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purificação da arte
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I hate mondays
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espelho, reversos horizontais
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Why does a mirror reverse things horizontally but not vertically?
here’s a picture of a man lying down; a horizontal man:
You’ll notice that he’s wearing a black shoe on the foot closest to you, and a brown shoe on the foot farthest away from you (I’m deliberately not using the words “right” and “left”). He is also wearing an eye patch on the eye farthest away from you, but you can’t see that. Now let’s put a full-length mirror behind him, and examine the reflection:
The first thing to notice is that the mirror has not reversed things horizontally: the feet are still on the left of the picture and the head is still on the right. The next thing to notice is that it hasn’t reversed the image vertically either. The most important thing to notice is that (as far as the virtual man in the mirror is concerned) the brown shoe is now on the foot closest to you, and the black shoe is on the foot farthest away from you. Also, the eye patch is on the eye closest to you as opposed to the eye you can’t see. Does it now become clear? The mirror doesn’t reverse things horizontally (it may seem to, but that’s an illusion). It makes things that were on the back of the object that’s being reflected appear to be on the front. And vice versa.
Why, if you stand upright and look in a full length mirror, do you have the impression that your image has been horizontally reversed? Well, if you were to stand in front of a person, and they had a wrist watch on their left wrist, you’d have to move your eyes rightwards and downwards to see it. If you were standing behind them, you’d have to move your eyes leftwards and downwards to see it. If the features on the front of their body were somehow visible from the back, you’d still have to move your eyes leftwards and downwards to see the watch. That’s what the mirror does for you – shows you what’s on the front of the body without turning it round.
Why, if you write some text on a piece of paper and hold it up in front of the mirror, does the image of the text look horizontally reversed? That’s the equivalent of writing the text on something transparent – a sheet of glass, say – and then looking at it through the back of the sheet. All the letters are the wrong way round, and the word and letter order is backwards. Once again, the mirror is showing you what’s on the front of the object, as if you were looking through it.
EDIT: Many many thanks to the 158 thousand people who’ve read this piece since I posted it three and a half months ago, and to the 600 people who’ve upvoted it. A couple of people have reprimanded me for concocting the pictures (which I did, of course). So, as an answer to that criticism, here’s a photo I took today. A doll which I purchased from a charity shop (male equivalent of a Barbie); brown & black shoes; eye patch; reflection in a mirror:
I think that answers the question “Would this work if it was a real photo?”
(Why didn’t I get hold of a male model, 2 pairs of shoes, a full-length mirror & an eye-patch? ‘Cos I’m not made of money).
Está um tempo esquisito de verão ou é a nossa memória a pregar-nos partidas? – Atualidade – SAPO 24
Morreu Fausto Bordalo Dias, nome maior da música portuguesa – Atualidade – SAPO 24
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O cantautor tinha 75 anos. A notícia da morte foi confirmada pelo seu agente.
Source: Morreu Fausto Bordalo Dias, nome maior da música portuguesa – Atualidade – SAPO 24
O PRR e o registo de saúde electrónico – Opinião – SAPO 24
França Empurrar a extrema direita com a barriga
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Empurrar a extrema direita com a barriga
Edição por Ana Maria Pimentel
Era uma vez um homem, em França, que conseguiu conter Le Pen. Quis debater com ela, enfrentou-a, desmascarou as suas soluções populistas e a falta de “liberté, égalité, fraternité”. Mas isso foi na altura das presidenciais, agora nas legislativas Macron é presidente e não há ninguém do centro, nem da esquerda, para fazer esse trabalho.
E depois de o partido de extrema-direita de Jordan Bardella e Marine Le Pen, União Nacional (Rassemblement National), ter ontem ficado à frente na primeira volta das eleições legislativas, em França, com 33,15% dos votos, a Nova Frente Popular, de esquerda, ter ficado em segundo lugar com 28.14%. E a coligação centrista de Emmanuel Macron ter ficado pelos 21.27%. O presidente francês, Emmanuel Macron, decidiu convocar uma aliança “ampla” contra a extrema-direita.
Authentic Azorean Whaleboat sailing – in Furnas, São Miguel, Azores Islands | TERRA AZUL – YouTube
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Australian visa changes for 2024-25 | SBS News
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Under the government’s Migration Strategy, the age limit on some visas will be reduced and a ballot process will be introduced for others.
praia de augas santas RIBADEO GALIZA
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Elsa Cardoso Vicente and 14 others
Author Anthony Barcellos has died at age 72 – Sacramento, CAPortuguese American Journal
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Portuguese American author, Anthony Barcellos, has died at age 72 at the Mercy San Juan Medical Center in Sacramento, California, due to complications following a hemorrhagic stroke. Born in 1951, with roots on Terceira Island,
Se pudessem escolher apenas uma classificativa para correr, qual seria?
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É apenas uma curiosidade, mas não deixa de ser sintomática. No pré-Rali da Polónia, em que os pilotos do Mundial respondem a perguntas dos adeptos, houve uma bastante curiosa: “Se pudessem escolher apenas uma classificativa para correr, qual seria?” “Se só pudessem escolher um?” Troço das ‘Sete Cidades’…
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a mais antiga cultura
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DNA evidence confirms that Australia’s indigenous culture is one of the most ancient in the world, tracing their origins back to Africa. The first genome sequence of an Aboriginal person reveals that they left Africa around 60,000 – 75,000 years ago. This genetic study highlights that Aborigines are descendants of the first humans to migrate out of Africa, suggesting they may possess the oldest continuous culture on Earth.
Indigenous Australians were the first modern humans to navigate an unexplored region of Asia and Australia, according to Professor Eske Willerslev of the University of Copenhagen, who led the study. “Their journey was truly remarkable, requiring exceptional survival skills and courage,” he says. This discovery was made possible by analyzing a century-old lock of hair given to an anthropologist by an Aboriginal man, leading to insights about the ancestors of Aboriginal Australians.
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Morreu Manuel Cargaleiro, aos 97 anos. Presidente destaca um artista que “nunca deixou o cosmopolitismo significar desenraizamento” – Expresso
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O anúncio foi feito pelo Presidente da República numa nota de pesar “pela morte de Mestre Cargaleiro”. Na despedida, Marcelo lembra o último encontro com o artista, há semanas, em Lisboa, destacando o ceramista e pintor, “mas também desenhador, gravador e escultor” que deixa “a sua assinatura em igrejas, jardins ou estações de metro, e em inúmeras peças”