【单选题】
高电阻液体在管道中流动且流速>___时，就能产生静电。
A. 0.2m/s
B. 0.5m/s
C. 1m/s
D. 2m/s
查看试卷，进入试卷练习
微信扫一扫，开始刷题
相关试题
【单选题】
低压配电网电气设备的保护接地电阻不超过___Ω。
A. 4
B. 10
C. 30
D. 大于30Ω
【单选题】
三相四线制系统不采用三芯电缆另加一根单芯电缆或以导线、电缆金属护套作___。
A. 中性线
B. 保护中性线
C. 保护线
D. 都不可以
【单选题】
携带型接地线应使用___。
A. 多股铜绞线
B. 多股铝绞线
C. 带透明护套的多股软铜线
D. 塑料硬铜线
【单选题】
II类电动工具，其额定电压超过___V。
A. 50
B. 220
C. 380
D. 660
【单选题】
接闪线的保护角一般应在___范围为宜。
A. 0°～l0°
B. 10°～20°
C. 20°～30°
D. 大于30°
【单选题】
在正常工作状态时，本质安全型设备各元件的电流不得大于其额定值得___倍。
【单选题】
依靠回路阻抗分压，将漏电设备故障对地电压限制在安全范围以内是___的。
A. 可能
B. 不可能
C. 有条件许可
D. 提高回路阻抗
【单选题】
感应电动势的大小与磁通的变化速度和载流线圈___成正比。
【单选题】
吸收比是从开始测量起第（ ）的绝缘电阻（ ）与第（ ）的绝缘电阻___的比值。
A. 15s/60s、R15/R60
B. 30s/60s、R30/R60
C. 45s/60s、R45/R60
D. 60s/15s、R60/R15
【单选题】
凡经互感器接入的电度表，其读数要___互感器的变比才是实际读数值。
【单选题】
接地电阻测量仪用120r/min的速度转动摇把时，表内发出___V左右的交流电压。
A. 200
B. 110
C. 100
D. 50
【单选题】
单人施行人工呼吸和心脏按压时应交替进行，按压次数和吹气次数的比例为___。
A. 5:1
B. 15:2
C. 15:3
D. 20:2
【单选题】
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小于___m。
A. 0.4
B. 0.7
C. 1
D. 1.4
【单选题】
一个电气连接部分或一个配电装置全部停电，则不同地点的工作，发给___张工作票。
【单选题】
足够的绝缘电阻能把___限制在很小的范围内。
A. 额定电流
B. 泄漏电流
C. 剩余电流
D. 直流电流
【单选题】
胶壳开关安装时，手柄要___。
A. 向下
B. 向上
C. 水平安装
D. 无所谓
【单选题】
停电设备有关的变压器和电压互感器，必须从___断开。
A. 高压侧
B. 低压侧
C. 高、低压两侧
D. 只要从高压侧断开，低压侧无要求
【单选题】
10kV及以下架空电力线路基坑，每回填___mm应夯实一次。
A. 200
B. 300
C. 400
D. 500
【单选题】
在1区、2区内的绝缘导线和电缆截面不应小于熔断器熔体额定电流的___。
A. 1
B. 1.25
C. 1.5
D. 2.5
【单选题】
充砂型设备的外壳应有足够的机械强度，颗粒直径为0.25～1.6mm。填充时，颗粒材料含水量不得超过___。
A. 0.1%
B. 0.15%
C. 0.2%
D. 0.3%
【单选题】
单人施行人工呼吸和胸外按压时，按压次数和吹气次数的比例为___。
A. 15、1
B. 3、1
C. 15、2
D. 5、3
【单选题】
当允许系统接地电阻不超过10Ω且三处以上重复接地时，重复接地电阻不应超过___Ω。
A. 10
B. 30
C. 100
D. 大干100
【单选题】
功率因数从0.5提高0.6，发电机正常供电的用电器的个数即从500个提高到___个。
A. 600
B. 650
C. 700
D. 800
【单选题】
锅炉的爆炸，压缩气体爆炸，液化气体超压引起的爆炸属___。
A. 化学性爆炸
B. 物理性爆炸
C. 生物性爆炸
D. 核裂变爆炸
【单选题】
将绝缘体与大地之间保持___Ω的电阻，以消除绝缘体上的静电电荷。
A. 103～104
B. 104～105
C. 105～106
D. 106～109
【单选题】
电动机型号Y2-132S-4上S的含义___。
A. 机座类别
B. 中心高度
C. 磁极对数
D. 绝缘等级
【单选题】
金属容器、隧道、矿井内等工作地点狭窄的场所应采用___V的安全特低电压。
【单选题】
螺口灯头的安装，在灯泡装上后，灯泡的金属螺口不能外漏，且应接在___上。
A. 相线
B. 中性线
C. 保护线
D. 地线
【单选题】
室内一般的灯具距离地面的高度不应小于___m。
A. 2.4
B. 2.2
C. 2
D. 1.8
【单选题】
接地线，严禁用___的方法进行接地。
A. 缠绕
B. 压接
C. 专用线夹
D. 接地刀闸
【单选题】
一般没有受潮的绝缘，吸收比不应___1.3。
【单选题】
工作票应由___填写签发。
A. 电气负责人
B. 工作负责人
C. 工作票签发人
D. 工作监护人
【单选题】
___是断路器的感测元件，用来感测电路特定的信号。
A. 电磁元件
B. 灭弧元件
C. 脱扣器
D. 操作机构
【单选题】
离接地体越远，一般到___m处时，电流密度为零。
【单选题】
以下哪一项不是填用第一种工作票的工作范围___。
A. 高压设备上工作需全部停电或部分停电的
B. 高压室内的二次接线和照明等回路上的工作
C. 需要将高压设备停电或采取安全措施
D. 在控制盘和低压配电盘的工作
【单选题】
楼梯顶一般不应低于工作人员的___。
A. 颈部
B. 胸部
C. 腰部
D. 无具体要求
【单选题】
应急照明应选用能___的照明光源。
A. 显色性好
B. 色温高
C. 快速点亮
D. 反射比强
【单选题】
电阻串联电路总电压等于各电阻的分电压___。
【单选题】
在某些对启动性能及调速有特殊要求的设备中，较多采用___。
A. 鼠笼式异步电动机
B. 感应式异步电动机
C. 双鼠笼式异步电动机
D. 绕线转子异步电动机
推荐试题
【单选题】
历史上最广泛、最彻底、最深刻的，不同于以往一切革命的最新类型的革命是 ___
A. 封建革命
B. 无产阶级革命
C. 资产阶级革命
D. 农民起义
【填空题】
explore ，transmit， resource， emerge，yield， pose， assume， confidence，inherit， comprehensive
Given the chance to show his ability, he regained [ ]and began to succeed in school
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
The new government has committed to [ ] emissions of greenhouse gases
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
My parents do not object to my taking part-time jobs, but they remind me not to let them [ ] my school work
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Anger, worry, disappointment, these negative emotions [ ] your heart, brain and body
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
If a person adopts an unhealthy lifestyle, he will surely be [ ]developing diseases.
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Most people were ready to give up on him when he [ ] of school, but later he returned and earned his degree
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Drinking too much can increase the risk of developing high blood pressure, which [ ] can lead to heart attack or stroke
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Low-cost airlines are emerging all over Asia; this will [ ]the development of the worlds air-travel market as a whole
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
When you move to a new country, you may find the food there strange and you may miss the familiar smells of the food [ ] in your country
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
Although he kept trying and failing, I always [ ] the belief that he would succeed one day.
【填空题】
take a toll on，in other words ，drop out，in turn ，at risk (of) ，interfere with，be accustomed to， contribute to，cut back on ，hold on to
The tax only affects people with an annual income over $200,000-[ ], it will only attect the very rich.
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Studies[ ]that children who often take part in cooperative programs benefit a lot more than other children
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
They are such a(n) [ ] family- they must have been shocked when their son dyed(染) his hair pink,
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Testing students by examinations has long been regarded as a reliable way to [ ]students'ability
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Many power stations have been modernized to give off less pollution, or they were moved further away from the living areas in order to [ ] the damage,
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Unemployment has come down slightly, but this does not [ ]the fact that it is still a major problem
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Mr. Smith is not doing well; the doctor told us that several colds [ ]his health
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
The best way to deal with problems at home is to talk things out calmly and honestly and try to reach a(n) [ ]
【填空题】
open the door to，In advance，all at once，reap the benefits (of)， make the most of，over time， get by， stand a chance (of)，remind of， take pleasure in，
Experts say our company is amazing in that sales have been increasing steadily [ ]
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
After 10 years of full-time training, she has,finally [ ] as a professional dancer.
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
[ ], what is the point in taking part in the competitive event if the result is only to prove how incompetent you are?,
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Redecorating the house is a challenging task. It's necessary to [ ] the wallpaper first.
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
I never really had any problems with change. On the contrary, I welcome change [ ]
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
A lot of what we [ ] is made from raw materials which are not renewable
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Megan and John realized that their house was too messy for a new baby, so they decided to [ ] their house before the baby was born
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
Jennifer couldn't [ ] her tears when she saw the sick children at a new blood cancer center in Virginia
【填空题】
make it， with open arms ，strip off，keep back，
free of/ from ，after all，straighten up， throw away
We want to give all children a world [ ] violence
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
Fortunately, the accident didn't [ ] many people, for there was little traffic at that hour.
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
She[ ] her ambition of becoming a fashion designer after years of hard work
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
They kept on trying their best to develop
their business, but in such [ ]market competition, they had no Idea if success would come along one day
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
As music plays an important role in our life, many music teachers and educators [ ] taking up a musical instrument at a young age
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
This rule should be entirely clear in the minds of everyone and should not be misunderstood under any [ ]
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
My daughter was shy; she was afraid to ask questions,[ ] to questions in class,or talk with other children
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
I got from him only a letter, which was put on my office desk; [ ] to the receipt of this letter I have never heard from him
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
The duties to provide services for children in need are not [ ] to the local social services department
【填空题】
advocate，involve，confine，respond，subsequent ，distinct ，intense， fulfill，circumstance， reconcile
We pray that all nations be [ ] and that all people around the world live in peace
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
It was reported the president had [ ]to fight If war was necessary,even if it meant destroying his chances of re-election
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
I had to [ ] one of my email accounts as it was filled with junk mail
【填空题】
controversial，assess， resolve，decrease，alter，abandon，indicate，undermine，compromise， conventional
Darwin's theory of evolution remains[ ] partly because it challenges the religious belief that God created man
