相关试题
【判断题】
当电气火灾发生时首先应迅速切断电源,在无法切断电源的情况下,应迅速选择干粉、二氧化碳等不导电的灭火器材进行灭火。
【判断题】
tt系统是配电网中性点直接接地,用电设备外壳也采用接地措施的系统。
【判断题】
单相220v电源供电的电气设备,应选用三极式漏电保护装置。
【判断题】
带电机的设备,在电机通电前要检查电机的辅助设备和安装底座,接地等,正常后再通电使用。
【判断题】
使用改变磁极对数来调速的电机一般都是绕线型转子电动机。
【判断题】
电气安装接线图中,同一电器元件的各部分必须画在一起。
【判断题】
对电机各绕组的绝缘检查,如测出绝缘电阻不合格,不允许通电运行。
【判断题】
正弦交流电的周期与角频率的关系互为倒数的。
【判断题】
在三相交流电路中,负载为三角形接法时,其相电压等于三相电源的线电压。
【判断题】
欧姆定律指出,在一个闭合电路中,当导体温度不变时,通过导体的电流与加在导体两端的电压成反比,与其电阻成正比。
【判断题】
为了避免静电火花造成爆炸事故,凡在加工运输,储存等各种易燃液体、气体时,设备都要分别隔离。
【判断题】
在我国,超高压送电线路基本上是架空敷设。
【判断题】
手持电动工具有两种分类方式,即按工作电压分类和按防潮程度分类。
【判断题】
事故照明不允许和其它照明共用同一线路。
【判断题】
危险场所室内的吊灯与地面距离不少于3m。
【判断题】
停电作业安全措施按保安作用依据安全措施分为预见性措施和防护措施。
【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】
企业、事业单位的职工无特种作业操作证从事特种作业,属违章作业。
【判断题】
检查电容器时,只要检查电压是否符合要求即可。
【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。
【判断题】
接地电阻表主要由手摇发电机、电流互感器、电位器以及检流计组成。
【判断题】
接地电阻测试仪就是测量线路的绝缘电阻的仪器。
【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。
【判断题】
断路器在选用时,要求断路器的额定通断能力要大于或等于被保护线路中可能出现的最大负载电流。
【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。
【判断题】
刀开关在作隔离开关选用时,要求刀开关的额定电流要大于或等于线路实际的故障电流。
【判断题】
为了防止电气火花,电弧等引燃爆炸物,应选用防爆电气级别和温度组别与环境相适应的防爆电气设备。
【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。
推荐试题
【单选题】
___ I'd like to place an order please.
A. Can I help you?
B. I can help you.
C. What are you doing?
D. Why are you doing?
【单选题】
- Do you know the girl over there?___
A. How can I know?
B. Yes, I remember it now.
C. It's Sam, my teacher's daughter.
D. She is a good girl.
【单选题】
- Shall we go out for dinner tonight?____
A. No, you can't.
B. Yes, please.
C. Thank you, I don't want to.
D. Sorry, I have a report to finish.
【单选题】
- I think the reference book（参考书）is very helpful.____
A. Good idea.
B. So do I.
C. With pleasure.
D. No problem.
【单选题】
- I wish you success in your career.____
A. You are welcome.
B. I think so.
C. Yes, please.
D. The same to you.
【单选题】
- Would you like to come over tonight?____
A. Yes, last night.
B. Yes, over there.
C. Sure, I'd love to.
D. Yeah, I liked it too.
【单选题】
- How do I transfer calls? ____
A. Do as you like.
B. It is a bit difficult.
C. Let me show you.
D. Not at all.
【单选题】
- Thanks for inviting me, John, but I've already made other plans. ____. Maybe another time.
A. I hope you enjoy it
B. That's good
C. Oh! I'm sorry to hear that
D. Great! I really had a good time
【单选题】
- Thanks for the lovely party and the delicious food. ____
A. No, thanks.
B. Never mind.
C. Thank you for coming.D.That's all right.
【单选题】
- Why didn't you tell me? ____
A. Sorry, I forgot.
B. I'm sorry you should wait.
C. I don't know.
D. I'd love to.
【单选题】
- What do you plan to do after the exam? ____ How about you?
A. I hate taking exams.
B. I like making plans.
C. Nothing special.
D. I've changed my mind.
【单选题】
- Tom told me that you collect stamps. ____
A. What do you mean?
B. I don't think so.
C. Why did he tell you?
D. Yes, I do. Do you?
【单选题】
- This is a challenging job. Who wants it？____
A. I'll take it.
B. It's a good idea.
C. You bet!
D. No sweat!
【单选题】
- I'm taking my driving test tomorrow. ___!
A. Cheers
B. Good luck
C. Come on
D. Congratulations
【单选题】
- ABC Company, may I help you? ____
A. I am Jack. May I speak to Miss Jenny?
B. This is Jack speaking. May I speak to Miss Jenny?
C. This is Jack speaking. Can I find Miss Jenny?
D. I am Jack. Can I find Miss Jenny?
【单选题】
- You have won the football game. Congratulations! ____
A. We are really lucky.
B. No one else could do it.
C. Oh, not really.
D. It's nice of you to say so.
【单选题】
- Excuse me, when will the 17:15 train arrive____
A. I don't tell you.
B. It's been delayed one hour.
C. You have to be patient.
D. Don't ask me.
【单选题】
- Is John there?____
A. Speaking.
B. I'm not Mary.
C. Who are you?
D. Mary is well today.
【单选题】
- Would you like to join us for Sunday dinner____
A. It's nice of you to invite me.
B. How about the food?
C. I like onion soup.
D. I'm sorry I missed the fun last time.
【单选题】
- Could you tell me where the nearest parking lot is?____
A. Don't ask me.
B. Parking is very difficult.
C. Sorry, I'm a stranger here.
D. Sorry, you can't park here.
【单选题】
- Sorry, ___
A. here you are.
B. take it.
C. it's taken.
D. never mind.
【单选题】
－What's this in English? ____
A. It's a map.
B. That is a map.
C. Yes, it's a map.
D. No, it isn't.
【单选题】
- I hear you got through your exam. Congratulations!____
A. No. I didn't do well enough.
B. Who told you that?
C. Thanks.
D. Yes, I got a good mark.
【单选题】
- Don't forget to come to my party this evening!___
A. I can't.
B. I won't.
C. I don't.
D. I will.
【单选题】
- Jim, please don't put your head out of the window on the bus. It's dangerous!___
A. Good idea.
B. Sorry, I won't do it again.
C. It doesn't matter.
D. It's good.
【单选题】
-How about going fishing?___, I have no patience for that.
A. Excuse me
B. Sorry
C. Pardon
D. Apologize
【单选题】
- Thanks for the lovely and delicious food______.
A. No thanks
B. Never mind
C. All right
D. My pleasure
【单选题】
－ Haven't seen you for ages. Let's have a get-together next week._____
A. Great idea.
B. Welcome!
C. Yes, of course.
D. No, thanks.
【单选题】
- Do you mind if I switch off the radio? ______. Go ahead.
A. Never mind
B. No way
C. No, not at all
D. No, you'd better not
【单选题】
- Could I use your bike for a moment? ___
A. It's well.
B. It doesn't matter.
C. By all means.
D. I have no idea.
【单选题】
-How do you like the story?_______.
A. I'd like to read it
B. I like it very much
C. fine, thank you
D. It's very interesting
【单选题】
- I'll sorry to trouble you.______.
A. Don't say so
B. OK
C. It doesn't matter
D. That's fight
【单选题】
- We ordered 20 boxes of your products, but we have only got 19. - ____
A. You do not have to.
B. It does not matter.
C. We will send another tomorrow.
D. Nothing serious.
【单选题】
--Will you please give the note to him? _________.
A. Certainly, I'll give it to him
B. No, please not
C. Sorry, I don't
D. Yes, please do
【单选题】
- Thank you ever so much for your lovely gift____
A. Never mind
B. I'm glad you like it.
C. Please don't say so.
D. No, It's not so good.
【单选题】
- I'd like to invite you to dinner this Saturday, Mr. Smith.____
A. Oh, no. let's not.
B. I'd rather stay at home.
C. I'm sorry, but I have other plans.
D. Oh, no. That'll be too much trouble.
【单选题】
- Could you please open the window?____
A. I can't.
B. Go ahead.
C. Sure.
D. It's really very kind.
【单选题】
- Do you think I can borrow your bike for a few hours?____
A. I'm afraid you can.
B. I'm sorry, but I really need it this afternoon.
C. Yes, I don't think so.
D. I'll think about it later.
【单选题】
- Thank you very much for the dictionary you sent me.____
A. No thanks.
B. I'm glad you like it.
C. Please don't say so.
D. No, it's not so good.
【单选题】
- How do you like the movie we saw yesterday?____
A. You are welcome.
B. How about you?
C. I've never seen a better movie than it.
D. It is very expensive.
