Foram encontradas 412 questões.
Em uma aplicação, temos que alimentar uma carga com uma tensão equivalente à metade da tensão de alimentação. A resistência da carga varia e necessita-se obter um rendimento igual ou superior a 70%. Qual solução pode ser adotada?
Provas
Uma subestação industrial operando a plena capacidade alimenta uma carga indutiva de 1500 kW com fator de potência 0,8. Deseja-se adicionar uma carga indutiva de 250 kW com fator de potência de 0,85. Qual o procedimento para viabilizar essa instalação?
Provas
Em relação à corrente nominal de um motor de indução, considere as seguintes afirmativas:
1. É diretamente proporcional à potência.
2. É tanto maior quanto menor for o fator de potência.
3. Não é afetada pelo rendimento.
4. Se seu rendimento for menor que 0,5, o fator de potência tem efeito proporcional à corrente nominal.
Assinale a alternativa correta.
Provas
Quanto às linhas de transmissão e sistemas de distribuição em alta e baixa tensão utilizados pela COPEL, considere as afirmativas abaixo:
1. Uma linha de transmissão de 13,8 kV com três fases ligadas em Δ é composta por 3 cabos de fase.
2. Uma linha de transmissão de 13,8 kV com três fases ligadas em Y é composta por 2 cabos de fase e um neutro.
3. Quando a linha de transmissão de 13,8 kV com três fases ligadas em Δ deriva a um transformador de poste, este transforma os 13,8 kV trifásico em um sistema trifásico com 220 V entre as fases e 127 V entre fase e neutro.
4. O aparecimento do neutro na linha de baixa tensão deve-se ao fato de que o transformador que recebe a alta tensão do sistema de transmissão em 13,8 kV transforma-a em baixa tensão e muda a configuração de fases de 
.
Assinale a alternativa correta
Provas
Para dimensionar os condutores de um circuito de uma instalação residencial, deve-se adotar a seguinte seqüência:
Provas
São materiais isolantes para uso industrial:
Provas
O texto abaixo é referência para as questões 37 a 40
Engineering and the Industrial Revolution
The first phase of modern engineering emerged in the Scientific Revolution. Galileo`s Two New Sciences, which seeks systematic explanations and adopts a scientific approach to practical problems, is a landmark regarded by many engineer historians as the beginning of structural analysis, the mathematical representation and design of building structures. This phase of engineering lasted through the First Industrial Revolution, when machines, increasingly powered by steam engines, started to replace muscles in most production. While pulling off the revolution, traditional artisans transformed themselves to modern professionals. The French, more rationalistic oriented, spearheaded civil engineering with emphasis on mathematics and developed university engineering education under the sponsorship of their government. The British, more empirically oriented, pioneered mechanical engineering and autonomous professional societies under the laissez-faire attitude of their government. Gradually, practical thinking became sicentific in addition to intuitive, as engineers developed mathematical analysis and controlled experiments. Technical training shifted from apprenticeship to university education. Information flowed more quickly in organized meetings and journal publications as professional societies emerged.
(www.creating technology.org/history.htm)
According to the text, during the Scientific Revolution:
Provas
O texto abaixo é referência para as questões 37 a 40
Engineering and the Industrial Revolution
The first phase of modern engineering emerged in the Scientific Revolution. Galileo`s Two New Sciences, which seeks systematic explanations and adopts a scientific approach to practical problems, is a landmark regarded by many engineer historians as the beginning of structural analysis, the mathematical representation and design of building structures. This phase of engineering lasted through the First Industrial Revolution, when machines, increasingly powered by steam engines, started to replace muscles in most production. While pulling off the revolution, traditional artisans transformed themselves to modern professionals. The French, more rationalistic oriented, spearheaded civil engineering with emphasis on mathematics and developed university engineering education under the sponsorship of their government. The British, more empirically oriented, pioneered mechanical engineering and autonomous professional societies under the laissez-faire attitude of their government. Gradually, practical thinking became sicentific in addition to intuitive, as engineers developed mathematical analysis and controlled experiments. Technical training shifted from apprenticeship to university education. Information flowed more quickly in organized meetings and journal publications as professional societies emerged.
(www.creating technology.org/history.htm)
Consider the following afirmatives:
1. The French government supported higher education in engineering.
2. The British government`s attitude helped create autonomous professional societies.
3. The French and the British governments had similar attitudes concerning the development of engineering.
4. The focus of engineering was more scientific in France than in Great Britain.
According to the text:
Provas
O texto abaixo é referência para as questões 37 a 40
Engineering and the Industrial Revolution
The first phase of modern engineering emerged in the Scientific Revolution. Galileo`s Two New Sciences, which seeks systematic explanations and adopts a scientific approach to practical problems, is a landmark regarded by many engineer historians as the beginning of structural analysis, the mathematical representation and design of building structures. This phase of engineering lasted through the First Industrial Revolution, when machines, increasingly powered by steam engines, started to replace muscles in most production. While pulling off the revolution, traditional artisans transformed themselves to modern professionals. The French, more rationalistic oriented, spearheaded civil engineering with emphasis on mathematics and developed university engineering education under the sponsorship of their government. The British, more empirically oriented, pioneered mechanical engineering and autonomous professional societies under the laissez-faire attitude of their government. Gradually, practical thinking became sicentific in addition to intuitive, as engineers developed mathematical analysis and controlled experiments. Technical training shifted from apprenticeship to university education. Information flowed more quickly in organized meetings and journal publications as professional societies emerged.
(www.creating technology.org/history.htm)
According to the text, an important change in the first phase of modern engineering was:
Provas
O texto abaixo é referência para as questões 37 a 40
Engineering and the Industrial Revolution
The first phase of modern engineering emerged in the Scientific Revolution. Galileo`s Two New Sciences, which seeks systematic explanations and adopts a scientific approach to practical problems, is a landmark regarded by many engineer historians as the beginning of structural analysis, the mathematical representation and design of building structures. This phase of engineering lasted through the First Industrial Revolution, when machines, increasingly powered by steam engines, started to replace muscles in most production. While pulling off the revolution, traditional artisans transformed themselves to modern professionals. The French, more rationalistic oriented, spearheaded civil engineering with emphasis on mathematics and developed university engineering education under the sponsorship of their government. The British, more empirically oriented, pioneered mechanical engineering and autonomous professional societies under the laissez-faire attitude of their government. Gradually, practical thinking became sicentific in addition to intuitive, as engineers developed mathematical analysis and controlled experiments. Technical training shifted from apprenticeship to university education. Information flowed more quickly in organized meetings and journal publications as professional societies emerged.
(www.creating technology.org/history.htm)
According to the text, a landmark in engineering is:
Provas
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