【单选题】
熔断器的额定电流___电动机的起动电流。(单选题)
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主令电器很多,其中有___。(单选题)
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接闪线属于避雷装置中的一种,它主要用来保护___。(单选题)
A. 变配电设备
B. 房顶较大面积的建筑物
C. 高压输电线路
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测量电动机线圈对地的绝缘电阻时,摇表的“L”、“E”两个接线柱应___。(单选题)
A. “E”接在电动机出线的端子,“L”接电动机的外壳
B. “L”接在电动机出线的端子,“E”接电动机的外壳
C. 随便接,没有规定
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在一个闭合回路中,电流强度与电源电动势成正比,与电路中内电阻和外电阻之和成反比,这一定律称___。(单选题)
A. 全电路欧姆定律
B. 全电路电流定律
C. 部分电路欧姆定律
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暗装的开关及插座应有___。(单选题)
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一般电器所标或仪表所指示的交流电压、电流的数值是___。(单选题)
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我们使用的照明电压为220V,这个值是交流电的___。(单选题)
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电动机定子三相绕组与交流电源的连接叫接法,其中Y为___。(单选题)
A. 三角形接法
B. 星形接法
C. 延边三角形接法
【单选题】
一般照明场所的线路允许电压损失为额定电压的___。(单选题)
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几种线路同杆架设时,必须保证高压线路在低压线路___。(单选题)
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电磁力的大小与导体的有效长度成___。(单选题)
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感应电流的方向总是使感应电流的磁场阻碍引起感应电流的磁通的变化,这一定律称为___。(单选题)
A. 法拉第定律
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绝缘手套属于___安全用具。(单选题)
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电容器在用万用表检查时指针摆动后应该___。(单选题)
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三相对称负载接成星形时,三相总电流___。(单选题)
A. 等于零
B. 等于其中一相电流的三倍
C. 等于其中一相电流。
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在易燃、易爆危险场所,电气设备应安装___的电气设备。(单选题)
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当空气开关动作后,用手触摸其外壳,发现开关外壳较热,则动作的可能是___。(单选题)
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在电路中,开关应控制___。(单选题)
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国家标准规定凡___KW以上的电动机均采用三角形接法。(单选题)
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异步电动机在启动瞬间,转子绕组中感应的电流很大,使定子流过的启动电流也很大,约为额定电流的___倍。(单选题)
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运行中的线路的绝缘电阻每伏工作电压为___欧。(单选题)
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导线的中间接头采用铰接时,先在中间互绞___圈。(单选题)
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断路器是通过手动或电动等操作机构使断路器合闸,通过___装置使断路器自动跳闸,达到故障保护目的。(单选题)
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脑细胞对缺氧最敏感,一般缺氧超过___min就会造成不可逆转的损害导致脑死亡。(单选题)
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PE线或PEN线上除工作接地外其他接地点的再次接地称为___接地。(单选题)
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接地电阻测量仪是测量___的装置。(单选题)
【单选题】
串联电路中各电阻两端电压的关系是___。(单选题)
A. 各电阻两端电压相等
B. 阻值越小两端电压越
C. 阻值越大两端电压越高
【单选题】
《安全生产法》规定,任何单位或者___对事故隐患或者安全生产违法行为,均有权向负有安全生产监督管理职责的部门报告或者举报。(单选题)
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低压电工作业是指对___V以下的电气设备进行安装、调试、运行操作等的作业。(单选题)
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在易燃易爆场所使用的照明灯具应采用___灯具。(单选题)
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电机在正常运行时的声音,是平稳、轻快、___和有节奏的。(单选题)
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对电机轴承润滑的检查,___电动机转轴,看是否转动灵活,听有无异声。(单选题)
A. 通电转动
B. 用手转动
C. 用其它设备带动
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一般线路中的熔断器有___保护。(单选题)
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利用交流接触器作欠压保护的原理是当电压不足时,线圈产生的___不足,触头分断。(单选题)
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螺旋式熔断器的电源进线应接在___。(单选题)
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【单选题】
In the eyes of the author, a successful engineering student is expected ______________.___
A. to be imaginative with a value system to guide him
B. to be a technical genius with a wide vision
C. to have an excellent academic record
D. to be wise and mature
【单选题】
The author's experience shows that he was ________.___
A. creative
B. ambitious
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D. unrealistic
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The underlined word "they" in "... together they threaten to confuse." (Para.5) refers to ____________.___
A. practicality and rationality
B. engineering and the liberal arts
C. reality and noble ideals
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It can be learned from the passage that the Ouchidas' house __________.___
A. failed to meet energy conservation standards
B. was designed and constructed in a scientific way
C. is well worth the money spent on its construction
D. is almost faultless from the point of energy conservation
【单选题】
What made the Ouchidas' new house a horrible dream?___
A. Lack of fresh air.
B. Gas leakage in the kitchen.
C. The newly painted walls.
D. Poor quality of building materials.
【单选题】
The underlined word "accentuate" (Para. 3) most probably means "________".___
A. worsen
B. accelerate
C. relieve
D. improve
【单选题】
Why were cracks in old houses not a big concern?___
A. Because environmental protection was given top priority.
B. Because indoor cleanness was not emphasized.
C. Because they were technically unavoidable.
D. Because energy used to be inexpensive.
【单选题】
This passage is most probably taken from an article entitled "_________".___
A. Energy Conservation
B. Air Pollution Indoors
C. House Building Crisis
D. Traps in Building Construction
【单选题】
We need to plan ahead in order to ___________.___
A. keep a record of all the events
B. better organize our activities
C. store everything in our head
D. pile up little tasks neatly
【单选题】
Strategic times are best for us to ___________.___
A. save energy
B. check e-mails
C. study efficiently
D. organize activities
【单选题】
Which of the following could be used as a motivation to do our assignments?___
A. Remembering our urgent tasks.
B. Any activities we're eager to do.
C. Taking a break in the afternoon.
D. The promise to study efficiently.
【单选题】
What can help us to keep refreshed throughout the day?___
A. Doing some physical exercise.
B. Taking a short nap in the afternoon.
C. Rushing through some assignments.
D. Playing a game of chess with a friend.
【单选题】
Which of the following could be the best title for this article?___
A. Study Habits and Time Management
B. Business Management and Leadership
C. University Education and Campus Life
D. Life Goals and Academic Development
【单选题】
It is implied in the text that it is hard to ________.___
A. carry life learning though
B. tell the nature of life learning
C. learn without going to school
D. find a specially trained teacher
【单选题】
According to the author, the schooling framework often ________.___
A. produces slow students with poor memories
B. ignores some parts of the official curriculum
C. fails to provide enough knowledge about life
D. gives little care to the quality of teaching materials
【单选题】
Life learners recognize that learning will not be difficult if they are _________.___
A. clear about why to learn
B. careful to make a time table
C. able to respect other people
D. cautious about any mistakes
【单选题】
According to the author, life learning ________.___
A. could prevent one from running risks
B. could be a road full of trials and errors
C. makes a kid independent of his parents
D. teaches a kid how to avoid being scorned
【单选题】
Through life learning, children ________.___
A. will grow without the assistance from parents
B. will learn to communicate with the real world
C. will be driven to learn necessary life knowledge
D. will be isolated from the negative side of society
【单选题】
A good title for this passage is __________.___
A. Sleep
B. Good Health
C. Dreams
D. Work and Rest
【单选题】
The word drowsy in the last paragraph means __________.___
A. sick
B. stand up
C. asleep
D. a little sleepy
【单选题】
This passage suggests that not getting enough sleep might make you ___________.___
A. dream more often
B. have poor health
C. nervous
D. breathe quickly
【单选题】
During REM, ___________ .___
A. your eyes move quickly
B. you dream
C. you are restless
D. both A and B
【单选题】
The average number of hours of sleep that an adult needs is __________.___
A. approximately six hours
B. around ten hours
C. about eight hours
D. not stated here
【填空题】
4、Sjogren syndrome___
【填空题】
2、唇腭裂治疗的新概念是___,即___。常包括以下医师:___及___、___、___。
【填空题】
3、颌面部外伤后易出现两类窒息:阻塞性窒息和___、阻塞性窒息常见于三种情况:___、___、___。