题目内容

可以采用______的方法使并励直流电动机反转。

A. 对调转子绕组接头
B. 改变外加电压极性
C. 对调励磁绕组接头
D. 对调转子和励磁绕组接头
E. 改变转子绕组接头

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下列关于三相异步交流电动机的叙述中,正确的有______。

A. 三相异步电动机可以通过改变转差率进行调速
B. 直接起动的电流约为额定电流的5~7倍,电动机严重过热,以致烧坏
C. 电动机在额定电压下起动称为直接起动
D. 直接起动的电路中,不需要时间继电器
E. 大功率的三相交流异步电动机可以采用星形—三角形降压启动

One of the questions that is coming into focus as we face growing scarcity of resources of many kinds in the world is how to divide limited resources among countries. In the international development community, the conventional wisdom has been that the 2 billion people living in poor countries could never expect to reach the standard of living that most of us in North America enjoy, simply because the world does not contain enough iron ore, protein, petroleum, and so on. At the same time, we in the United States have continued to pursue superaffluence as though there were no limits on how much we could consume. We make up 6 percent of the world’’s people; yet we consume one-third of the world’’s resources. As long as the resources we consumed each year came primarily from within our own boundaries, this was largely an internal matter. But as our resources come more and more from the outside world, "outsiders’’’ are going to have some say over the rate at which and terms under which we consume. We will no longer be able to think in terms of "our" resources and "their" resources, but only of common resources. As Americans consuming such a disproportionate share of the world’’s resources, we have to question whether or not we can continue our pursuit of superaffluence in a world of scarcity. We are now reaching the point where we must carefully examine the presumed link between our level of well-being and the level of material goods consumed. If you have only one crust of bread and get another crust of bread, your well-being is greatly enhanced. But if you have a loaf of bread, then an additional crust of bread doesn’’t make that much difference. In the eyes of most of the world today, Americans have their loaf of bread and are asking for still more. People elsewhere are beginning to ask why. This is the question we’’re going to have to answer, whether we’’re trying to persuade countries to step up their exports of oil to us or trying to convince them that we ought to be permitted to maintain our share of the world fish catch. The prospect of a scarcity of, and competition for, the world’’s resources requires that we reexamine the way in which we relate to the rest of the world. It means we find ways of cutting back on resource consumption that is dependent on the resources and cooperation of other countries. We cannot expect people in these countries to concern themselves with our worsening energy and food shortages unless we demonstrate some concern for the hunger, illiteracy and disease that are diminishing life for them. According to the text, it has long been believed that

A. people in poor countries fail to enjoy a higher standard of living.
B. people in underdeveloped countries are deprived of better living conditions.
C. most Americans know that the world’’s resources are going scarce.
D. it is impractical for all the people in the world to raise their living standards.

Do animals have rights This is how the question is usually put. It sounds like a useful, ground- clearing way to start. 71. Actually, it isn’’t, because it assumes that there is an agreed account of human fights, which is something the world does not have. On one view of rights, to be sure, it necessarily follows that animals have none. 72. Some philosophers argue that rights exist only within a social contract, as part of an exchange of duties and entitlements. Therefore, animals cannot have rights. The idea of punishing a tiger that kills somebody is absurd ,for exactly the same reason, so is the idea that tigers have rights. However, this is only one account ,and by no means an uncontested one. It denies rights not only to animals but also to some people―for instance, to infants, the mentally incapable and future generations. In addition, it is unclear what force a contract can have for people who never consented to it: how do you reply to somebody who says "I don’’t like this contract" The point is this: without agreement on the rights of people, arguing about the rights of animals is fruitless. 73. It leads the discussion to extremes at the outset: it invites you to think that animals should be treated either with the consideration humans extend to other humans, or with no consideration at all. This is a false choice. Better to start with another, more fundamental, question: is the way we treat animals a moral issue at all Many deny it. 74. Arguing from the view that humans are different from animals in every relevant respect, extremists of this kind think that animals lie outside the area of moral choice. Any regard for the suffering of animals is seen at a mistake―a sentimental displacement of feeling that should properly be directed to other humans. This view, which holds that torturing a monkey is morally equivalent to chopping wood, may seem bravely" logical". In fact it is simply shallow: the confused centre is right to reject it. The most elementary form of moral reasoning―the ethical equivalent of learning to crawl―is to weigh other’’s interests against one’’s own. This in turn requires sympathy and imagination: without which there is no capacity for moral thought. To see an animal in pain is enough, for most, to engage sympathy. 75. When that happens, it is not a mistake: it is mankind’’s instinct for moral reasoning in action, an instinct that should be encouraged rather than laughed at. Do animals have rights This is how the question is usually put. It sounds like a useful, ground- clearing way to start. 71. Actually, it isn’’t, because it assumes that there is an agreed account of human fights, which is something the world does not have. On one view of rights, to be sure, it necessarily follows that animals have none. 72. Some philosophers argue that rights exist only within a social contract, as part of an exchange of duties and entitlements. Therefore, animals cannot have rights. The idea of punishing a tiger that kills somebody is absurd ,for exactly the same reason, so is the idea that tigers have rights. However, this is only one account ,and by no means an uncontested one. It denies rights not only to animals but also to some people―for instance, to infants, the mentally incapable and future generations. In addition, it is unclear what force a contract can have for people who never consented to it: how do you reply to somebody who says "I don’’t like this contract" The point is this: without agreement on the rights of people, arguing about the rights of animals is fruitless. 73. It leads the discussion to extremes at the outset: it invites you to think that animals should be treated either with the consideration humans extend to other humans, or with no consideration at all. This is a false choice. Better to start with another, more fundamental, question: is the way we treat animals a moral issue at all Many deny it. 74. Arguing from the view that humans are different from animals in every relevant respect, extremists of this kind think that animals lie outside the area of moral choice. Any regard for the suffering of animals is seen at a mistake―a sentimental displacement of feeling that should properly be directed to other humans. This view, which holds that torturing a monkey is morally equivalent to chopping wood, may seem bravely" logical". In fact it is simply shallow: the confused centre is right to reject it. The most elementary form of moral reasoning―the ethical equivalent of learning to crawl―is to weigh other’’s interests against one’’s own. This in turn requires sympathy and imagination: without which there is no capacity for moral thought. To see an animal in pain is enough, for most, to engage sympathy. 75. When that happens, it is not a mistake: it is mankind’’s instinct for moral reasoning in action, an instinct that should be encouraged rather than laughed at.

第一节听下面5段对话。每段对话后有一个小题,从题中所给的[A]、[B]、[C]三个选项中选出最佳选项,并标在试卷的相应位置。听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。 What are the speakers going to do this evening

A. To see a friend.
B. To see a movie.
C. To see a play.

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