frases em voz alta logo após ouvi-las, prestando atenção na sua pronúncia e fluência. Essa prática não só ajuda na compreensão auditiva, mas também aumenta sua confiança ao falar.

Gramática & Expressões em Contexto

No vídeo, algumas estruturas gramaticais e expressões se destacam:

  • “If you fell into one” - A construção condicional é usada para explorar cenários hipotéticos.
  • “As long as there is fusion” - Aqui encontramos a expressão “as long as” que indica uma condição necessária.
  • “You can only go in one direction” - O uso de “can only” enfatiza uma limitação, uma estrutura útil em conversações sobre regras e restrições.

Essas frases ilustram como conectar ideias de forma clara e lógica em inglês. Considere usar essas expressões em suas próprias conversas, o que pode enriquecer seu vocabulário e melhorar sua habilidade de comunicação.

Armadilhas Comuns de Pronúncia

Algumas palavras e frases no vídeo podem ser desafiadoras para pronunciar:

  • “Black hole” - A combinação de sons pode ser difícil de dominar; preste atenção na ligação entre as palavras.
  • “Event horizon” - A pronúncia correta de "horizon" e a junção com "event" exige prática para soar natural.
  • “Singularity” - O ‘g’ pode ser confuso para falantes de outras línguas; pratique o som suave.

Leve tempo para treinar essas palavras, utilizando a técnica de shadow speak. Repita as frases em voz alta, imitando o falante do vídeo, e registre como cada palavra é pronunciada. Isso ajudará a superar as dificuldades comuns e fará com que você se sinta mais confortável ao falar.

O que é a Técnica de Shadowing?

Shadowing é uma técnica de aprendizado de idiomas com base científica, originalmente desenvolvida para o treinamento de intérpretes profissionais. O método é simples, mas poderoso: você ouve áudio em inglês nativo e repete imediatamente em voz alta — como uma sombra seguindo o falante com 1-2 segundos de atraso. Pesquisas mostram melhora significativa na precisão da pronúncia, entonação, ritmo, sons conectados, compreensão auditiva e fluência na fala.