【判断题】
验电是保证电气作业安全的技术措施之一。
A. 对
B. 错
查看试卷,进入试卷练习
微信扫一扫,开始刷题
答案
A
解析
暂无解析
相关试题
【判断题】
摇表在使用前,无须先检查摇表是否完好,可直接对被测设备进行绝缘测量。
A. 对
B. 错
【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。
A. 对
B. 错
【判断题】
一般情况下,接地电网的单相触电比不接地的电网的危险性小。
A. 对
B. 错
【判断题】
一号电工刀比二号电工刀的刀柄长度长。
A. 对
B. 错
【判断题】
移动电气设备电源应采用高强度铜芯橡皮护套硬绝缘电缆。
A. 对
B. 错
【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。
A. 对
B. 错
【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。
A. 对
B. 错
【判断题】
因闻到焦臭味而停止运行的电动机,必须找出原因后才能再通电使用。
A. 对
B. 错
【判断题】
用避雷针、避雷带是防止雷电破坏电力设备的主要措施。
A. 对
B. 错
【判断题】
用电笔检查时,电笔发光就说明线路一定有电。
A. 对
B. 错
【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。
A. 对
B. 错
【判断题】
用钳表测量电动机空转电流时,不需要档位变换可直接进行测量。
A. 对
B. 错
【判断题】
用钳表测量电动机空转电流时,可直接用小电流档一次测量出来。
A. 对
B. 错
【判断题】
用钳表测量电流时,尽量将导线置于钳口铁芯中间,以减少测量误差。
A. 对
B. 错
【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。
A. 对
B. 错
【判断题】
用星-三角降压启动时,启动转矩为直接采用三角形联结时启动转矩的1/3。
A. 对
B. 错
【判断题】
有美尼尔氏征的人不得从事电工作业。
A. 对
B. 错
【判断题】
右手定则是判定直导体做切割磁力线运动时所产生的感生电流方向。
A. 对
B. 错
【判断题】
幼儿园及小学等儿童活动场所插座安装高度不宜小于1.8m。
A. 对
B. 错
【判断题】
雨天气,即使在室内也不要修理家中的电气线路、开关、插座等。如果一定要修要把家中电源总开关拉开。
A. 对
B. 错
【判断题】
载流导体在磁场中一定受到磁场力的作用。
A. 对
B. 错
【判断题】
再生发电制动只用于电动机转速高于同步转速的场合。
A. 对
B. 错
【判断题】
在安全色标中用红色表示禁止、停止或消防。(
A. 对
B. 错
【判断题】
在安全色标中用绿色表示安全、通过、允许、工作。
A. 对
B. 错
【判断题】
在爆炸危险场所,应采用三相四线制,单相三线制方式供电。
A. 对
B. 错
【判断题】
在采用多级熔断器保护中,后级熔体的额定电流比前级大,以电源端为最前端。
A. 对
B. 错
【判断题】
在串联电路中,电流处处相等。
A. 对
B. 错
【判断题】
在串联电路中,电路总电压等于各电阻的分电压之和。
A. 对
B. 错
【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。
A. 对
B. 错
【判断题】
在带电维修线路时,应站在绝缘垫上。
A. 对
B. 错
【判断题】
在电气线路安装时,导线与导线或导线与电气螺栓之间的连接最易引发火灾的连接工艺是()。
A. 对
B. 错
【判断题】
在电气原理图中,当触点图形垂直放置时,以“左开右闭”原则绘制。
A. 对
B. 错
【判断题】
在电压低于额定值的一定比例后能自动断电的称为欠压保护。
A. 对
B. 错
【判断题】
在断电之后,电动机停转,当电网再次来电,电动机能自行起动的运行方式称为失压保护。
A. 对
B. 错
【判断题】
在高压操作中,无遮拦作业人体或其所携带工具与带电体之间的距离应不少于0.7m。
A. 对
B. 错
【判断题】
在高压线路发生火灾时,应采用有相应绝缘等级的绝缘工具,迅速拉开隔离开关切断电源,选择二氧化碳或者干粉灭火器进行灭火。
A. 对
B. 错
【判断题】
在供配电系统和设备自动系统中,刀开关通常用于电源隔离。
A. 对
B. 错
【判断题】
在没有用验电器验电前,线路应视为有电。
A. 对
B. 错
【判断题】
在三相交流电路中,负载为星形接法时,其相电压等于三相电源的线电压。
A. 对
B. 错
【判断题】
在设备运行中,发生起火的原因是电流热量是间接原因,而火花或电弧则是直接原因。
A. 对
B. 错
推荐试题
【单选题】
Tom is a book lover. ______ likes reading very much. A. He B. She C. You D. It
A. A
B. B
C. C
D. D
【单选题】
—May I listen to the music here, Mr. White? —Sorry, you’d better it like that. A. not to do B. not do to C. dont do D. not do
A. A
B. B
C. C
D. D
【单选题】
3.—Did you have a good time at Lauras birthday party? — Yes, indeed. Its several years ________ I enjoyed myself so much. A. when B. before C. since D. that
A. A
B. B
C. C
D. D
【单选题】
4. —___________ is the Summer Palace from here? About three kilometers away. You can take the No. 35 bus. A. How long B. How far C. How often D. How much
A. A
B. B
C. C
D. D
【单选题】
5. I was looking for a birthday gift for my mother, but I couldnt find ______ suitable. A. anything B. something C. nothing D. everything
A. A
B. B
C. C
D. D
【单选题】
6. A friend of my ____ and I are going to visit_______ next week. A. father; Browns B. father's; Browns C. father; the Browns D. father's; the Browns
A. A
B. B
C. C
D. D
【单选题】
7. She ______ very hard since she came to our school. A. studies B. has studied C. is studying D. studied
A. A
B. B
C. C
D. D
【单选题】
8. — Who will send you to the new school, your mom or your dad? — _______. Ill go there by myself. A. Both B. Either C. Neither D. None
A. A
B. B
C. C
D. D
【单选题】
9.—Well do what we can ____English well this term. —It’s high time for you to work hard. A. study  B.to study  C. be studied   D. be studying
A. A
B. B
C. C
D. D
【单选题】
10. —I’m going to Flower Bookstore. Could you tell me ______? — Sorry, I don’t know. I’m new here. A. where it is B. where was it C. where is it D. where it was
A. A
B. B
C. C
D. D
【单选题】
11. How do you like the dishes, Eric? — Fantastic! Nothing tastes ________. A. nice B. better C. terrible D. worse
A. A
B. B
C. C
D. D
【单选题】
12. ______ Lin Feng has to work late, she always wears a smile on her face. A. Because B. If C. Until D. Though
A. A
B. B
C. C
D. D
【单选题】
13.You can save money _______ you buy cheaper things. A. before B. unless C. if D. until
A. A
B. B
C. C
D. D
【单选题】
14. We will have a _________ holiday after the exam. A. two-month B. two month’s C. two month D. two-months
A. A
B. B
C. C
D. D
【单选题】
15. —We will build an underground in Xuzhou before 2015. — Wow, _______! Will it pass our place? A. what an excited news B. how excited the news is C. what exciting news D. how exciting
A. A
B. B
C. C
D. D
【单选题】
16. — Emily, here’s a dictionary.I hope it will help you in some way. — Thank you.It’s ________ what I need. A. almost B. still C. only D. just
A. A
B. B
C. C
D. D
【单选题】
17. —Oh.I’m hungry.Mum, can I have the hamburger on the plate? —No.It tastes . A. terribly B. terrible C. good D. well
A. A
B. B
C. C
D. D
【单选题】
18. —We can invite our teachers to the farewell party next Saturday. —Yes, ______? I’ll call them at once. A. what for B. what C. why not D. why
A. A
B. B
C. C
D. D
【单选题】
19.You can ________ ask the old man to move away to any other place because he has lived ________ here for at least sixty years. A. hardly; alone B. hard; alone C. hardly; lonely D. hardly; lonely
A. A
B. B
C. C
D. D
【单选题】
20.—I’m going back to see my grandparents this weekend. —________. A. It’s very nice of you B. You’d better hurry C. Say goodbye to them D. Give my best wishes to them
A. A
B. B
C. C
D. D
【单选题】
21.—Why not take ____ umbrella with the sign “Made in China”? It is useful. —What _______ good advice it is!    A. an; a B. a; a C. an; \ D. \; a
A. A
B. B
C. C
D. D
【单选题】
22. —Do you know the boy________ is sitting next to Peter? — Yes. He is Peter’s friend. They are celebrating his ________ birthday. A. who; ninth B. that; ninth C. /; ninth D. which; ninth
A. A
B. B
C. C
D. D
【单选题】
23. It was dark, ______ I couldnt see what was happening. A. or B. though C. but D. so
A. A
B. B
C. C
D. D
【单选题】
24.—You can use MSN to talk with Vivien on the Internet. —I know. But can you tell me ________? A. what I can use it B. when I can use it C. why can I use it D. how can I use it
A. A
B. B
C. C
D. D
【单选题】
25. _______ are you going to the School Uniform Exhibition, Amy ? To learn about different styles of school uniform. A. What B. Where C. Which D. Why
A. A
B. B
C. C
D. D
【单选题】
( ) 26. Where does the writer of "The little Prince" come from? A.England. B.France. C.America. D.China.
A. A
B. B
C. C
D. D
【单选题】
( ) 27. What does the prince do after the fox tells him a secret? A.He cares more about a flower and a sheep. B.He meets many more strange adults on other planets. C.He realizes his love for the rose and he goes back to his planet.   D.He discovers interesting things such as a snake, other roses and a fox
A. A
B. B
C. C
D. D
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________. A.the adult world B.the planet B -612 C.a rose and a fox D.the adventure of a young prince
A. A
B. B
C. C
D. D
【单选题】
( ) 29. What is the writer's main purpose(目的)in writing this passage?    A.To tell the readers his life story.    B.To tell people what kind of person his father was.    C.To tell the readers what present he got from his father.    D. To let people know how poor he was.
A. A
B. B
C. C
D. D
【单选题】
( ) 30. Why did the father not ask his son not to do this and do that?    A.Because he felt quite confident of his son.    B.Because he was born from a poor family.    C.Because he was a man of few words.    D.Because he didn't want to be much too strict with his son.
A. A
B. B
C. C
D. D
【单选题】
( ) 31. What would someone learn from this passage?    A.How to live by oneself. B.How to stand on one's own feet.    C.What a good father should do. D.What the self-important is like.
A. A
B. B
C. C
D. D
【单选题】
( ) 32. What may be the proper Chinese for the underlined part in the passage?    A.闲暇时光 B.学费 C.精神空虚 D.经济不足
A. A
B. B
C. C
D. D
【单选题】
( ) 33. Why did Natalie Smith pay for the six cars behind her? A. She had seven tickets. B. She hoped to please others. C. She knew the car drivers well. D. She wanted to show kindness.
A. A
B. B
C. C
D. D
【单选题】
( ) 34. Judy Foreman copied down the phrase because she ___ . A. thought it was beautifully written B. wanted to know what it really meant C. decided to write it on a warehouse wall D. wanted her husband to put it up in the classroom
A. A
B. B
C. C
D. D
【单选题】
( ) 35. Who came up with the phrase according to the passage? A. Judy Foreman. B. Natalie Smith. C. Anne Herbert D. Alice Johnson.
A. A
B. B
C. C
D. S
【单选题】
( ) 36. What can we infer from the last paragraph? A. People should practice random kindness to those in need. B. People who receive kindness are likely to offer it to others. C. People should practice random kindness to strangers they meet. D. People who receive kindness are likely to pay it back to the giver.
A. A
B. B
C. C
D. D
【单选题】
( ) 37.The greatest river for navigation is ___________. A. the Nile B. the Amazon C. the Mekong D. the Mississippi
A. A
B. B
C. C
D. D
【单选题】
( ) 38. From a dam, people can use the water for ___________. A. keeping the rivers clean B. only making electricity C. irrigation and making electricity D. washing clothes
A. A
B. B
C. C
D. D
【单选题】
( ) 39. The water in the river is polluted because of _____________. A. people's drinking water too much B. people's swimming in the river too much C. chemicals and other materials D. people's building a dam across a river
A. A
B. B
C. C
D. D
【单选题】
( ) 40. The best title of the passage is ___________. A. Rivers in Cities B. The importance of Rivers C. Transportation D. Natural Resources
A. A
B. B
C. C
D. D