Foram encontradas 120 questões.
The lion and the four bulls
Clarke, M.
A lion used to walk about a field in which four bulls lived.
Many times he tried to attack them, but whenever he came near, they turned their tails toward one another so that whichever way the lion tried to attack, he would have to face the horns of one of them.
At last, however, the bulls started arguing with each other, and each went off to a different part of the field by himself. Then the lion attacked them one by one and soon had killed all four.
Ann Arbor: The University of Michigan Press, 1996.p.138
The messsage of the text can be summarized as:
Provas
Choose T for true and F for false. Then, choose the alternative which corresponds to the correct sequence.
( ) We always go home by bus or by car, never by foot.
( ) The tourists will leave in August 23.
( ) He came home on Sunday afternoon.
( ) She saw him on the end of the line.
Provas
Life on a desert island
Alexander,L.G.
Most of us have formed an unrealistic picture of life on a desert island. We sometimes imagine a desert island to be a sort of paradise where the sun always shines. Life there is simple and good. Ripe fruit falls from the trees and you never have to work.
There is also the other side of the picture: Life on a desert island is wretched - you either starve to death or live like Robison Crusoe waiting for a boat which never comes. Perhaps there is an element of truth in both these pictures, but few of us have had the opportunity to find out.
Two men who recently spent five days on a coral island whished they had stayed there no longer. They were taking a badly damaged boat from the Virgin Islands to Miami to have it repaired.
During the journey, their boat began to sink. They quickly loaded a small rubber dinghy with food, matches, and cans of beer and rowed for a few miles across the Caribbean until they arrived at a tiny coral island. There were hardly any trees on the island and there was no water to drink, but this didn’t prove to be a problem since the men collected rain-water in the rubber dinghy. As they had brought a spear gun with them, they had plenty to eat. They caught lobster and fish every day, and, as one of them put it, “ate like kings”. When a passing tanker rescued them five days later, both men were genuinely sorry that they had to leave.
New concept English. Developing skills: an integrated course for intermediate students.
“Life there is simple and good. Ripe fruit falls from the trees and you never have to work.” These sentences could be connected by the word:
Provas
Life on a desert island
Alexander,L.G.
Most of us have formed an unrealistic picture of life on a desert island. We sometimes imagine a desert island to be a sort of paradise where the sun always shines. Life there is simple and good. Ripe fruit falls from the trees and you never have to work.
There is also the other side of the picture: Life on a desert island is wretched - you either starve to death or live like Robison Crusoe waiting for a boat which never comes. Perhaps there is an element of truth in both these pictures, but few of us have had the opportunity to find out.
Two men who recently spent five days on a coral island whished they had stayed there no longer. They were taking a badly damaged boat from the Virgin Islands to Miami to have it repaired.
During the journey, their boat began to sink. They quickly loaded a small rubber dinghy with food, matches, and cans of beer and rowed for a few miles across the Caribbean until they arrived at a tiny coral island. There were hardly any trees on the island and there was no water to drink, but this didn’t prove to be a problem since the men collected rain-water in the rubber dinghy. As they had brought a spear gun with them, they had plenty to eat. They caught lobster and fish every day, and, as one of them put it, “ate like kings”. When a passing tanker rescued them five days later, both men were genuinely sorry that they had to leave.
New concept English. Developing skills: an integrated course for intermediate students.
The men on the island didn’t go thirsty because they:
Provas
A descoberta do elétron e sua interação com campos elétricos e magnéticos, através dos experimentos com a ampola de Crockes, possibilitou a idealização do modelo atômico de
Provas
Sobre um trilho de um banco óptico é colocado perpendicularmente um objeto real que se aproxima de um espelho. A imagem observada é sempre virtual e direita e o tamanho da imagem aumenta conforme o objeto se aproxima do espelho. Mas, mesmo a imagem aumentando de tamanho, é sempre menor que o tamanho do objeto.
Pode-se afirmar corretamente que o espelho utilizado
Provas
O circuito abaixo é constituído de uma fonte de alimentação ideal, 4 resistores ôhmicos e um amperímetro ideal.
O circuito apresenta também um dispositivo composto de uma barra condutora, de resistência elétrica nula, que normalmente fica afastada. Mas se o dispositivo for acionado, a barra irá encostar nos pontos A, B e C ao mesmo tempo, colocando-os em contato.
Nas condições iniciais, o amperímetro indica um determinado valor de intensidade de corrente elétrica.
Assinale a alternativa que apresenta o valor da resistência elétrica R, em ohms, para que a indicação no amperímetro não se altere, quando o dispositivo for acionado.
Provas
Um móvel, de dimensões desprezíveis, parte do repouso e seu movimento retilíneo é observado por um professor de Física.
Os valores das posições (x) desse móvel em função dos respectivos instantes de tempo (t) estão registrados na tabela a seguir.
| x(m) | t(s) |
| 0 | 0 |
| 2 | 1 |
| 8 | 2 |
| 18 | 3 |
| 32 | 4 |
| 50 | 5 |
| 72 | 6 |
Podemos afirmar, corretamente, que o móvel executa um movimento retilíneo .
Provas
Durante a pandemia da COVID-19, passou-se a usar na entrada dos lugares públicos um termômetro digital óptico para verificar se a pessoa que vai entrar no local não está no estado febril. Esse termômetro não necessita estar em contato com a pele da pessoa examinada, pois o mesmo mede a radiação térmica do corpo da pessoa.
É costume apontar para a testa de quem será examinado, pois normalmente é uma área que está descoberta. Porém, vários vídeos circularam nas redes sociais dizendo que essa prática era perigosa, pois os raios “emitidos” pelo termômetro, segundo os vídeos, poderiam prejudicar os neurônios das pessoas examinadas. Isso não tem nenhum fundamento, pois o termômetro não emite, mas sim, mede a irradiação eletromagnética emitida pela pessoa, através de um sensor ajustado para a faixa de frequência, cujo valor é proporcional à temperatura.
No espectro das ondas eletromagnéticas essa faixa de funcionamento do sensor do termômetro é chamada de
Provas
Partículas !$ \beta !$ são lançadas com uma velocidade de módulo igual a 227500 km/s, perpendicularmente a um campo magnético uniforme !$ \vec{B} !$ de intensidade 0,1 T, com o sentido indicado na figura. Essas partículas atingem um anteparo, no ponto C, a uma distância de 26 mm do orifício de entrada, ponto A, após percorrerem uma trajetória igual a uma semi-circunferência, conforme a figura.
Nessas condições foi possível medir a relação carga/massa dessas partículas no valor de C/kg.
Provas
Caderno Container