问题 问答题 简答题

什么是电气设备的额定值?有何意义?

答案

参考答案:

对任何一个电器设备,为了安全可靠地工作,都必须有一定的电流、电压和功率的极限值和规定值,这种规定值就称为额定值。如一个标明额定值为220V、40W的白炽灯泡,就表示该灯泡应在220V电压下使用,灯泡消耗的功率为40W,此时灯泡发光正常,使用寿命能够得到保证,若超过规定值使用,则灯丝会因温度过高,使用寿命大大缩短,严重时甚至立即烧断。而低于规定值使用,则灯光发暗,经济性达不到要求。同样电网中的其他电气设备,如电压器、电容器、互感器等也存在同样的问题,因此额定值的提出,有着具体的实际意义。

单项选择题
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阅读理解

     When we think of leadership,  we often think of strength and power.But what are these really,  and how do they operate?

     Leadership today is not about forcing others to do things.Even if this is possible,  it is shortterm,  and

tends to produce unexpected and unwanted results.If you order someone to do something against their

will,  they may do it because they feel they have to,  but the anger they feel will do more harm in the long

term.They will also experience fear.

     Fear causes the thinking brain to shut down,  making the person unable to function at his or her best.If

they connect you with this emotion of fear,  they will become less functional around you,  and you will have succeeded in not only shooting yourself in the foot,  but possibly making a very good employee or partner unable to perform effectively.Fear does no good to leadership.

     The way we influence people in a lasting way is by our own character,  and our understanding and use of emotion.We can order someone to do something,  which may be part of the work day; or we can

employ them at the emotional level,  so they will become fully devoted to the projects and provide some of their own motivation.Today's work place is all about relationships.

     Anyone works harder in a positive environment in which they're recognized and valued as a human

being as well as a worker.Everyone produces just a bit more for someone they like.Leaders understand

the way things work.They know the pay check is not the single most important factor in the work life of

most people.

     The true strength of leadership is an inner strength that comes from the confidence of emotional

intelligence-knowing your own emotions,  and how to handle them,  and those of others.Developing your

emotional intelligence is the single best thing you can do if you want to develop your relationship with

people around you,  which is the key to the leadership skills.

1. The writer thinks that it is not________for us to connect leadership with strength and power.

A. possible  

B. necessary

C. easy  

D. effective

2. People may NOT be working hard when________.

A. they're regarded as human beings

B. they like their leaders

C. money is taken as the most important

D. leaders understand the way things work

3. From the passage,  we can conclude that________is the key to making a good leader.

A. developing one's emotional intelligence

B. in fluencing others in one's own way

C. producing some unexpected results

D. having confidence in one's ability

4. This passage is most helpful to those who________.

A. have strength and power

B. are going to make a speech

C. would like to be leaders

D. are to be excellent employees