ELC口试问题
英语口语考试常见题目及应答
1.Would you like to say something about test-oriented education vs quality-oriented education?(你是否想谈谈应试教育与素质教育？)Test-oriented education has caused a great deal of tragedies. Students are treated as “Exam machines” rather than alive human beings with feeli ng. Quality-oriented education may offer an effective education.2.Some foreigners find that the practice of “one-child” policy goes against the basic principles of human rights .Do you think it’s a good policy? Why or why not? (一些外国人发现“独生子女”政策违反人权主义.你认为这是一项好政策吗?为什么或者为什么不吗?I think it’s a good policy in China. In my opinion, the China’s one child policy is a population control success. Many people know that China is a overpopulation country and it is the most people country in the world. this policy is the society care and economy care for the people is lack in China.3.Which one is more important: acquiring academic achievements or seeking work experience?(哪一个更重要:获得学术成就或者寻找工作经验?)In my opinion, acquiring academic achievements is indispensable part in my life, because I enrich my knowledge, learn to do research. But seeking work experience is more important for me. I think I should put my knowledge into my work.4.What do you think of blind date? （你是怎样理解一见钟情的）They don’t know each other, but they have the sam e goal—in order to get married. That is funny and uncredible . Maybe it is a chance to make a friend or become a stranger.5.What’s your opinion about human cloning? (对于无性繁殖你有什么看法！？)I am against the human cloning, because we are suppose to be unique and different in each way. It isn't natural and i also do not like the fact about test tube babies.6.Could you explain the saying: In wine there is truth? （你能解释格言: 酒后吐真言）In wine there is truth. （酒后吐真言。
二职航空英语口语面试常见问题
二职航空英语口语面试常见问题How do you handle failure?How do you handle change?When you are in charge, how do you motivate people? Describe a time when you resolved a conflict?Can you work under pressure?What is your greatest strength?What is your greatest weakness?What have you done to correct your weaknesses?Have you ever failed?What is your biggest failure?How do you handle conflict?Previous EmploymentWhat is the hardest thing you ever did in your current job? Why have you held so many jobs?Do you consider yourself a loyal employee?What did you like about your last job?What did you dislike about your last job?What was your favorite job?What was your least favorite job?What have you learned from previous jobs?How long will you stay with our airline?What would your coworkers say about you?What would your previous supervisors say about you?What were the people like at your last company?What did you dislike about your last employer?If you could change one thing about your last employer, what would it be?Were you satisfied with your performance at your last job?Was your previous employer satisfied with your performance?Have you ever been fired?If so, why were you fired?Have you ever been asked to resign from another job?What will your references say?Can we check your references?How many sick days did you take last year?Is this typical?Personality and MotivationDo you consider yourself a success?Were you ever under a great deal of pressure?What kinds of decisions are most difficult for you?Why has it taken you so long to find a job?Why do you want to be a flight attendant?What part of being a flight attendant interests you most?What kind of contributions will you make to our airline?Where else are you interviewing?Have you applied to other airlines?When are you available to start?What are your outstanding qualities?What interests you most about being a flight attendant?What can you do for us that others can''''''''''''''''t?Describe a difficult problem you''''''''''''''''ve dealt with.How important is appearance?What do you think will be the biggest challenge of being a flight attendant?What is the best part of being a flight attendant?Do you have any natural talent or skill, something that comes easy to you?What do you like to do in your spare time?How would you handle an abrasive Captain or coworker?Have you ever been described as stubborn or hardheaded? By whom?Do you ever freeze in social situations?Have you ever worked with someone who talked too much? How did you handle it?Are you skilled at sizing people up?Have you ever been part of a problem?Have you ever had to support the directives of higher management, even when you disagreed with it?Have you ever lied?Have you ever broken a law?Have you ever stolen something?Have you ever found a work policy or rule to be distasteful? How did you handle it?Have you ever been tempted to break a work rule or policy? What did you do?Why do you want to work for our airline?What kind of experience do you have?Are you willing to be based wherever the company sends you?What would you like to be doing ten years from now?Why should we hire you?What are your qualifications?What is your biggest accomplishment?What are your career goals?How does a flight attendant job fit into your career goals?What personal characteristic best describes you. Do you prefer to work alone or with others?Do you consider yourself a team player?Describe your team style.Are you self motivated?What motivates you?Describe your relationship with peers.What kind of people do you prefer to work with? Describe your personality?How do you handle criticism?Were you ever unfairly criticized?SkillsDo you read, write and/or speak a foreign language? Are you willing to learn a foreign language?Are you a leader or a follower?What have you learned from your previous jobs? What kind of employee are you?What was your favorite subject in school?What was your least favorite subject in school?Tell us about your leadership skills.What was your major success as a leader?What was your major failure as a leader?What do you think are the most important components of a practical leadership philosophy?Whose leadership qualities have you most respected?Have you incorporated his/her leadership qualities?Have you ever had an unexpected leadership role? How did it work out?What are your assets?Whom do you most admire?Other QuestionsWhat bases does our airline have? What type of aircraft?Who is the president of our company?How long has our airline been in existence?How do you feel about the airline industry?How do you feel about being away from home frequently?How do you feel about relocating?How do you feel about unions?What do you feel is the role of unions?Why do you want to leave your previous employer?Will we find anything on our background search thatyou''''''''''''''''d like to discuss now?Is there anything you would like to discuss?Do you have any questions?。
英语口语面试常见问题及解答
英语口语面试常见问题及解答(总6页)--本页仅作为文档封面，使用时请直接删除即可----内页可以根据需求调整合适字体及大小--is your strength and weakness? 优缺点My greatest weakness is that I value leisure time spent with my family and therefore I treasure my weekends and free time in the evenings. My greatest strength is my commitment to work. I strive for excellence and always try to do my best.did you leave your last job你为什么离职呢The job was too busy that I have no time to write my thesis. I thought it is more important to finish my thesis.do you think you are worth to us(你怎么认为你对我们有价值呢)I have finished three new projects, and I am sure I can apply my experience to this position. I feel I can make some positive contributions to your company in the future.make you think you would be a success in this position (你如何知道你能胜任这份工作）My graduate school training combined with my internship should qualify me for this particular job. I am sure I will be successful. (我在研究所的训练，加上实习工作，使我适合这份工作。
出口成章英文面试中的个常见问题及回答技巧
出口成章英文面试中的个常见问题及回答技巧In the competitive job market, face-to-face interviews remain an essential step towards securing a job, especially for those seeking employment opportunities abroad. English proficiency is often a key requirement for many positions, leading to interviews conducted entirely in English. To help candidates navigate these interviews successfully, this article will address some common questions that are frequently asked during English interviews and suggest effective strategies for providing responses. By being well-prepared and practicing these techniques, job seekers can confidently showcase their skills, experience, and suitability for the role.Question 1: "Tell me about yourself."This question serves as an icebreaker and an opportunity for candidates to provide an overview of their background. When responding, it is important to focus on relevant details such as education, professional experience, and key accomplishments. A brief summary highlighting skills, strengths, and reasons for pursuing the specific job can also help demonstrate enthusiasm and motivation.Question 2: "Why are you interested in this position?"To answer this question, candidates should explain why they find the position appealing and align their skills and experiences with the job requirements. Researching the company and understanding its values, mission, and culture can enable candidates to tailor their response effectively.By highlighting how their goals and aspirations align with the organization, candidates can showcase their genuine interest and enthusiasm.Question 3: "What are your strengths and weaknesses?"When discussing strengths, candidates should focus on qualities that are highly desirable in the job role. Providing examples of how these strengths have led to previous successes can strengthen their response. As for weaknesses, it is essential to mention areas for improvement while emphasizing efforts made to overcome them. Sharing strategies, such as seeking additional training or mentorship, displays proactiveness and a willingness to grow professionally.Question 4: "Can you provide an example of a challenging situation at work and how you handled it?"To effectively answer this question, candidates should select a relevant example from their professional experience. Using the STAR method (Situation, Task, Action, Result), job seekers can describe the context of the situation, explain their role and actions taken, and highlight the positive outcome or lessons learned. This approach demonstrates problem-solving skills, adaptability, and the ability to handle challenges.Question 5: "How do you handle working in a team?"For this question, candidates should emphasize their ability to collaborate and communicate effectively with team members. Providing specific examples of past experiences where they successfully worked in a team, resolved conflicts, or contributed to team achievements can impress the interviewer. Demonstrating attributes such as flexibility, active listening,and leadership skills can showcase their ability to work harmoniously with others.Question 6: "Where do you see yourself in five years?"When responding to this question, candidates should demonstrate ambition and commitment while aligning their goals with the company's growth potential. Describing specific career milestones and a desire for professional development shows enthusiasm and long-term dedication. However, being flexible and open to opportunities within the organization can also indicate adaptability and a willingness to contribute to its success.Conclusion:By preparing responses to these common interview questions and delivering them with confidence, job seekers can enhance their chances of success in English interviews. Remember to practice proper pronunciation, maintain good eye contact, and employ appropriate body language to convey professionalism and engagement. Each interview is a valuable opportunity to demonstrate skills, experience, and cultural fit, and by being well-prepared, candidates can present themselves as strong contenders for their desired role.。
雅思口语考试考官最爱问的170个经典问题四
雅思口语考试考官最爱问的170个经典问题(四)121. What do you intend to do after you finish studying?122. What will be your main problem when you are study in a foreign country?123. What problem can you foresee in the future when you come back to China?124. Will there be any adjustment problems in your life when you come back to China? If so, what are they?125. Will you have to make any changes in your work/life when you come back to China?126. Do you think there will be a gap between your knowledge gained in China and the level of knowledge you are going to encounter on arrival? If so, what will it be?127. What do you think of the future of China keeps an open policy?128. What do you regard as the most significant events in your country’s recent history?129. Are there any special places you want to see in Canada? What are they?130. What do you especially want to do in Canada?131. How do you like your life in ABC University?132. What do you think of the training in the university?133. In what way do you think university training is helpful or falls short?134. What aspect of English do you find the most difficult?135. Do you find American English easier to understand than Britain English?136. What sports are played in your country?137. Could you describe the traditional architecture of your country?138. What role dose religion play in everyday life in your country?139. What would you regard as the most significant events in your country"s recent history?140. How aware do you think people are nowadays about environmental issues?141. Could you tell me why you chose to study at the university of ABC?142. What role dose tourism play in your country"s economy?143. How serious is unemployment in your country?144. In your opinion, what are the most serious problems associated with modern life?145. What do you think have been the most important changes in your field over the past 5 years?146. What are you going to major in ?147. Are you going to do your own cooking when you are at university?148. Some local students feel that overseas students get preferential treatment. What is your opinion?149. Do you think you will be able to cope with the English-language demands of your intended program?150. What do you think are the main causes of road accidents?151. Do you think the government is doing enough to prevent road accidents?152. As there are more and more private cars, what do you think the governmentshould do in order to encourage citizens to use public transport?153. How do you see yourself in ten years" time?154. Have you ever thought to have your own business?155. What business do you hope to have?156. Do you know about any policies about opening a business abroad?157. What are your plans for your future?158. Why do you think there are more and more people leaving to immigrate to other countries?159. Is it good for China that so many people are going to other countries?160. Will your life change a lot after you immigrate to ABC?161. What will you do if you are ill abroad?162. Do you know what to do in case of emergency?163. What will do if you cannot find a job in ABC?164. Why do you want to immigrate to ABC?165. What will you do after the IELTS test?166. What will do if you fail the IELTS test?167. What"s your dream job?168. How long have you been learning English?169. What troubles you most at the moment?170. Does your family support your decision on going ABC? What help do they offer? 【。
2021年国际学校英语口语面试问题
The sacred work is in everyone's daily affairs, and the ideal future lies in starting bit by bit.勤学乐观天天向上（WORD文档/A4打印/可编辑/页眉可删）国际学校英语口语面试问题1、对于职场新手（），常见英语面试问题如下：Tell me about yourself.英语自我介绍。
Why should I hire you?为什么要聘你？What are your strengths and weaknesses?你有哪些优点？又有哪些缺点？Why do you want to work at our company?为什么选择我们公司？What is the difference between confidence and over confidence? 自信和盲目自信的区别是什么？What is the difference between hard work and smart work? 努力工作和明智工作的区别是什么？How do you feel about working nights and weekends?你愿意加班吗？Can you work under pressure?你能在压力下工作吗？Are you willing to relocate or travel?你愿意经常出差吗？What are your goals?你的目标是什么？What motivates you to do good job? 你的工作动力是什么?What makes you angry? 你会因为什么而生气？Give me an example of your creativity. 你的创新能力如何呢？举例说明。
How long would you expect to work for us if hired? 如果你应聘上了的话，你准备在我们公司待多久Are not you overqualified for this position? 对于这个职位，你的能力完全是绰绰有余Describe your ideal company, location and job. 能说说你理想的公司、工作地点以及工作吗？What are your career options right now? 你现在的职业选择是什么？Explain how would be an asset to this organization? 怎样才能为组织出力呢？What are your outside interests? 你的外部利益是什么？Would you lie for the company? 你会对公司说谎吗？Who has inspired you in your life and why? 在你的生活中谁给你激励最多，为什么？What was the toughest decision you ever had to make? 你曾经做过的最糟糕的决定是什么？Have you considered starting your own business? 你有没有想过自己开公司？How do you define success and how do you measure up to your own definition? 你怎么理解成功，你觉得自己成功吗？If you won $10 million lottery, would you still work? 如果你得了100万彩票，你还愿意工作吗?Tell me something about our company. 你了解我们公司多少呢？How much salary do you expect? 你的预期薪金是多少？Where do you see yourself five years from now? 你觉得五年之后你会成为什么样的人？On a scale of one to ten, rate me as an interviewer. 总分十分的话，你觉得我作为招聘人可以得几分？Do you have any questions for me?你有什么其他问题吗？2、对于有过工作经验的人，常见英语面试问题如下：Why did you resign from your previous job? 你为什么要辞职？Why have you been out of work so long? 你为什么这么久没有工作？Why have you had so many jobs? 你为什么这么频繁地换工作？Tell me about a situation when your work was criticized. 请讲讲当你的工作受到批评时的心情。
英语口语面试常见问题解答
英语口语面试常见问题解答在英语口语面试中，面试官通常会问一些常见的问题，这些问题旨在了解你的个人情况、能力和经历。
虽然这些问题可能简单，但是你的回答可以展示你的英语口语能力和与他人沟通的能力。
在下面的文章中，我将为你解答一些常见的英语口语面试问题。
问题一：介绍一下你自己。
回答：首先，我非常感谢你给我这个机会来介绍自己。
我是一个有抱负的年轻人，对于英语学习和发展职业有着强烈的兴趣。
我在大学学习了英语专业，并且在校期间有过一些实习经验。
我喜欢与人交流，并且能够很好地适应多元化的工作环境。
我有较强的团队合作能力，并且能够独立解决问题。
我相信这些优势将使我成为一名出色的候选人。
问题二：你为什么选择应聘这个职位？回答：我选择应聘这个职位是因为我对这个行业非常热爱，并且我相信自己有能力在这个领域中取得成功。
我对你们公司的产品和服务非常了解，并且我认为我可以为公司带来价值。
此外，我也希望通过这个职位拓宽我的技能和知识，并且有机会与优秀的团队共事。
问题三：你最大的优点是什么？回答：我认为我最大的优点是我的沟通能力。
在我过去的工作经历中，我与客户和同事建立了良好的沟通和合作关系，这有助于我们高效地达成团队目标。
我善于倾听他人的观点，并能够清晰地表达自己的想法。
我相信这种能力将使我成为一名与人合作的优秀员工。
问题四：你是如何处理工作压力的？回答：当面临工作压力时，我会先冷静下来，分析问题的根源。
然后，我会制定一个明确的计划，将任务分解成更小的子任务，以便更好地管理。
此外，我会寻求帮助，与团队成员讨论，以找到最佳的解决方案。
最重要的是，我会保持积极的态度，并且相信自己能够克服困难。
问题五：你对职业发展有什么规划？回答：我对职业发展有明确的规划。
首先，我希望在目前的工作岗位上获得更多的经验和知识。
然后，我希望通过不断学习和提高自己的技能，逐渐晋升到更高的职位。
此外，我也计划参加一些与行业相关的培训和课程，以便保持竞争力并扩展自己的技能。
面试问题(C+E)
问：为什么你认为你对该行业会保持长久的兴趣？答：撇开晋升的机会不说，该行业的技术变化得如此快，所以这里有广阔的就业机会。
我尤其对多方面应用多媒体作为培训手段感兴趣。
你对该行业的发展前景有什么期望或设想？它使你不需晋升就可以获得发展吗?这家企业里什么使你最受鼓舞？你可以提供什么证据来证明你的兴趣来源于你极度的好奇——可能回到几年前的时间去找这个证据——而不是目前这些你可能放弃的一时兴致?Q:Why do you think this industry would sustain your interest over the long haul?A:The technology in the industry is changing so rapidly that I see lots of room for job enhancement regardless of promotions. I am particularly interested in the many applications for multimedia as a training tool.问：5年之内你想处于什么位置？答：我希望有机会在工厂或国内办事处工作。
我也希望通过管理一个小团体发展我的管理技能。
不要给出具体的时限或工作头衔。
谈你喜欢的东西，你天生的技能，实际的问题和在你所选的领域或行业里你希望有什么机会，你希望从那些经验中学点什么。
不要谈论你在那些与你所应聘的工作无关的领域或行业里的目标。
这是听起来很明显的道理，但是很多求职者会犯这个错误。
不经意间你就表现出了对当前的领域或行业缺乏真正的兴趣。
不用说，一失言马上就会把你从进一步的考虑中淘汰掉。
Q: Where do you want to be in five years?A: I'd like to have the opportunity to work in a plant as well as at the home office.I also hope to develop my management skills,perhaps by managing a small staff.问：描述你的理想职业。
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各章复习重点第一章0001：说明触点工作一个循环时所经历的四个工作阶段的情况（１）闭合状态－应保证被控电路电流顺利通过；（２）断开状态－应保证被控电路在任何环境条件下都不能形成通路；（３）闭合过程－由断开状态到闭合状态的过渡；（４）开断过程－由闭合状态到断开状态的过渡。
0002：开关电器的触点在控制直流电路通断的一个循环内，触点之间可能发生哪些物理现象?间有接触电阻存在，在开断过程中触点间会产生金属桥以及气体导电。
在断开状态时触点间会因绝缘不足而导致击穿放电。
0003：两个导体相互接触时为什么会产生接触电阻？产生接触电阻的原因有两个方面：①由于接触面的凹凸不平，使导体的实际接触面积减小,因而流过接触面的电流要发生严重的收缩现象而产生收缩电阻； ②在接触表面生成导电不良的膜而产生膜电阻。
0004：影响接触电阻的因素有哪些？①接触形式；②接触压力；③触点材料性质；④触点表面的加工情况；⑤采用密封触点结构。
0005：有一电阻为Rd的铜棒，将它截断后又用压力Ｐ把它压紧在一起。
（假设铜棒的长度不变）试问该铜棒的电阻值将如何变化？为什么？铜棒的电阻在截断后要比截断前增大。
因为截断后又压紧在一起的两截铜棒的接触面上不可避免地存在着接触电阻。
而接触电阻通常是由于接触面凹凸不平引起的收缩电阻和接触0006：某一开关电器的触点是密封的，既看不到也摸不着，现发现触点的接触电阻偏大。
如何在不损坏触点的条件下，使接触电阻有所减小？适当提高加在触点两端的电压，使电场强度增大到膜的击穿强度，表面膜被击穿。
击穿0007：增加相互接触的触点上的压力为什么能够减小接触电阻？增大触点上的压力可以增加接触面上接触点的数目，使收缩电阻减小。
增大触点压力还能压碎表面膜，使膜电阻得到抑制。
0008：采用点接触和面接触两种接触形式时，对接触电阻有何影响？对收缩电阻的影响，一般说来面接触的接触点最多，收缩电阻最小；而点接触的收缩电阻最大。
对膜电阻的影响，一般说来在一定压力下点接触的压强最大，容易破坏接触面的表面膜层，使膜电阻减小，而面接触的膜电阻较大。
0009：航空接触器的触点部分都要加装触点弹簧（或称缓冲弹簧），其目的是什么？接触器的触点在闭合过程中由于碰撞和电动斥力的作用会使触点发生弹跳，对被控制电路和触点本身造成危害。
为此加装触点弹簧使触点在闭合过程中实现“柔性碰撞”，由此来减少或消除触点的弹跳。
0010：在飞机上用于控制电路通断的开关电器的触点上所发生的气体导电现象有什么危害？ 使电路的通断界限弄得模糊不清，使电器失去控制电路的能力；气体放电的高温会造成触点磨损和熔焊等，直接影响开关电器的电寿命；触点间隙上的火花放电会产生虚假高频信号，对飞机的电子设备和无线电产生干扰。
过大的放电电流还会引起火灾等严重的事故。
011：触点之间发生气体放电时，说明表面发射和空间游离有什么不同？表面发射是触点表面在某些情况下能够发射电子进入触点间隙之中；而空间游离是触点间隙中的气体自身由绝缘状态变成导电状态。
（不是由外界向放电间隙的气体中送入带电粒子）0012：电极表面发射电子的原因有哪几种？①热电子发射，电极表面高温而使自由电子获得很高的动能，逸出电极表面；②强场发射，金属电极表面高电场强度（大于106伏／厘米），使金属表面的自由电子可能在常温下逸出而成为空间的带电粒子；③光发射，各种光线照射到金属电极表面引起电子从金属表面0013：明消游离方式之一的复合是什么意思？采用什么方法可促进复合过程的进行？游离气体中两个带异性电荷的粒子相遇后相互作用而失去电荷的现象称为复合。
降低温度和增高气压可以促进复合过程的进行。
0014：开关电器的触点在开断电路时为什么会发生液桥现象？当触点开始分离前，触点间的压力逐淅减小，使接触电阻逐淅增大。
由此触点上的电能损耗增大而使触点温度不断升高。
当温度上升到触点金属熔点之后，金属局部熔化，桥接在两触点之间，成为电流通道的液桥。
0015：控制直流电路的开关触点之间的金属桥断裂后，可能出现哪些放电现象？可能出现三种放电现象，即①触点间直接生成电弧；②触点间隙被击穿而发生火花放电；③在金属液桥断裂的瞬间由强场发射引起的短弧放电。
0016：触点之间的金属桥断裂后直接生成电弧放电的条件是什么？触点断开前电路里的电流大于燃弧电流，触点断开后加在触点间的电压大于燃弧电压。
0017：开关触点在开断直流电路时，当金属桥断裂后直接生成了电弧，此时电弧中的带电粒子是如何产生的？①由于高温金属蒸气的热游离，使间隙中出现了大量的带电粒子。
②在金属桥断裂的瞬间，触点间隙是10-5—10-6 厘米时，间隙中电场强度极高，造成强场发射。
由此又引起其它形式的游离，0018：为什么降低电弧表面的温度或增高气体压力能使电弧很快熄灭？减低电弧表面温度可促进电弧中心的带电粒子向电弧周围扩散并冷却而复合成中性粒子。
增高气压使带电粒子自由行程变短，加速复合过程的进行，因此使得扩散和复合都得到增强，使电弧中带电粒子的数目快速减少，从而电弧很快熄灭。
0019：气体的碰撞游离是如何发生的？气体中原有的少数带电粒子在电场作用下被加速而具有较大动能。
这种具有较大动能的带电粒子在运动中不断与中性气体粒子相碰撞并将动能传递给中性粒子，使中性粒子游离成带电粒子。
0020：现代飞机的直流电源电压只有２８伏，为什么控制电路的触点断开时会在触点间出现高达２７０－３３０伏的瞬时电压？由于电路中不可避免地有电感存在。
当触点断开时，流过电感的电流突然减小为零，使电流变化率达到很大值。
因而在电感上产生很高的自感电势，它与电源电压正向串联以后，0021：开关电器的触点在开断直流电路时，在液桥断裂后产生火花放电的条件是什么？触点断开以前，电路的电流小于燃弧电流，而在触点断开以后，在触点间出现高于270－330伏的高压而将触点间隙击穿时，便产生火花放电。
0022：控制直流电路的开关触点间所产生的火花放电与电弧放电有什么不同？放电的条件不同。
若被开断电路的电流大于燃弧电流，断开后加在触点间的电压大于燃弧电压时，不经过触点的击穿便直接生成电弧。
若被开断电路的电流小于燃弧电流，断开后加在触点间的电压高于触点间隙的击穿电压（270－330伏）并击穿触点间隙时，便产生火花0023：为什么开断直流电路时所产生的火花放电是一种忽通忽断的不稳定放电现象？由于触点间隙具有电容效应，当触点刚分离时，电路电感上的自感电势给触点充电并达到触点间隙的击穿电压时击穿触点间隙，释放触点上的电荷。
当放电终止时，自感电势再次对触点充电，电压再次升高，间隙再次被击穿，但由于间隙的不断增大，再次击穿电压一次0024：在开关电器的触点间隙上产生的火花放电有什么害处？火花放电通常在较高气压的条件下生成，电流密度比较高，并伴有高温，因而会引起触点烧损；火花放电还会在线路中产生虚假的高频信号，对电子设备和无线电通信造成干扰。
0025：为什么直流电弧具有电流增加时电压下降的特性？因为电弧电流越大，电弧温度就越高，气体的热游离程度也就越高，弧柱电阻越小，所以电弧电压随电流增大反而下降。
0026：直流电弧的静态伏安特性有哪两个特点？①当弧长不变时，电弧电压随电弧电流的增大而减小；②在同样电流下，当电弧长度增大时，电弧电压升高，即伏安特性曲线上移。
0027：如图Ｅ１－１所示，控制直流电感负载电路的开关Ｋ的触点两端，并联一条ＲＣ串联支路来熄灭火花的原理是什么？因电容两端电压不能突变，在触点刚分离时，触点间隙的电压很低而不能击穿，也就不会产生火花放电。
当触点间的电压随电容Ｃ的充电而逐渐升到较高的电压时，触点间隙已经0028：说明如图Ｅ１－２所示的双断点触点结构的熄弧原理是什么？与单断点触点结构相比较，双断点触点上形成两个串联的电弧，在同样的条件和相同的电流下，阴极压降和阳极压降都为单断点触点的两倍。
因此，它可以在较小的间隙下获得较高伏安特性而使电弧熄灭。
0029：说明如图Ｅ１－３所示的在电感负载上并联二极管Ｄ和稳压管Ｗ来熄灭火花的原理。
选择稳压管的击穿电压UW，使U＋UW接近但又不到270－330伏。
这样可以在保证不出现火花放电的条件下，使电感上的感应电势L│di/dt│最大。
由此便可以保持尽可能高的电流衰减速度，使熄火花电路对负载动态过程的影响降到最低程度。
0030：为什么由图Ｅ１－４所示的触点结构能够熄灭电弧？这种触点结构具有自磁吹弧的能力。
被开断电流Ｉ在触点间隙处建立磁场Ｂ，其方向按右手定则决定（如图所示）。
触点间隙中的电流Ｉ在这个磁场中受到电动力Ｐ的作用，将电弧拉向触点间隙的外侧。
0031：为什么交流电弧比直流电弧容易熄灭？①因为交流电弧的熄灭主要发生在电流自然过零的时刻，熄弧作用只在于防止过零后电弧的重燃；②交流电弧在熄灭过程中，线路电感中的储能返回电源，不进入电弧，需通过电弧消耗的能量比直流电弧少。
因为直流电弧熄灭时，线路电感中的能量消耗在电弧中。
0032：交流电弧具有什么样的特性？为什么？交流电弧是一个不断熄灭又不断重燃的动态电弧。
因为交流电流的瞬时值一直在随时间变化，并且每个周期内两次通过零点。
当电流自然过零时电弧会自己熄灭，以后又重燃。
因此，交流电弧一直处于动态过程中。
0033：什么叫做触点的电磨损？触点在分合电路的过程中，在触点间隙中进行着剧烈的电和热的物理过程，伴随而产生金属液桥，电弧和火花放电等各种现象，从而引起金属材料定向转移，喷溅和气化，使触点材料损耗和变形。
这种现象即为电磨损。
0034：开关电器的触点发生磨损以后会造成什么样的后果？其主要的磨损形式是什么？触点磨损会造成触点表面破损，变形和凹凸不平，从而使触点压力，接触电阻和超行程，间隙大小等参数发生变化，甚至造成触点无法正常工作。
磨损的形式有机械、化学和电磨损三种，而电磨损是主要的磨损形式。
0035：在触点之间稳定燃烧的直流电弧沿弧长可以分为哪三个区域？各区域有什么特点？近阴极区，存在正空间电荷，形成阴极压降，具有很高的电场强度；近阳极区，存在负空间电荷，形成阳极压降，但此处的电场强度比近阴极区要低；近阴极区和近阳极区之间是弧柱区，该区内正负带电粒子数相等形成等离子体，具有金属导体的特性。
0036：如何从物理概念上来理解直流电弧的熄灭条件 Uh＞（E－Ih²R），（式中Uh为电弧电压，E为电源电势，Ih为电弧电流，R为线路电阻）。
将Uh＞（E－Ih²R）两边同乘以 Ih 可得Uh²Ih＞（E²Ih－Ih2²R）。
说明电弧消耗的功率 Uh²Ih 要大于电源输出的功率E²Ih减去线路电阻上消耗的功率I2h²R。
因此，电0037：稳定燃烧的直流电弧的阴极压降是如何形成的？阴极压降的大小与什么因素有关？在阴极前面约10-4厘米的区域内聚集了大量的正离子，形成了正空间电荷，使电位发生了急剧的改变，即存在着阴极压降。