2011-2012(1北科大校内竞赛试题及答案

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北科大2011-2012-1-大学物理AI 期中试卷及答案

北京科技大学 2011--2012 学年第一学期大学物理AI 期中试卷（A 卷）选择题（每题5分，共100分）1、几个不同倾角的光滑斜面，有共同的底边，顶点也在同一竖直面上．若使一物体（视为质点）从斜面上端由静止滑到下端的时间最短，则斜面的倾角应选(A) 60°； (B) 45°；(C) 30°； (D) 15°。

2、一质点作直线运动，某时刻的瞬时速度=v 2 m/s ，瞬时加速度2/2s m a -=，则一秒钟后质点的速度(A) 等于零； (B) 等于-2 m/s ；(C) 等于2 m/s ； (D) 不能确定。

3、某物体的运动规律为t k t 2d /d v v -=，式中的k 为大于零的常量．当0=t 时，初速为v 0，则速度v 与时间t 的函数关系是(A) 0221v v +=kt ； (B) 0221v v +-=kt ； (C) 02121v v +=kt ； (D) 02121v v +-=kt 。

4、某人骑自行车以速率v 向西行驶，今有风以相同速率从北偏东30°方向吹来，试问人感到风从哪个方向吹来？(A) 北偏东30°； (B) 南偏东30°；(C) 北偏西30°； (D) 西偏南30°。

5、质量为m 的物体自空中落下，它除受重力外，还受到一个与速度平方成正比的阻力的作用，比例系数为k ，k 为正值常量．该下落物体的收尾速度(即最后物体作匀速运动时的速度)将是 (A) k mg ； (B) k g 2 ； (C) gk ； (D) gk 。

6、质量分别为m 1和m 2的两滑块A 和B 通过一轻弹簧水平连结后置于水平桌面上，滑块与桌面间的摩擦系数均为μ，系统在水平拉力F 作用下匀速运动，如图所示．如突然撤消拉力，则刚撤消后瞬间，二者的加速度a A 和a B 分别为(A) a A =0 , a B =0. (B) a A >0 , a B <0.(C) a A <0 , a B >0. (D) a A <0 , a B =0.7、一公路的水平弯道平均半径为R ，路面的外侧高出内侧，并与水平面夹角为θ．要使汽车通过该段路面时不引起侧向摩擦力，则汽车的速率为题6用图(A)Rg ； (B) θtg Rg ； (C) θθ2sin cos Rg ； (D) θctg Rg 。

全国大学生英语竞赛(NECCS)历年真题(含完整答案)

2012 National English Contest forCollege Students(Level C – Preliminary)(总分：150分时间：120分钟)Part I listening Comprehension (30 marks)Section A (5 marks)In this section, you will hear five short conversations. Each conversation will be read only once .After each conversation, there will be a twenty-second pause. During the pause, read the question and the three choices marked A, B and C, and decide which is the best answer .Then mark the corresponding letter on the answer sheet with a single line through the centre.What does the man say we can do to deal with oil crisis?A. To make full use of oil.B. To use as little oil as possibleC. To find alternative energy.2. Where does this conversation most probably take place?A. In an insurance company.B. In a bank.C. In a supermarket.3. According to the man, who is going to take over the position they are talking about?A. Janice.B. Someone else.C. Meryl.4. What does the woman say about the man’s report for the meeting?A. He has to get it ready before tomorrow noon.B. He has done well enough.C. He has enough time to prepare it.5. How many people will be on the earth by the year 2020 according to the professor?A. Some 5.8 billion.B. Nearly 7 billion.C. Over 8.5 billion.Section B (10 marks)In this section, you will hear two long conversations. Each conversation will be read only once. At the end of each conversation, there will be a one-minute pause. During the pause, read the questions and the three choices marked A, Band C, and decide which is the best answer. Then mark the corresponding letter on the answer sheet with a single line through the centreConversation One6. What’s the main job of Simon’s organization?A. They send out radio signals to communicate with other planets.B. They look for life and intelligence on other planets.C. They study stars that have planets orbiting around them.7. Why does the organization search for radio signals from space?A. Their presence may prove the existence of aliens.B. They may help scientists find out how the universe started.C. They convey messages about life on the earth.8. Does Simon believe those stories about aliens visiting our planet?A. No, he doesn’t believe them at all.B. Yes, he does believe those stories because of his study.C. Yes, he believes them although he has no evidence.9. Which of the following factor is considered to be important in forming life according to the passage?A. Gravity.B. Minerals.C. Water.10. When did the “big bang” occur?A. No one knows.B. 12 billion years ago.C. 20 billion year ago.Conversation Two11. Why did Bob make the news last month?A. Because he criticized traditional jobsB. Because he earned a lot of money.C. Because he tried new strategies in finding a job.12. In which way do the bestsellers like “The Brand Called You”and “The Personal Branding Phenomenon” help people?A. They advise people to promote themselves as brands.B. They teach people how to be a perfect partner.C. They give people tips for job interview.13. When did Bob come up with the idea of using the internet to find a job?A. Ten years ago when he was a college student.B. When he began to do research between jobs.C. After he launched the campaign “Give Bob a Job”.14. What was the purpose of Bob’s making the video?A. To fulfill his ambition as a director.B. To sell his products like Teddy bears and T-shirts.C. To advertise his skills and talents.15. How can the internet help Bob in his job search exactly?A. By helping him make friends.B. By passing on the video he made.C. By providing job information for him.Section C (5 marks)In this section, you will hear five short news items. After each item, which will be read only once, there will be a pause. During the pause, read the question and the three choices marked A, B and C, and decide which is the best answer. Then mark the corresponding letter on the answer sheet witha single line through the centre.16. How many troops are going to withdraw from Afghanistan by the end of next year?A. 43,000.B. 10,000.C. 33,000.17. What is the finding of the study?A. Low-calorie foods may lead to more weight.B. High-calorie foods may lead to more weight.C. High-calorie foods may lead to less weight.18. What do the conflicting reports show about radiation?A. The radiation level given by Tokyo Electric is much smaller than that given by other tests.B. The radiation level given by other tests is smaller than that given by Tokyo Electric.C. The radiation level is close to 10,000 times the normal level.19. Why are Caribbean Service and Europe Today shut down by BBC?A. Because of their outdated services.B. Because of cuts in government funding.C. Because of lack of target audience.20. What’s the cause of demonstrations in cities and towns across Syria?A. They are calling for more freedom.B. Workers demand higher pay.C. Some thirty people were killed by the police.Section D (10 marks)In this section, you will hear a short passage. There are 10 missing words or phrases. Fill in the blanks with the exact words or phrases you hear. The passage will be read twice. Remember to write the answers on the answer sheet.Recovery from jetlag can take as long as a day for every time zone crossed. So if you’re flying east-west for your holiday or on business, it is likely to mean a few days of feeling tired or even unwell.Jetlag is the (21)__________ of the body’s natural cycle and some factors make it worse. The artificial atmosphere inside a plane can affect the body in a number of ways and add to the effects of jetlag.Exercising before flights helps to offset the effects on the body of reduced (22) _________, and aerobic exercise afterwards helps to reoxygenate it. Drink plenty of water. Children may need more. Drinking carrot juice before flying overcomes oxygen deficiency.Eat light, frequent meals. Heavy meals (23) __________ the blood circulation, which can lead to dizziness and fainting. For two weeks before you fly, eat plenty of food containing vitamins A and E; they will build up your (24) __________ and help to keep you fit. Sleep as much as you can before the flight and on it. On board, wear earplugs and eye pads because darkness (25) __________ secretion of the hormones that enhance sleep.Avoid alcohol, which restricts the brain’s oxygen intake. Like tea and coffee, alcohol increases the dehydration effect of flying. If you need to drink to relax, (26) __________ that the cabin environment intensifies the effect of alcohol.Wear loose, comfortable, warm clothes and limber up during flight. Sitting down for several hours slows down the (27) _________, leading to local stiffness, cramps and dizziness. Re-adjust to local time as soon as you can. Bright light helps the body stay alert, so if you are going somewhere sunny, stay outside.Do not smoke before or during the flight since smoking (28) ___________ the blood oxygen level. If you need to calm your nerves, try aromatherapy oils which have a sedative effect. (29) _________ your doctor before flying if you are on medication. The effects of some drugs are strengthened at high altitudes and some may produce (30) _________.Part II Vocabulary and Structure (15 marks)There are 15 incomplete sentences in this section. For each blank there are four choices marked A, B, C and D. Choose the one that best completes the sentence. Then mark the corresponding letter on the answer sheet with a single line through the centre.31. What we all work for is to free ________ time for the things we really want to do.A. offB. upC. asideD. in32. You _________ his words seriously. He was talking nonsense.A. won’t takeB. may not takeC. mustn’t have takenD. needn’t have taken33. Never hesitate to _________ the first opportunity that comes along.A. seizeB. drawC. who; thatD. obtain34. His mother ________ hated city life longed to return to the village in _______she grew up.A. that; whereB. who; whichC. who; thatD. who; where35. All things _______, I think I’d better take your advice.A. consideringB. to be consideredC. consideredD. have been considered36. Twelve European countries ________ over to the Euro on January 1st, 2002.A. transformedB. switchedC. reversedD. altered37. She isn’t anything ________ unpleasant as people say she is.A. as likeB. likeC. asD. like as38. Stop complaining. You really ________ my nerves.A. get downB. get alongC. get offD. get on39. There wasn’t _______ truth in what he said.A. a grain ofB. a ray ofC. a point ofD.a drop of40. ________ for my savings, I wouldn’t be able to survive these miserable days.A. Was it notB. Were it notC. Had it been notD. Hadn’t it been41. There was a power cut this morning. ________, I couldn’t do anything with my computer.A. SupposedlyB. PresumablyC. ConsequentlyD. Essentially42. Alarm clocks needlessly wake ______ households. I want to design something targeted at the individual sleeper.A. wholeB. totalC. fullD. high43. _______ both parties agree on these issues will a contract be signed soon.A. If onlyB. UnlessC. ShouldD. Only if44.—I’ve run out of cash. Could you lend me a few pounds this evening?—_____ I’ll just have to find time to get to the bank and make a withdrawal.A.I can lend you some now.B. I’m not sure I’ve got any either.C. Sorry, I haven’t got a penny in my account.D. My credit card must be left home.45. —We’re all going to the New Skyline Restaurant for our end-of-year get-together. Can we count you in?—Oh, thanks, Sara, but _____A. I didn’t find you then.B. I’ve been to the restaurant once.C. I’ll pass this time.D. I’ll meet you there at 5:00. Part III Cloze (10 marks)Read the following passage and fill in each blank with one word. Choose the correct word in one of the following three ways: according to the context, by using the correct form of the given word, or by using the given letters of the word. Remember to write the answers on the answer sheet.Did you know that for every 20,000 novels written, only one gets published? So the (46) ____ (likely) that I’ll ever fulfill my ambition of becoming a professional mystery writer doesn’t seem very high. But the prospect of turning my lifelong passion into my livelihood and achieving fame and (47) for ______ at the same time is just too exciting for me to be put off by dull statistics.So what does it (48) t_______ to become a writer? Reading is important—all writers need to research their genre thoroughly to familiarize themselves (49) _______ its codes and conventions. My bookshelves at home are stacked with the novels of all the great mystery writers, which I’ve read and in many cases, re-read, despite (50) _______ (know) all the time “who’d done it”.Of course, being a writer requires imagination. You have to develop your own personal style rather than simply copy the work of “the greats”. I’ve turned out (51) d________ of short crime stories for my university student magazine—some have been published, some not, but I’ve always aimed to produce original and imaginative material.Last but not (52) ________, successful writers possess enormous self-discipline. I’ve often sacrificed my social life in order to devote the necessary time and effort to producing a good quality story. And more than once that has meant (53) _______ the midnight oil.We’ve got a novel inside us. Getting it out in anywhere near publishable form is no (54) ______ task, but with imagination and determination, and the help of an expert on “master class”, who could possibly fail to (55) re_______ their ambition?Part IV Reading Comprehension (40 marks)Read the following passages. Each passage is followed byseveral questions. Respond to the questions usinginformation from the passage. Remember to write theanswers on the answer sheet.Section A (10 marks)Questions 56—60 are based on the following passage.The term culture shock was introduced for the first timein 1958 to describe the anxiety produced when a personmoves to a completely new environment. This term expresses the feeling of not knowing what to do or how to do things in a new environment. This term expresses the feeling of not knowing what to do or how to do things in a new environment. We can describe culture shock as the physical and emotional discomfort a person suffers when coming to live in a place different from the place of origin.Often, the way that we live before is not accepted or considered as normal in the new place. Everything is different, for example, not speaking the language, not knowing how to use banking machines, not knowing how to use telephones, and so forth.The symptoms of culture shock can appear at different times. Although a person can experience real pain from culture shock, it is also an opportunity for growing and learning new perspectives. Culture shock can help people develop a better understanding of themselves and stimulate personal creativity.Culture shock has many stages. Each stage can be ongoing, or appear only at certain times. In the first stage, the new arrival may feel very happy about all of the new experience. This time is called the honeymoon stage. Afterward, the second stage presents itself. A person may encounter some difficulties in daily life. For example, communication difficulties may occur, such as not being understood. In this stage, there may be feelings of impatience, anger and sadness. Transition between the old methods and those of the new country is a difficult process and takes time to complete. The third stage is characterized by gaining some understanding of the new culture. A new feeling of pleasure and sense of humor may be experienced. A person may start to feel a psychological balance. The individual is more familiar with the environment and wants to belong. This starts an evaluation of the old ways versus those of the new. In the fourth stage, the person realizes that the new culture has good and bad things to offer. This stage can be one of double integration or triple integration, depending on the number of cultures that the person has to process. This integration is characterized by a more solid feeling of belonging. The person starts to define himself or herself and establish goals for living. The fifth stage is the stage that is called the reentry shock. This occurs when a person returns to the newly acquired customs are considered improper in the old culture.Questions 56—60Complete the summary with words from the passage, changing the form where necessary, with only one word for each blank.Introduced in 1958, culture shock is a term used to (56) __________ physical and emotional discomfort people experience when they come to or live in a new place. Although many people suffer a lot from culture shock, it is an (57) _________ for personal improvement. The five stages of culture shock may last for a long time or show up once in a while. In the first stage, the (58) __________ stage, the new arrival might be OK with everything. Afterward, (59) ________ from old methods to the new one calls for time and energy. During the third and fourth stage, people may gain more understanding of the new culture and possess objective views. The double or triple integration is (60) __________ by a feeling of belonging. The last stage, called reentry shock, refers to the feeling people have when returning to their home country.Section B (10 marks)Questions 61-65 are based on the following passage.For some people, it would be unthinkable. But Gabe Henderson is finding freedom in a recent decision; he canceled his MySpace account. The 26 years old graduate student stopped his accountafter realizing that a lot of his online friends were really just acquaintances. “The superficial emptiness clouded the excitement I had once felt,” Henderson wrote in an article. “It seems we have lost, to some degree, the special depth that true friendship is about.”Journalism professor Michael Bugeja, who is a strong supporter of face-to-face communication, read Henderson’s column and saw it was a sign of hope. Though he’s not anti-technology, Bugeja often lectures students about “interpersonal intelligence”—knowing when, where, and for what purpose technology is most appropriate. He points out the students he’s seen walking across campus, holding hands with each other while talking on cell phones to someone else He’s also seen them in coffee shops, surrounded by people, but staring instead at a computer screen. “True friends,” he says, “need to learn when to stop blogging and go across campus to help a friend.”These days, young people are more wired than ever—but they’re also getting more worried. Increasingly, they’ve had to deal with online bullies, who are posting anything from embarrassing photos to online threats. And increasingly, young people also are realizing that things they post on their profiles can come back to hurt them when applying for schools or jobs.Social networking can be an “extremely effective” way to publicize events to large groups. It can even help build a sense of community on campus. People joined Facebook as a way to meet others. However, it has limitations. A good Internet profile could make even the most boring person seem some what interesting. People are also not always happy with text messages on the cell phones. Cell phones can be a quick way to say “have a good day”. But friends can also cancel a night out with a text message to avoid having to explain. “Our generation needs to get over this fear of confrontation and rejection.” Henderson says. “The focus needs to be on quality communication, in all ways.”Back in his life, Henderson is enjoying spending more face-to-face time with his friends and less with his computer. He says his decision to quit his social-networking Internet accounts was a good one. “I’m not sacrificing friends,” he says, “because if a picture, some basic information about their life and a Web page is all my friendship has become, then there was nothing to sacrifice to begin with.”Questions 61—63Decide whether the following statements are true (T) or false (F) according to the passage.61. Although Henderson quit MySpace, most of his online friends are actually close friends.62. According to Bugeja, young people should know when to use technology and when to stop using it.63. Social networking helps build a sense of communitybut has a negative effect on young people’s life if it isused inappropriately.Questions 64—65Answer the following questions briefly according to thepassage.64. What does Henderson lose by using social networkingwebsites like Myspace?65. What do young people need to overcome in order tofocus on quality communication?Section C (10 marks)Questions 66—70 are based on the following passage.“Five …Four …Three …Two …One …Seeya! ”and Chance McGuire, twenty-five, is airborne off a 600 –foot concrete dam in Northern California. In one second he falls 15 feet, in two seconds 60 feet, and after three seconds and 130 feet, he is flying at 66 miles an hour.McGuire is a practitioner of what he calls the king of all extreme sports. BASE—an acronym for building, antenna, span (bridge) and earth (cliffs)—jumping has one of the sporting world’s highest fatality rates: in its 18-year history, forty –six participants have been killed. Yet the sport has never been more popular, with more than a thousand jumpers in the United States, and more seeking to get into it every day. It is an activity without margin for error. If your chute malfunctions, don’t bother researching for a reserve—there isn’t time. There are no second chances.Still, the sport may be a perfect fit with the times. Americans may have more in common with McGuire than they know or care to admit. America has embarked on a national orgy of thrill seeking and risk taking. The rise of adventure and extreme sports such as BASE jumping, snowboarding, ice climbing, skateboarding, and paragliding is merely the most vivid manifestation of this new national behavior.The rising popularity of extreme sports speaks of an eagerness on the part of millions of Americans to participate in activities closer to the edge, where danger, skill, and fear combine to give weekend warriors and professional athletes alike a sense of pushing out personal boundaries. According to American Sports Data Inc., a consulting firm, participation in so-called extreme sports is way up. Snowboarding has grown 113 percent in five years and now boasts nearly 5.5 million participants. Mountain hiking, skateboarding, scuba diving—their growth curves reveal a nation that loves to play with danger. Contrast that with activities such as baseball, touch football, and aerobics, all of which were in steady decline throughout the 1990s.The pursuits that are becoming more popular have one thing in common: the perception that they are somehow more challenging than a game of touch football. “Every human being with two legs and two arms is going to wonder how fast, how strong, how enduring he or she is,”says Eric Perlman, a mountaineer and film maker specializing in extreme sports. “We are designed to experience or die.”Questions 66—68Complete the following sentences with information given in the passage in a maximum of 4 words for each blank.66. _______ rates doesn’t stop people from getting into BASE jumping every day.67. The rise of extreme sports manifests the national behavior of _______ and ________.68. The combination of fear, skill and danger gives both amateurs and professionals a sense of ______.Questions 69—70Choose the best answer according to the passage.69. Which of the following activities reveals a nation that loves to play activities closer to the edge?A. Touch football.B. Baseball.C. Scuba diving.D. Aerobics.70. What does Eric mean by saying “We are designed to experience or die”?A. Life with great challenges is a meaningful one.B. Life without great experiences is very common.C. People may die while doing extreme sports.D. Extreme sports are essential parts of human life.Section D (10 marks)Questions 71—75 are based on the following passage.Albert Einstein was one of the greatest thinkers the world has ever known. He formulated theories of relativity, successfully described the nature of the universe and came up with the most famous equation in the world. David Beckham is the footballer whose skills and precision have made him one of the most gifted sportsmen of his generation. Who is more intelligent?How Gardner’s theory of multiple intelligences (MI) dares us to put these two men on neighboring pedestals. Instead of regarding intelligence as a single quantity measurable by pen-and-paper tests, Gardner, an education professor at Harvard University, divides human intelligence into no fewer than eight separate categories ranging from mathematical to musical competence. (74)His ideas have provoked vigorous debate about how one defines intelligence. Gardner’s point is that quantity measures only one capacity, the sort of mental agility that is valued in academic achievement, and that this single number does not do justice to human potential. So he has created his own spheres of achievement. Some categories are easily reconcilable with general perceptions about IQ. For example, “linguistic” intelligence confers a mastery of language, and is the preserve of such people as poets, writers and linguists. “Logical mathematical”intelligence marks out people who take a reasoning approach to physical things, and seek underlying principles. Einstein is the standard –bearer of this group, which also includes philosophers. These two categories are the main components of what we generally think of as “intelligence”.“Musical” intelligence characterizes musicians, composers and conductors. “Spatial” intelligence is about being able to picture perspective, to visualize a world in one’s head with great accuracy. Chess players, artists and architects would rate highly in this category. Dancers, athletes and actors are lumped under the “bodily-kinesthetic”heading; these individual, like Beckham, are able to control their bodies and movements very carefully.Then come two types of “personal”intelligence-intrapersonal, the ability to gauge one’s own mood, feelings and mental states, and interpersonal, being able to gauge it in others and use the information. These two categories could be interpreted as emotional intelligence. Psychiatrists are particularly adept at the former, while religious leaders and politicians are seen as people who can exploit the latter.Charles Darwin is perhaps the perfect embodiment of the eighth intelligence –“naturalist”. This label describes people with a deep understanding of the natural world and its objects. Zoologists and botanists can count themselves among this group.(75)These eight categories certainly reflect the fact that, in these areas, there is a spectrum of human ability ranging from the hopeless to the brilliant. But are these really intelligences, or could these competences be more accurately described as gifts or talents?Questions 71—73Answer the following questions briefly according to the passage.71. What are the main components of “intelligence” we generally think of?72. What kind of abilities does emotional intelligence involve?73. Which intelligences are represented by Einstein and Beckham respectively?Questions 74—75Translate the underlined sentences in the passage into Chinese.74. His ideas have provoked vigorous debate about how one defines intelligence.75. These eight categories certainly reflect the fact that, in these areas, there is a spectrum of human ability ranging from the hopeless to the brilliant.Part V Translation (10 marks)Translate the following sentences into English, using the hints given in brackets. Remember to write the answer on the answer sheet.76. 既然没有退路了，我们不妨试试他的方法。

2011年北京科技大学数学竞赛试题

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第届北京市大学生数学竞赛全部试题解答

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第十三届北京市大学生（非数学专业）数学竞赛
本科甲、乙组试题
（2001 年 10 月 13 日上午 9:00~11:30）
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大学生科技知识竞赛精选题库及答案

大学生科技知识竞赛精选题库及答案1、有一种物质可以传送光线而不会将能量以热的形式浪费掉，它可以把手机信号放大10倍，让电脑的速度提高1万倍，它是：(B)A、氧化钾B、氮化镓C、氧化钴D、氧化镁2、2005年，沃伦和马歇尔荣获诺贝尔生理学或医学奖，以表彰他们对胃炎和消化性溃疡疾病的研究。

他们发现，绝大部分的十二指肠溃疡和胃溃疡都是由一种病菌引起的，这种病菌是：(A)A、幽门螺杆菌B、巴氏杆菌C、大肠杆菌D、念珠菌3、有一种气体在空气中的比例约为78%，其氧化物不仅参与地面臭氧的形成，还会导致全球变暖，造成生物多样性减少，这种气体是：(C)A、二氧化碳B、甲烷气体C、氮气D、氯气4、利用阳光映出的铜针阴影位置断定当时的时刻的计时器，在古代名为：（A）A、日晷B、铜壶滴漏C、钟表D、指南针5、在乾清宫门外两侧，陈设着十口金光闪闪的鎏金大铜缸，一方面它作为宫中的露天陈设品，请问还有什么作用？（B）A、洗澡B、救火C、罚人D、降温6、太和殿内地面用金砖铺成，烧成之后经过严格检查，达到何种程度方可使用？（B）第1页A、无裂缝B、敲之有声，断之无孔C、土质好，烧工精D、敲之无声7、飞机的航行灯有几种颜色：(D)A、6B、1C、4D、38、比赛用的足球重量是（B）A、365-400克B、396-453克C、435-483克D、400克-435克9、“第四媒体”的概念指的是：（B）A、多媒体B、网络媒体C、网上报纸D、手机10、人类下一次见到哈雷彗星应该是哪一年？（C）A、2026年B、2053年C、2062年D、2074年11、世界上第一个发明活字印刷术的是：（A）A、毕昇B、沈括C、蔡伦D、谷登堡12、英国科学家弗莱明与哪一种发明有关：（B）A、狂犬病疫苗B、青霉素C、白日咳疫苗D、甲肝疫苗13、世界上最大的瀑布之一奥赫拉比斯瀑布位于南非哪个城市：（B）A、好望角B、开普敦C、德班D、安哥拉14、君子兰是哪个城市的市花：（B）A、哈尔滨B、长春C、沈阳15、世界上三大地震带是：（B）A、环太平洋地震带、印度洋地震带和海岭地震带第2页B、环太平洋地震带、亚欧地震带和海岭地震带C、亚欧地震带、北极洋地震带和环太平洋地震带D、印度洋地震带、北冰洋地震带和环太平洋地震带16、当地震发生时你在家里（楼房），应如何避震：（A）A、躲在桌子等坚固家具的下面，房屋倒塌后能形成三角空间的地方B、去楼道C、原地不动D、跳楼17、人体血液中红细胞可存活多少天？（B）A、80天B、120天C、150天D、100天18、生物体的基本单位是：（D）A、器官C、组织D、细胞19、下列等重量营养素产能最多的是：（B）A、蛋白质B、脂肪C、糖类D、盐类20、父亲的血型为A型，母亲的血型为AB型，所生子女的血型不可能为（C）。

附：北京科技大学(北京市物理竞赛获奖名单)xls-Sheet1

2012年北京市大学生物理竞赛获奖名单序号 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 姓名章刘洋胡超丁民涛王晓吴春华张赢唐汉琦陈榴吴科言郑禹付伟男杨柳陈善军刘冰施王影姜培扬王军格夏建军郑晓虎张赛时岩刘扬胡婧高扬关喜嘉管明李景县章晓敏苏晓波程斌陈腊梅孙趁义于祥圣王愿贾文鹏吴洁慧葛佶莛张翔杨冰学生证号 41111115 41112110 41112088 41164007 41179081 41179084 41155081 41159052 41130100 41103016 41104024 41112076 41151021 41111065 41142055 41103017 41121125 41016056 41140207 41093018 41122015 41121041 41136026 41142085 41104048 41164031 41130108 41130089 41112105 41140092 41167016 41167041 41112001 41130036 41140088 41167015 41171073 41140140 41151020 学校名称学院获奖等级一等奖一等奖一等奖一等奖一等奖一等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖二等奖三等奖三等奖北京科技大学土木北京科技大学土木北京科技大学土木北京科技大学数理北京科技大学管理北京科技大学管理北京科技大学计通北京科技大学计通北京科技大学材料北京科技大学高工北京科技大学机械北京科技大学土木北京科技大学自动化北京科技大学土环北京科技大学机械北京科技大学高工北京科技大学冶金北京科技大学土环北京科技大学机械北京科技大学机械北京科技大学材料北京科技大学冶金北京科技大学材料北京科技大学机械北京科技大学机械北京科技大学数理北京科技大学材料北京科技大学材料北京科技大学土环北京科技大学机械北京科技大学机械北京科技大学化生北京科技大学土木北京科技大学材料北京科技大学机械北京科技大学化生北京科技大学管理北京科技大学机械北京科技大学自动化

2011-2012大学物理AI试卷及参考答案北京科技大学

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【VIP专享】全国大学生英语竞赛C类(2012到2013真题以及答案)

2012 National English Contest forCollege Students(Level C – Preliminary)(总分：150分时间：120分钟)Part II Vocabulary and Structure (15 marks)There are 15incomplete sentences in this section. For each blank there are four choices marked A, B, C and D. Choose the one that best completes the sentence. Then mark the corresponding letter on the answer sheet with a single line through the centre.A. offB. upC. asideD. inA. won’t takeB. may not takeC. mustn’t have takenD.needn’t have takenA. seizeB. drawC. who; thatD. obtainA. that; whereB. who; whichC. who; thatD. who; whereA. consideringB. to be consideredC. consideredD. have been consideredA. transformedB. switchedC. reversedD. alteredA. as likeB. likeC. asD. like as2011年全国大学生英语竞赛C类试题及参考答案A. get downB. get alongC. get offD. get onA. a grain ofB. a ray ofC. a point ofD. a drop ofA. Was it notB. Were it notC. Had it been notD. Hadn’t it beenA. SupposedlyB. PresumablyC. ConsequentlyD. EssentiallyA. wholeB. totalC. fullD. highA. If onlyB. UnlessC. ShouldD. Only if44.—I’ve run out of cash. Could you lend me a few pounds this evening?—_____ I’ll just have to find time to get to the bank and make a withdrawal.A.I can lend you some now.B. I’m not sure I’ve got any either.C. Sorry, I haven’t got a penny in my account.D. My credit card must be left home.A. I didn’t find you then.B. I’ve been to the restaurant once.C. I’ll pass this time.D. I’ll meet you there at 5:00.Part III Cloze (10 marks)Read the following passage and fill in each blank with one word. Choose the correct word in one of the following three ways: according to the context, by using the correct form of the given word, or by using the given letters of the word. Remember to write the answers on the answer sheet.Did you know that for every 20,000 novels written, only one gets published? So the (46) ____ (likely) that I’ll ever fulfill my ambition of becoming a professional mystery writer doesn’t seem very high. But the prospect of turning my lifelong passion into my livelihood and achieving fame and (47) for ______ at the same time is just too exciting for me to be put off by dull statistics.So what does it (48) t_______ to become a writer? Reading is important—all writers need to research their genre thoroughly to familiarize themselves (49) _______ its codes and conventions. My bookshelves at home are stacked with the novels of all the great mystery writers, which I’ve read and in many cases, re-read, despite (50) _______ (know) all the time “who’d done it”.Of course, being a writer requires imagination. You have to develop your own personal style rather than simply copy the work of “the greats”. I’ve turned out (51) d________ of short crime stories for my university student magazine—some have been published, some not, but I’ve always aimed to produce original and imaginative material.Last but not (52) ________, successful writers possess enormous self-discipline. I’ve often sacrificed my social life in order to devote the necessary time and effort to producing a good quality story. And more than once that has meant (53) _______ the midnight oil.We’ve got a novel inside us. Getting it out in anywhere near publishable form is no (54) ______ task, but with imagination and determination, and the help of an expert on “master class”, who could possibly fail to (55) re_______ their ambition?Part IV Reading Comprehension (40 marks)Read the following passages. Each passage is followed by several questions. Respond to the questions using information from the passage. Remember to write the answers on the answer sheet.Section A (10 marks)Questions 56—60 are based on the following passage.The term culture shock was introducedfor the first time in 1958 to describe the anxietyproduced when a person moves to a completelynew environment. This term expresses thefeeling of not knowing what to do or how to dothings in a new environment. This termexpresses the feeling of not knowing what to do or how to do things in a new environment. We can describe culture shock as the physical and emotional discomfort a person suffers when coming to live in a place different from the place of origin.Often, the way that we live before is not accepted or considered as normal in the new place. Everything is different, for example, not speaking the language, not knowing how to use banking machines, not knowing how to use telephones, and so forth.The symptoms of culture shock can appear at different times. Although a person can experience real pain from culture shock, it is also an opportunity for growing and learning new perspectives. Culture shock can help people develop a better understanding of themselves and stimulate personal creativity.Culture shock has many stages. Each stage can be ongoing, or appear only at certain times. In the first stage, the new arrival may feel very happy about all of the new experience. This time is called the honeymoon stage. Afterward, the second stage presents itself. A person may encounter some difficulties in daily life. For example, communication difficulties may occur, such as not being understood. In this stage, there may be feelings of impatience, anger and sadness. Transition between the oldmethods and those of the new country is a difficult process and takes time to complete. The third stage is characterized by gaining some understanding of the new culture. A new feeling of pleasure and sense of humor may be experienced. A person may start to feel a psychological balance. The individual is more familiar with the environment and wants to belong. This starts an evaluation of the old ways versus those of the new. In the fourth stage, the person realizes that the new culture has good and bad things to offer. This stage can be one of double integration or triple integration, depending on the number of cultures that the person has to process. This integration is characterized by a more solid feeling of belonging. The person starts to define himself or herself and establish goals for living. The fifth stage is the stage that is called the reentry shock. This occurs when a person returns to the newly acquired customs are considered improper in the old culture.Questions 56—60Complete the summary with words from the passage, changing the form where necessary, with only one word for each blank.Introduced in 1958, culture shock is a term used to (56) __________ physical and emotional discomfort people experience when they come to or live in a new place. Although many people suffer a lot from culture shock, it is an (57) _________ for personal improvement. The five stages of culture shock may last for a long time or show up once in a while. In the first stage, the (58) __________ stage, the new arrival might be OK with everything. Afterward, (59) ________ from old methods to the new one calls for time and energy. During the third and fourth stage, people may gain more understanding of the new culture and possess objective views. The double or triple integration is (60) __________ by a feeling of belonging. The last stage, called reentry shock, refers to the feeling people have when returning to their home country.Section B (10 marks)Questions 61-65 are based on the following passage.For some people, it would be unthinkable. But Gabe Henderson is finding freedom in a recent decision; he canceled his MySpace account. The 26 years old graduate student stopped his account after realizing that a lot of his online friends were really just acquaintances. “The superficial emptiness clouded the excitement I had once felt,” Henderson wrote in an article. “It seems we have lost, to some degree, the special depth that true friendship is about.”Journalism professor Michael Bugeja, who is a strong supporter of face-to-face communication, read Henderson’s column and saw it was a sign of hope. Though he’s not anti-technology, Bugeja often lectures students about “interpersonal intelligence”—knowing when, where, and for what purpose technology is most appropriate. He points out the students he’s seen walking across campus, holding hands with each other while talking on cell phones to someone else He’s also seen them in coffee shops, surrounded by people, but staring instead at a computer screen. “True friends,” he says, “need to learn when to stop blogging and go across campus to help a friend.”These days, young people are more wired than ever—but they’re also getting more worried. Increasingly, they’ve had to deal with online bullies, who are posting anything from embarrassing photos to online threats. And increasingly, young people also are realizing that things they post on their profiles can come back to hurt them when applying for schools or jobs.Social networking can be an “extremely effective” way to publicize events to large groups. It can even help build a sense of community on campus. People joined Facebook as a way to meet others. However, it has limitations. A good Internet profile could make even the most boring person seem some what interesting. People are also not always happy with text messages on the cell phones. Cell phones can be a quick way to say “have a good day”. But friends can also cancel a night out with a text message to avoid having to explain. “Our generation needs to get over this fear of confrontation and rejection.” Henderson says. “The focus needs to be on quality communication, in all ways.” Back in his life, Henderson is enjoying spending more face-to-face time with his friends and less with his computer. He says his decision toquit his social-networking Internet accounts was a good one. “I’m not sacrificing friends,” he says, “because if a picture, some basic information about their life and a Web page is all my friendship has become, then there was nothing to sacrifice to begin with.”Questions 61—63Decide whether the following statements are true (T) or false (F) according to the passage.61. Although Henderson quit MySpace, most of his online friends are actually close friends.62. According to Bugeja, young people should know when to use technology and when to stop using it.63. Social networking helps build a sense of community but has a negative effect on young people’s life if it is used inappropriately.Questions 64—65Answer the following questions briefly according to the passage.64. What does Henderson lose by using social networking websites like Myspace?65. What do young people need to overcome in order to focus on quality communication?Section C (10 marks)Questions 66—70 are based on the following passage.“Five … Four … Three … Two…One …See ya! ” and ChanceMcGuire, twenty-five, is airborneoff a 600 –foot concrete dam inNorthern California. In one secondhe falls 15 feet, in two seconds 60feet, and after three seconds and130 feet, he is flying at 66 miles anhour.McGuire is a practitioner of what he calls the king of all extreme sports. BASE—an acronym for building, antenna, span (bridge) and earth (cliffs)—jumping has one of the sporting world’s highest fatality rates: in its 18-year history, forty –six participants have been killed. Yet the sport has never been more popular, with more than a thousand jumpers in the United States, and more seeking to get into it every day. It is an activity without margin for error. If your chute malfunctions, don’t bother researching for a reserve—there isn’t time. There are no second chances.Still, the sport may be a perfect fit with the times. Americans may have more in common with McGuire than they know or care to admit. America has embarked on a national orgy of thrill seeking and risk taking. The rise of adventure and extreme sports such as BASE jumping, snowboarding, ice climbing, skateboarding, and paragliding is merely the most vivid manifestation of this new national behavior.The rising popularity of extreme sports speaks of an eagerness on the part of millions of Americans to participate in activities closer to the edge, where danger, skill, and fear combine to give weekend warriors and professional athletes alike a sense of pushing out personal boundaries. According to American Sports Data Inc., a consulting firm, participation in so-called extreme sports is way up. Snowboarding has grown 113 percent in five years and now boasts nearly 5.5 million participants. Mountain hiking, skateboarding, scuba diving—their growth curves reveal a nation that loves to play with danger. Contrast that with activities such as baseball, touch football, and aerobics, all of which were in steady decline throughout the 1990s.The pursuits that are becoming more popular have one thing in common: the perception that they are somehow more challenging than a game of touch football. “Every human being with two legs and two arms is going to wonder how fast, how strong, how enduring he or she is,” says Eric Perlman, a mountaineer and film maker specializing in extreme sports. “We are designed to experience or die.”Questions 66—68Complete the following sentences with information given in the passage in a maximum of 4 words for each blank.66. _______ rates doesn’t stop people from getting into BASE jumping every day.67. The rise of extreme sports manifests the national behavior of _______ and ________.Questions 69—70Choose the best answer according to the passage.69. Which of the following activities reveals a nation that loves to play activities closer to the edge?A. Touch football.B. Baseball.C. Scuba diving.D. Aerobics.70. What does Eric mean by saying “We are designed to experience or die”?A. Life with great challenges is a meaningful one.B. Life without great experiences is very common.C. People may die while doing extreme sports.D. Extreme sports are essential parts of human life.Section D (10 marks)Questions 71—75 are based on the following passage.Albert Einstein was one of the greatest thinkers the world has ever known. He formulated theories of relativity, successfully described the nature of the universe and came up with the most famous equation in the world. David Beckham is the footballer whose skills and precision have made him one of the most gifted sportsmen of his generation. Who is more intelligent?How Gardner’s theory of multiple intelligences (MI) dares us to put these two men on neighboring pedestals. Instead of regarding intelligence as a single quantitymeasurable by pen-and-paper tests, Gardner, an education professor at Harvard University, divides human intelligence into no fewer than eight separate categories ranging from mathematical to musical competence. (74)His ideas have provoked vigorous debate about how one defines intelligence. Gardner’s point is that quantity measures only one capacity, the sort of mental agility that is valued in academic achievement, and that this single number does not do justice to human potential. So he has created his own spheres of achievement. Some categories are easily reconcilable with general perceptions about IQ. For example, “linguistic” intelligence confers a mastery of language, and is the preserve of such people as poets, writers and linguists. “Logical mathematical” intelligence marks out people who take a reasoning approach to physical things, and seek underlying principles. Einstein is the standard –bearer of this group, which also includes philosophers. These two categories are the main components of what we generally think of as “intelligence”.“Musical” intelligence characterizes musicians, composers and conductors. “Spatial” intelligence is about being able to picture perspective, to visualize a world in one’s head with great accuracy. Chess players, artists and architects would rate highly in this category. Dancers, athletes and actors are lumped under the “bodily-kinesthetic” heading; these individual, like Beckham, are able to control their bodies and movements very carefully.Then come two types of “personal” intelligence-intrapersonal, the ability to gauge one’s own mood, feelings and mental states, and interpersonal, being able to gauge it in others and use the information. These two categories could be interpreted as emotional intelligence. Psychiatrists are particularly adept at the former, while religious leaders and politicians are seen as people who can exploit the latter.Charles Darwin is perhaps the perfect embodiment of the eighth intelligence –“naturalist”. This label describes people with a deep understanding of the natural world and its objects. Zoologists and botanists can count themselves among this group.(75)These eight categories certainly reflect the fact that, in these areas, there is aspectrum of human ability ranging from the hopeless to the brilliant. But are these really intelligences, or could these competences be more accurately described as gifts or talents?Questions 71—73Answer the following questions briefly according to the passage.71. What are the main components of “intelligence” we generally think of?72. What kind of abilities does emotional intelligence involve?73. Which intelligences are represented by Einstein and Beckham respectively? Questions 74—75Translate the underlined sentences in the passage into Chinese.74. His ideas have provoked vigorous debate about how one defines intelligence.75. These eight categories certainly reflect the fact that, in these areas, there is a spectrum of human ability ranging from the hopeless to the brilliant.Part V Translation (10 marks)Translate the following sentences into English, using the hints given in brackets. Remember to write the answer on the answer sheet.76. 既然没有退路了，我们不妨试试他的方法。

北科大2011-2012学年度第二学期高等数学期中试卷

北京科技大学2011--2012学年第二学期高等数学AII 期中试卷院(系) 班级学号姓名考场说明: 1、要求正确地写出主要计算或推导过程, 过程有错或只写答案者不得分； 2、考场、学院、班、学号、姓名均需写全, 不写全的试卷为废卷; 3、涂改学号及姓名的试卷为废卷；4、请在试卷上答题，在其它纸张上的解答一律无效.一、填空题（本题共36分，每小题4分）1. 设a x x a y D ≤≤-≤≤0,0:22(a 为正常数)，由二重积分的几何意义知:⎰⎰=--Ddxdy y x a 222 .2. 设23(,,)23A x y z zi x j y k =++，则=-)3,1,2(A. 3. 设),(y x f 具有一阶连续导数，且⎪⎪⎭⎫⎝⎛=z y y x f u ,，则d u =. 4. 累次积分⎰⎰⎰=x d f d d I 0)(ξηζζηξ 的定积分表达式为 .5. 函数32yz xy u +=在点(1，2，－1)处最大方向导数的值为 . 6. 设π32),(,5,2===b a b a，向量b a A 17+=λ与b a B-=3垂直，则=λ . 7. 设f 为可微函数， 222z y x r ++=，则=)(grad r f .8. 设Ω是由221x y +=与0z =, 2z =所围成的圆柱体，则⎰⎰⎰Ω=+dv y x)(22．9. 设可微函数),(y x f 对任意实数)0(>t t 满足),(),(y x tf ty tx f =，而(1,2,2)P -是),(y x f z =上一点，且4)2,1(1=-'f ，则此曲面在点P 处的切平面方程为 .装订线内不得答题自觉遵守考试规则，诚信考试，绝不作弊二、选择题（本题共36分，每小题4分）10. 已知),(y x f 在点),(00y x 的偏导数存在，则【】.(A) ),(y x f 在点),(00y x 连续 (B)),(y x f 在点),(00y x 可微．(C) ),(0y x f 在点0x 连续 (D)),(y x f 在点),(00y x 有任意方向的方向导数． 11. 设有闭区域1:22≤+y x D ，则二重积分d Dx y 的值等于【】.(A)π53． (B) π43． (C) π76． (D) π83． 12. 设),(v u f 具有二阶连续偏导数，且),(22y x xy f z =，则=∂∂∂yx z 2 【】. (A) 12222231132152222f y x f y x f xy f x yf ''+''+''+'+'．(B) 122222311315222f y x f y x f xy yf ''+''+''+'． (C) 1222223113212222f y x f y x f xy f x yf ''+''+''+'+'．(D) 1222221132152222f y x f xy f xy f x yf ''+''+''+'+'．13. 曲线0,6222=++=++z y x z y x 在点)1,2,1(-处的切线方程为【】.(A)112211--=+=-z y x ． (B) 210211-=+=-z y x ． (C) 110211-=+=-z y x ． (D) 110211--=+=-z y x ． 14. 双紐线22222)(y x y x -=+所围成区域的面积可用定积分表示为【】.(A) ⎰402cos 2πθθd ． (B) ⎰402cos 4πθθd ． (C) ⎰402cos πθθd ． (D)⎰42cos 21πθθd ．15. 设函数),(y x f 连续，则二次积分1sin 2d (,)d xx f x y y ππ=⎰⎰【】.(A) 10sin d (,)d xy f x y x ππ+⎰⎰． (B)10arcsin d (,)d yy f x y x ππ-⎰⎰．(C)1arcsin 02d (,)d xy f x y x ππ+⎰⎰． (D)1arcsin 02d (,)d yy f x y x ππ-⎰⎰．16. 设⎰⎰⎰Ω=dudvdw w v u f z y x F ),,(),,(, 其中{}(,,),,u v w a u x b v y c w z Ω=≤≤≤≤≤≤，则=∂∂∂∂zy x F 3 【】. (A) (,,)f u v w ． (B) (,,)f x v w ． (C) (,,)f x y w ． (D) (,,)f x y z ．17. 三次积分⎰⎰⎰---+++=2222)(302221)(y y yy y x dz z y x f dx dyI 写成球面坐标的形式为【】.(A)⎰⎰⎰πϕθππϕϕθsin sin 02224)(sin dr r f r d d ． (B)⎰⎰⎰πϕθππϕϕθsin sin 0224)(sin dr r f r d d ．(C)⎰⎰⎰πϕθππϕϕθsin sin 02226)(sin dr r f r d d ． (D)⎰⎰⎰πϕθππϕϕθsin sin 0226)(sin dr r f r d d ．若两直线λ12111-=+=-z y x 与z y x =-=+11相交，则=λ 【】. (A) 1． (B) 32． (C) 45-． (D) 45．三、解答题(本题共2小题,每题9分，满分18分)19. 设),(y x u 具有二阶连续偏导数，它满足关系式22220u u x y∂∂-=∂∂, x x x u =)2,(， 2)x =，求 )2,(),2,(2211x x u x x u '''' ，)2,(12x x u ''． 22y x z +=被平面1=++z y x 截成一椭圆，求原点到这椭圆的最长与最短距离.装订线内不得答题自觉遵守考试规则，诚信考试，绝不作弊四、证明题(本题共2小题,每题5分，满分10分)21. 设0)0(,1)0(=='f f ,连续)(u f '，且2222222()()d x y z t F t f x y z v ++≤=++⎰⎰⎰，证明：π54)(lim 5=+→tt F t .22. 设)(x f 在闭区间],[b a 上连续，利用二重积分性质证明：()22()d ()()d bbaaf x xb a f x x ≤-⎰⎰．。

2012年试卷

北京科技大学 2014--2015 学年第一学期
工程流体力学试卷（A）
院(系) 班级学号姓名
占课程平时成绩考核成占小计绩 80% 20% 课程考核成绩
试卷卷面成绩（满分 80 分）题号得分一二三四五六七八九十
得分
一、单选题（每题 2 分，共 30 分）
工程流体力学 A 试卷
第 4 页共 6 页
5. （5 分）采用皮托-静压管测量空气的流速，压差计中水银柱高度为 h = 50mm，空气的密度 ρa = 1.273kg/m3，水银密度 Hg 13600 kg m3 ，求空气的流速。
自觉遵装守考订试线规则内，诚不信考得试，答绝不题作弊
6. （5 分）水平放置的两块无限大平行平板间充满了粘性流体，平板间距离为 h。已知上平板以等速度 U 沿 x 轴正方向运动，下板固定。忽略质量力，xy 平面上此流动满足的基本方程为
u v 0 x y u u 1 p 2 u 2 u v u ， y x x 2 y 2 x 2v 2v u v v v 1 p 2 2 y y x y x
1. 按流体力学连续介质的概念，流体质点是指
自觉遵装守考订试线规则内，诚不信考得试，答绝不题作弊
(A) 流体的分子 (B) 流体内的固体颗粒 (C) 无大小的几何点 (D) 几何尺寸与流动空间相比是极小量，又含有大量分子的微元体 2. 从力学的角度分析，一般流体和固体的区别在于流体 (A) 能承受拉力，平衡时不能承受切应力 (B) 不能承受拉力，平衡时不能承受切应力 (C) 不能承受拉力，平衡时能承受切应力 (D) 能承受拉力，平衡时也能承受切应力 3. 以下关于流体粘性的说法，不正确的是 (A) 流体的粘性随温度的升高而增大 (B) 粘性是在运动状态下流体具有抵抗剪切变形能力的量度 (C) 流体的粘性具有传递运动和阻滞运动的双重作用 (D) 粘性是流体的固有属性 4. 静止流体中压强的分布规律 (A) 仅适合于不可压缩流体 (B) 仅适合于理想流体 (C) 仅适合于粘性流体 (D) 既适合于理想流体、又适合于粘性流体

2011-2012-2-AII期末考试试卷A及答案

三、计算题（每题 10 分，共 40 分）
得分
1、把质量为 6kg、比热容（单位质量物质的热容）为 500J/ (kg ·K)的铁棒加热到 327º C,然后浸入一大桶 27 º C 的水中。求在此冷却过程中系统（包括铁棒和桶中的水）总的熵变。
大学物理 AII 试卷
第 4 页共 7 页
得分
9、下列物体为绝对黑体的是（ (A) 不辐射可见光的物体； (B) 不辐射任何光线的物体； (C) 不能反射可见光的物体； (D) 不能反射任何光线的物体。
）
大学物理 AII 试卷
第 2 页共 7 页
10、下列各组量子数中，哪一组可以描述原子中电子的状态？（ (A) n 2 , L 2 ， ml 0 ， ms 1 2 ； (C) n 1 , L 2 , ml 1 ， ms 1 2 ；
2 x

0 ) 0.1cos( t 5 x ) 或（ 0.1cos( t 5 x ) ）3 分 2 2 7 = ，O 点的相位为，则 OQ 的相位差是 3 2 2 3 6
2 分
（3）利用旋转矢量图，此时 Q 的相位为
7 70 7 OQ 2 0.4, OQ m cm 0.233m 23.3cm 6 30 3
2 (A) ( p 2 c 2 Ek ) / 2Ek ； 2 (C) p 2 c 2 Ek ；
）
(B) ( pc Ek ) 2 / 2Ek ；
2 (D) ( p 2 c 2 Ek ) / 2 Ek 。
8、关于光电效应有下列说法： (1) 任何波长的可见光照射到任何金属表面都能产生光电效应； (2) 若入射光的频率均大于一给定金属的红限，则该金属分别受到不同频率的光照射时，释出的光电子的最大初动能也不同； (3) 若入射光的频率均大于一给定金属的红限，则该金属分别受到不同频率、强度相等的光照射时，单位时间释出的光电子数一定相等； (4) 若入射光的频率均大于一给定金属的红限，则当入射光频率不变而强度增大一倍时，该金属的饱和光电流强度也增大一倍。以上说法正确的是（ (A) (1)，(2)，(3)； (C) (2)，(3)；） (B) (2)，(3)，(4)； (D) (2)，(4)。

北京科技大学2010-2011学年第一学期高等数学AI期末A卷及答案

北京科技大学2010-2011学年第一学期高等数学A （I ）期末（A ）试卷院（系）________ 班级________学号________姓名________考场_______说明：1、要求正确的写出主要的计算或推倒过程，过程有错或只写答案者不得分；2、考场、学院、班级、学号、姓名均需全写，不写全的试卷为废卷；3、涂改学号以及姓名的试卷为废卷；4、请在试卷上作答，在其它纸上解答一律无效. 1.曲线{(1)0t 10y x t t e y +-=++=在t=0处的切线方程为。

2.若f （t ）=21lim (1)tx x t x→∞+，则()f t '=。

3.已知2(tan )sec f x x '=，则f （x ）= 。

4.当c=时，曲线2y x =和3(0)y cx c =>所围成的图形的面积为23。

5.幂级数21n nn e x n∞=∑的收敛半径为。

一、填空题（每小题4分，共24分）0ζ>，当(,)x a a ζζ∈-+时必有（）（A ）()(()())0x a f x f a --≥（B ）()(()())0x a f x f a --≤（C ）2()()0()()f t f x x a t x -≥≠-（D ）2()()0()()f t f x x a t x -≤≠-7.设函数f （x ）有原函数xlnx ，则()xf x dx =⎰（）（A ）211(ln )24x x c ++（B ）211(ln )42x x c ++（C ）211(ln )42x x c-+（D ）211(ln )24x x c-+8.设15sin 00sin (),()(1)xx t ta x dt x t dt tβ==+⎰⎰，则当0x →时，()()a x x β是的（）（A ）高阶无穷小（B ）低阶无穷小（C ）同阶但不等价的无穷小（D ）等价无穷小9.设10(1,2,),n nn a n L a ∞=>=∑且收敛，常数,2πλ∈（0，，则级数n1-1tan )nn n a n λ∞=∑（）（（）（A ）绝对收敛（B ）条件收敛（C ）发散（D ）收敛性与λ有关10.曲线1nxy xe =（）（A ）仅有水平渐近线（B ）仅有铅直渐近线（C ）无渐近线（D ）既有铅直渐近线又有斜渐近线11.求极限22201lim (1)x t x x t e dt x -→+∞+⎰. 12.求22ln xxedx +⎰.13.求sin 2x xdx ⎰.14.求。

（完整版）北科大材料力学答案版.doc

（完整版）北科大材料力学答案版.doc自觉遵装守订考试线规则内，诚不信考得试，答绝不题作弊北京科技大学 2012--2013 学年第 2 学期工程力学 AII 试卷（ A ）院 (系) 班级学号姓名试卷卷面成绩占课平时成绩课程考程考占核成绩题号一二三四五六小计核成20%得分得分一、判断题（20分，每题2分，将“√”或者“X”填入题后括号内。

）1. 材料力学主要研究强度、刚度和稳定性问题。

（√）2. 矩形截面梁由剪力引起的剪应力在中性层为0,上下边缘处最大。

（ X ）3. 结构刚度越大 ,变形越小 ,也越不容易失稳。

（√）4. 塑性材料和脆性材料的失效破坏机理是一样的。

（ X ）5. 单位载荷法等能量方法可以直接用于求梁结构中的最大应力。

（ X ）6. 电测法的基本原理是将结构变形引起电阻丝长度变化,进而导致电阻等电学物理量的变化 ,由电学量的变化反推可得到结构的变形信息。

（√）7. 低碳钢扭转破坏试验后其断口平面与轴线垂直。

（√）8.测低碳钢的弹性模量与泊松比时在其上下表面各贴一个应变片,其主要考虑是得到双倍的应变值 ,因为越大的物理量测量精度一般越高。

（ X ）9. 铸铁试件的拉伸和扭转失效 ,主要原因都是最大剪应力超过了许用值。

（ X ）10. 对于主要受挤压的结构件,允许结构中出现部分的塑性变形。

（√）得分二、如图所示外伸梁，B为固定铰，C为移动铰，A端受集中力P=10 kN，B点受一集中力偶 M=40 kNm，HD 段受均布力 q=10 kN/m ，AB 、 BH、HC 和 CD 各段的长度均为 L=1 m，试作出梁的弯矩图和剪力图。

（20 分）qMA BDHPN B和C解：解除 B 点和 C 点约束，分别代之以约束反力 CN ，由M B 0，即PL M 2qL 2L N C 2LN C M PL 4qL245 kN (2 分)2L由M C 0，即3PL M N B2LN B M 3PL(2 分)35 kN2L2 分，一共 16 分，加上支反力 4 分，共计 20 分。

2011-2012(1北科大校内竞赛试题及答案

大学物理竞赛试卷
第 7 页共 7 页
l
④。
试判断下列结论是包含于或等效于哪一个麦克斯韦方程式的，将你确定的方程式用代号填在相应结论后的空白处。 (1) 变化的磁场一定伴随有电场：_____________________； (2) 磁感应线是无头无尾的： ________________________； (3) 电荷总伴随有电场： ____________ __ _______。
订线内不得答题
∫
v2
v1
1 mv 2 Nf (v)dv 的物理意义是（ 2
）
（A）速率为 v2 的各分子的总平动动能与速率为 v1 的各分子的总平动动能之差；（B）速率为 v2 的各分子的总平动动能与速率为 v1 的各分子的总平动动能之和；（C）速率处在速率间隔 v1—v2 区间内的分子的平均平动动能；（D）速率处在速率间隔 v1—v2 区间内的分子平动动能之和。 2、如图 1 所示，若在某过程中，一定量的理想气体的内能 E 随压强 P 的变化关系为一直线（其延长线过 E—P 图的原点），则该过程为（（A）等温过程； 3、如图 2 所示，一定量的理想气体，分别由初态 a 经①到达 b 和由初态 a′经②到达 b，则关于过程①所吸
6、II
7、
B2 − B1 2μ 0
2
8、
μ0 I π r 2ω
2aR
sin ωt
9、
2a0 + g 3
10、 ②，③，①
三、计算题 1.（1）利用角动量守恒： mvR =
1 2mv ； MR 2ω + mR 2ω 得： ω = (2m + M ) R 2 R M 2 （2） M f = ∫ μ g rd m = ∫ μ gr 2 π rdr = μ M g R 2 0 πR 3 3 mv dω 由 M f ⋅ Δ t = J ⋅ Δω 或 M = J 得： Δt = 。 μM g 2 dt

2010-2011(1)校内竞赛试题及答案

2
2
4R
（1 分）
(ΔE ) = 3 RΔT = 3 A
He 2
8
（2 分）
（2）气缸绝热，
dQI + dQII =ν CI dT +ν CII dT = 0
பைடு நூலகம்
（1 分）
而氮气经历等体过程
CII
= CII ,V
=
5 2
R
，因此
CI
=−5R 2
（3）氦气的热量变化 dQI
=ν CI dT
=−
5 RdT 2
7．下列说法正确的是（A）有电流就有磁场，没有电流就一定没有磁场；（B）变化着的磁场所产生的电场，一定随时间而变化；（C）变化着的电场所产生的磁场，一定随时间而变化；（D）变化着的电场所产生的磁场，不一定随时间而变化。
8．在静电场中，下列说法正确的是（A）带正电荷的导体，其电势一定是正值；（B）等势面上各点的场强一定相等；（C）一个孤立的带电导体，表面的曲率半径愈大处，电荷密度愈小；（D）在导体表面附近处的场强，是由该表面上的电荷产生的，与空间其它地方的电
a× ×
N
υ ×G
b×
B
×
图4
得分二、填空题（30 分）
1．在标准状态下, 体积比为 V1 = 1 的氧气和氦气（均视为刚性分子理想气 V2 2
体）相混合, 则其混合气体中氧气和氦气的内能比为_________。
2．地面上 A、B 两点相距 100m，一短跑选手由 A 跑到 B 历时 10s。一宇宙飞船相对
此电动势既为 a、b 两点间电动势大小。
（3 分）
（2）ε
>
0
G ，说明电动势的方向与 v

2011-2012-2-AII期中考试及答案

B E C
20. 图 8 为一种声波干涉仪，声波从入口 E 进入仪器，分 BC 两路 A 在管中传播至喇叭口 A 汇合传出，弯管 C 可以移动以改变管路长图8 度，当它渐渐移动时从喇叭口发出的声音周期性地增强或减弱，设 C 管每移动 10 cm，声音减弱一次，则该声波的频率为（空气中声速为 340 m/s） ________________________。
北京科技大学 2011–2012 学年第二学期
大学物理 AII
院(系) 班级学号
期中试卷
姓名
成绩
自觉遵装守考订试线规则内，诚不信考得试，答绝不题作弊
1．一定量的理想气体贮于某一容器中，温度为 T，气体分子的质量为 m。根据理想气体分子模型和统计假设，分子速度在 x 方向的分量的下列平均值
c
a Va
图4
b Vb V
11．图 5 中 MN 为某理想气体的绝热曲线， ABC 是任意过程，箭头表示过程进行的方向。由此可判断：与初态 A 相比，末态 C 的熵 _________（填“增加” 、 “不变”或“减少” ）。
图5
12． 2mol 的双原子气体，在压强为 p0 下从 T1 等压加热到 T2，然后
1.7 103 Hz
20.
大学物理 AII 期中试卷
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大学物理 AII 期中试卷
第 1 页，共 3 页
5．常温常压下，一定量的某种理想气体(其分子可视为刚性分子，自由度为 i )，在等压过程中吸热为 Q，对外作功为 W，内能增加为 E ，则 W/Q=________________。
6．用总分子数 N、气体分子速率 v 和速率分布函数 f (v) 表示下面的量：速率大于 v 0 的那些分子的平均速率＝__________________________

学科竞赛试题及答案

2011—2012学年第一学期第二临床2010年级学科竞赛试题考试日期：2011年11月10 日考试时间： 100分钟考试方式：闭卷（总分：100分，共100题）考试说明：1、请将选择题答案全部填涂在答题卡上，写在试卷上一律无效。

其余试题的答案写在试卷上。

2、请在答题卡上填涂好姓名、班级、寝室号、学号。

考号为学号。

3、所有试卷不得带出考场之外，否则以作弊论处。

4、在考试结束前10分钟时，监考老师先收答题卡，考试结束时，再收试卷，并以班级为单位，按学号顺序整理好。

一、单选题（每题1分，共62分）生理1.低温、缺氧或代谢抑制剂影响细胞的Na-K+泵活动时，将导致（）A．静息电位增大，动作电位幅度减小B．静息电位减小，动作电位幅度增大C．静息电位增大，动作电位幅度增大D．静息电位减小，动作电位幅度减小E．以上都不是2.终板膜上与终板电位产生有关的离子通道是（）A．电压门控钠离子通道B．电压门控钾离子通道C．电压门控钙离子通道D．化学门控非特异性镁通道E．化学门控钠离子和钾离子通道3.局部兴奋的产生是由于（）A．刺激使细胞超级化B．膜自身去极化反应C．刺激使细胞膜轻度去极化D．刺激激活大量Na+通道E．膜自身超级化4.下列不可作为第二信使的物质有（）A．Ca+ B．cAMP C．IP3 D．DG E．调钙蛋白5．骨骼肌收缩和舒张的基本功能单位是（）A．肌原纤维B．肌小节C．肌纤维D．粗肌丝E．细肌丝6.下列哪项因素会降低骨骼肌的收缩力（）A. 增加后负荷B. 增加前负荷C. 给肾上腺素D. 缺氧E. 给咖啡因7．在局部兴奋中，不应期不明显的原因是（）A．激活的钠离子通道数量少，失活也少B．与动作电位中的钠离子通道性质不同C．阈下刺激的后作用时间短D．没有钠离子通道的再生性开放机制E．钾离子通道开放8 骨骼肌细胞外液中钠离子浓度降低使（）A．静息电位增大 B．动作电位幅度变小C．去极化加速 D．膜电位降低E．复极化加速9.血管外破坏红细胞的主要场所是（）A．肾和肝 B．淋巴结 C．肾脏 D．脾和肝 E．胸腺和骨髓10．安静时细胞膜内K+ 向膜外移动是通过（）A．主动转运B．单纯扩散C．易化扩散D．出胞E．入胞11、外源性和内源性凝血的主要区别是（）A．前者发生在体内，后者发生在体外B．前者发生在血管内，后者发生在血管外C．前者只需体内凝血因子，后者还需外加因子D．前者只需血液凝血因子，后者还需组织因子E．激活因子的途径Ⅸ不同12、血小板含量明显减少时，可导致皮肤出现出血瘀点，其原因是血小板（）A．不易粘附血管内膜B．使血管回缩出现障碍C．释放血管活性物质不足D．凝集能力下降E．不能修复和保持血管内皮物质的完整性13、哪一种血性的人不易找到合适的供血者（）A．AB型，Rh阴性B．A型，Rh阴性C．B型，Rh阳性D．AB型，Rh阳性E．O型，Rh阳性14 正常人心率超过180次/min时，心输出量减少的原因主要是哪一时相缩短（）A 快速充盈相B 减慢充盈相C 等容收缩相D 减慢射血相E 心房收缩期15异长自身调节是由于下列哪项发生了变化（）A 粗细肌丝重叠状态B 横桥ATP酶活性C 胞浆游离Ca2+浓度D 肌钙蛋白对Ca2+亲合力E 肌动蛋白活性16 钙通道阻断剂异搏定对浦肯野氏细胞动作电位的影响是（）A 0期除极幅度降低B 0期除极速度减慢C 1期复极时程缩短D 2期复极时程缩短E 3期复极时程缩短17 去甲肾上腺素使浦肯野细胞自律性增高是通过（）A 最大复极电位降低B 电位水平下降C If电流增强D 膜对K+通透性降低E Isi电流增大18 心肌收缩力加强导致静脉回心血量增加的机制是（）A 动脉血压升高B 血流速度快C 收缩期室内压较低D 舒张期室内压较低E 静脉血流阻力下降19 心肌低氧引起冠脉舒张的主要因素是（）A. 氢离子B. 组胺C. 腺苷D. 前列腺素E. 乳酸20 有甲、乙二患者，甲患者左心室舒张末期容积为140ml，收缩末期容积为56ml；乙患者左室舒张末期容积为160ml，收缩末期容积为64ml，两患者的射血分数（）A 相等B 甲患者高于乙患者C 乙患者高于甲患者D 无法判断E 均低于正常21 两患者均为青年男性，其中甲患者身高1.5m、体重50kg ,体表面积1.4m2、安静时每分输出量4.2L；乙患者身高1.6 m,体重68kg、体表面积1.7m2、安静时每分输出量5.1L 两患者的心指数（）A 甲患者优于乙患者B 乙患者优于甲患者C 相同D 均高于正常E 均低于正常22 某患者出现颈静脉怒张，肝脏肿大和双下肢水肿，最可能的心血管疾病是（）A. 左心衰B. 右心衰C. 肺水肿D. 高血压E. 中心静脉压降低23 某患者由平卧位突然站立，静脉回心血量减少，每搏输出量、动脉血压降低。

北科大2011-2012学年度第二学期高等数学期中考试试题答案

北京科技大学2011——2012学年第二学期高等数学AII 期中试卷答案一、填空题（本题共36分，每小题4分）1. 361a π; 2. 3)3,12(=-A k j i 38-+， 3.z y d f y x d f du 21'+'=dz f z y dy f y x f z dx f y 22122111'-⎪⎪⎭⎫ ⎝⎛'-'+'= ; 4. ⎰-x d f x 02)()(21ζζζ; 5. 61; 6. 40; 7.⎪⎭⎫ ⎝⎛'''r r f z r r f y rr f x )(,)(,)(; 8.π; 9.40x y z +-=. 二、选择题（本题共36分，每小题4分）10. C; 11. B; 12. A; 13. D; 14. A; 15. B; 16. D; 17. C; 18. D三、解答题(本题共2小题,每题9分，满分18分)19.在x x x u =)2,(两边对x 求偏导数，有12(,2)2(,2)1u x x u x x ''+=，两边再对x 求偏导数，则()11122122(,2)2(,2)2(,2)2(,2)0u x x u x x u x x u x x ''''''''+++=，又因为),(y x u 具有二阶连续偏导数，且22220u u x y∂∂-=∂∂，所以 (*)0451211=''+''u u ， -----------5分再在21)2,(x x x u ='两边x 求偏导数，有x x x u x x u 2)2,(2)2,(1211=''+''，故由(*)式有 x x x u x x x u x x u 35)2,(,34)2,()2,(122211=''-=''=''. ----------9分 20. 设椭圆上任意点的坐标为),,(z y x ，令 22222(,,,,)()(1)F x y z x y z z x y x y z λμλμ=+++--+++- -----3分由2222022020010x y z F x x F y y F z F z x y F x y z λμλμλμλμ⎧=-+=⎪=-+=⎪⎪=++=⎨⎪=--=⎪⎪=++-=⎩得两点11222⎛-+-+- ⎝，11222⎛----+ ⎝， ------6分由题意所求最值一定存在，且一定在此两点取得，故所求最长距离与最短距离分别为359+和35-9. -----9分四、证明题(本题共2小题,每题5分，满分10分) 21. dr r r f dr r r f d d t F t t 200222020)(4sin )()(⎰⎰⎰⎰==πϕϕθππ, -----3分πππ54)0(54)(4lim )(lim 5202050='==⎰++→→f t drr r f t t F t t t --------5分 22. 因为()0)()(2≥-y f x f ， --------- 2分所以在b y a b x a D ≤≤≤≤,:上，有dxdy y f y f x f x f d y f x f D D ))()()(2)(())()((022⎰⎰⎰⎰+-=-≤σ，即有 ⎰⎰⎰⎰⎰⎰⎰⎰⎪⎭⎫ ⎝⎛--=+-≤ba b a b a b a b a b a b a ba dx x f dx x f ab dy y f dx dy y f dx x f dy dx x f 2)(2)()(2)()()(2)(0222 ⎰⎰-≤⎪⎭⎫ ⎝⎛b a b a dx x f a b dx x f )()()(22 ----------5分。

北科大2011大学物理试卷

北京科技大学 2011-2012学年第一学期大学物理B 试卷（A ）院(系) 班级学号姓名一、选择题（30分）1．质点做曲线运动，r 表示位置矢量，s 表示路程，v 表示速度，a表示加速度，τa 表示切向加速度。

以下表达式正确的是（）。

（A ）v dt ds =；（B ）v dtdr=；（C ）a dt dv =；（D ）τa dtv d = 。

2．质量为0.10kg 的质点，由静止开始沿曲线j i t r10313+=（SI ）运动，则在t =0到t =2s 时间内，作用在该质点上的合外力所做的功为（）。

（A ）5/4 J ；（B ）0.80 J ；（C ）40 J ；（D ）75/4 J 。

3．一平面简谐波在弹性媒质中传播时，下述各结论正确的是（）。

（A ）媒质质元的振动动能增大时，其弹性势能减小，总机械能守恒；（B ）媒质质元的振动动能和弹性势能都做周期性变化，但二者的相位不相同；（C ）媒质质元的振动动能和弹性势能的相位在任一时刻都相同，但二者的数值不相等；装订线内不得答题自觉遵守考试规则，诚信考试，绝不作弊4．厚度为e 的平行膜把空间分成三部分。

波长为λ的光垂直入射，若321n n n 〈〈，则满足（）＝λk ±，反射光加强。

（A ）e n 2；（B ）e n 22; (C) 22λ+e n ;(D) 222λ+e n5．有两条长直载流导线平行放置，电流强度分别为1I 和2I ，L 是空间一闭合曲线，1I 在L 内，2I 在L 外，P 是L 上一点。

今将2I 在L 外向1I 移近时，则有（）。

（A ）⎰⋅Ll d B与P B 同时改变；（B ）⎰⋅Ll d B改变P B 不变；（C ）⎰⋅Ll d B与P B 都不改变；(D) ⎰⋅Ll d B不变P B 改变。

6．在真空中有半径为R 的一根半圆形导线，流过的电流为I ，则圆心处的磁感应强度为( )。

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