相关试题
【判断题】
如果电容器运行时,检查发现温度过高,应加强通风。
【判断题】
静电现象是很普遍的电现象,其危害不小,固体静电可达200kV以上,人体静电也可达10KV以上。
【判断题】
RCD的额定动作电流是指能使RCD动作的最大电流。
【判断题】
绝缘棒在闭合或拉开高压隔离开关和跌落式熔断器,装拆携带式接地线,以及进行辅助测量和试验使用。
【判断题】
验电是保证电气作业安全的技术措施之一。
【判断题】
在安全色标中用绿色表示安全、通过、允许、工作。
【判断题】
相同条件下,交流电比直流电对人体危害较大。
【判断题】
按照通过人体电流的大小,人体反应状态的不同,可将电流划分为感知电流、摆脱电流和室颤电流。
【判断题】
通电时间增加,人体电阻因出汗而增加,导致通过人体的电流减小。
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根据用电性质,电力线路可分为动力线路和配电线路。
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过载是指线路中的电流大于线路的计算电流或允许载流量。
【判断题】
在选择导线时必须考虑线路投资,但导线截面积不能太小。
【判断题】
异步电动机的转差率是旋转磁场的转速与电动机转速之差与旋转磁场的转速之比。
【判断题】
对绕线型异步电机应经常检查电刷与集电环的接触及电刷的磨损,压力,火花等情况。
【判断题】
对电机轴承润滑的检查,可通电转动电动机转轴,看是否转动灵活,听有无异声。
【判断题】
同一电器元件的各部件分散地画在原理图中，必须按顺序标注文字符号。
【判断题】
能耗制动这种方法是将转子的动能转化为电能,并消耗在转子回路的电阻上。
【判断题】
锡焊晶体管等弱电元件应用100W的电烙铁。
【判断题】
剥线钳是用来剥削小导线头部表面绝缘层的专用工具。
【判断题】
移动电气设备可以参考手持电动工具的有关要求进行使用。
【判断题】
当灯具达不到最小高度时,应采用24V以下电压。
【判断题】
低压验电器可以验出500V以下的电压。
【判断题】
危险场所室内的吊灯与地面距离不少于3m。
【判断题】
用电笔验电时,应赤脚站立,保证与大地有良好的接触。
【判断题】
为了安全可靠,所有开关均应同时控制相线和零线。
【判断题】
在带电灭火时,如果用喷雾水枪应将水枪喷嘴接地,并穿上绝缘靴和戴上绝缘手套,才可进行灭火操作。
【判断题】
电工特种作业人员应当具备高中或相当于高中以上文化程度。
【判断题】
取得高级电工证的人员就可以从事电工作业。
【判断题】
当导体温度不变时,通过导体的电流与导体两端的电压成正比,与其电阻成反比。
【判断题】
摇测大容量设备吸收比是测量(60秒)时的绝缘电阻与(15秒)时的绝缘电阻之比。
【判断题】
用万用表R×1KΩ欧姆档测量二极管时,红表笔接一只脚,黑表笔接另一只脚测得的电阻值约为几百欧姆,反向测量时电阻值很大,则该二极管是好的。
【判断题】
接地电阻测试仪就是测量线路的绝缘电阻的仪器。
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【填空题】
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6 During the weeks of discussion,delegations
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4 A number of countries are [ ]their efforts to send out food to the area worst affected by the flood.
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On hering the latest news about your mother's ill health, I [ ]canceling your reservation at the Sheraton.
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There was an obvious indication that the police who have to enforce the new law were not[ ] the general discontent.
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When she heard of her failure in the experiment, her eyes[ ]tears; whether it was of shame, frustration, orgrief was difficult to tell.
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Rose knows that continuous letters fromJohn, together with countless roses are aimedat making her[ ]him.
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[ ]public school for drinking and smoking and then failing inshow business as a singer, she joined her father's business 10 years ago.
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Since the great scandals in banking,many people in the Country have[ ]the prospects of economic recovery within a few years.
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The parents were quite happy to[ ]our suggestion because had taked their most important concernsinto consideration.
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1When employees participated in the problem-solving process, they were muchvmore willing to [ ] solutions to the problems.___
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2 A strong police force has been placed between the two [ ]group in the village to prevent fighting and killing.___
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3 Although personally we believe this to be of only secondary importance, its potential role in [ ] innovative acts cannotbe.___
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5 Western nations have older and shrinking populations since they entered the 21stcentury and their [ ] birth rates have also posed problems___
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6 She didn't want to marry him and was [ ] against him because he had only a bachelor's degree and didn't meet her expectations for marriage.___
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7 The president is in trouble and will have to work hard to [ ] his credibility after people discovered that he was not telling the truth.___
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8 To study a number of subjects in the humanities has been both enjoyable and [ ]providing me with a new and different perpective on the world in which we live.___
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1Though he was 80 years old, blind and hardly able to walk, his family [ ]him so much that they could hardly bear the thought of his death.___
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3 Please don't forget the Tourist Guide , which should [ ] when you travel to different places in Asia And Europe for the next few weeks.___
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4 These people living in this area are still [ ] their traditions which give their life meaning and help them in answering many questions.___
