问题 问答题 简答题

解释剥线、压接时电缆不能断股的原因?

答案

参考答案:不能断股的原因:

1、为了保证导线的电气性能和机械性能;

2、如果断股,导体的横截面积会减小,当有电流通过时,由于截面积变小,内阻增大,故会引起导线连接处热量增加,久而久之就会引起老化,严重会引起烧损现象。

单项选择题
阅读理解

If you look up the word “create” in the dictionary , you will find it means “to bring into being, to cause to exist something each of us does daily”.

We are creative whenever we look at or think about something in a new way First, this includes an awareness of our surroundings.It means using all of our senses to become aware of our world.This may be as simple as being aware of color and texture(质地),as well as taste, when we plan a meal.Above all, it is the ability to notice things that others might miss.

A second part of creativity is an ability to see relationships among things.If we believe the expression,“There is nothing new under the sun, the creativity is remaking or recombining(重组) the old in new ways.”For example, we might do this by finding a more effective way to study or a better way to arrange our furniture, or we might make a new combination of camera lenses and filters to create an unusual photograph.

A third part of creativity is the courage and drive to make use of our new ideas, to ask for them to achieve some new results.To think up a new idea is one thing; to put the idea to work is another.

These three parts of creativity are included in all the great works of geniuses, but they are also included in many of our day-to-day activities.

小题1:Which of the following activities is NOT a creative one according to the passage?

A.To prepare for a meal.

B.To arrange the furniture in a special way.

C.To buy some books from a bookstore.

D.To“write”a letter with the computer.小题2:“There is nothing new under the sun” really implies that _________.

A.a new thing can only be created at the basis of earlier things

B.a new thing is only a tale

C.we can seldom create new things

D.we can hardly see really new things in the world小题3:What does the author think about the relationship between a new thought and its being put into

practice?

A.It’s more difficut to create a new thought than to use it in practice.

B.To find a new thought will clearly lead to the production of a new thing.

C.A man with an excellent ability of practice can easily become an inventor.

D.One may come up with a new thought, but can not put it into practice.小题4:The best title for this passage is__________.

A.How to Develop One’s Creativity

B.What Is Creativity

C.The Importance of Creativity

D.Creativity, a Not Faraway Thing