人类最早发现磁现象是从磁铁开始的,后来才逐渐认识到磁与电的联系.磁铁有N极和S极

题型:填空题

问题:

人类最早发现磁现象是从磁铁开始的,后来才逐渐认识到磁与电的联系.磁铁有N极和S极,它们同极相斥异极相吸,这一点与正负电荷有很大的相似性.所以人们可以假定在一根磁铁的两极上有一种叫“磁荷”的东西,N极上的叫“正磁荷”,S极上的叫“负磁荷”,同号磁荷相斥,异号磁荷相吸,磁荷间的作用是通过磁场实现的.磁荷周围存在着磁场,磁场对场中的磁荷有力的作用.实验证明同一磁荷在磁场中不同的位置受到的磁场力是不同的,而磁场中同一位置对不同的磁荷作用力也不同,但作用力的大小(用F表示)与磁荷所带的磁荷量(用qm表示)成正比.为了描述磁场的性质,可根据磁场对磁荷有作用力这一特性定义一个物理量,我们称其为“磁场强度”(用H表示,注意:不是磁感应强度B).请你用比值定义法给磁场强度下一个定义,并写出定义公式.

定义:

公式:

考点:磁感应强度
题型:填空题

写出反义词。

1. easy-                     2. top-                     3. quiet-                        4. left-                       5. small-                

6. quick-                   7. new-                    8. long-                        9. white-                    10. this-               

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第二节(共5小题,每小题2分,满分10分)

根据短文内容,从下框的A~F选项中选出能概括每一段主题的最佳选项。选项中有一项为多余项。

AGift giving proven to be valuable.

B.Memories from gift giving

C.Moments and events for gift giving

D.Various functions of gift giving

E.Gift giving as a wasteful practice

F.Gift giving as a two-way social activity

G.Gift Giving

61. _____________

There are many occasions(场合) for giving gifts in modern industrialinzed societies;birthdays,naming ceremonies, weddings, anniversaries, New Year, It is common to give gifts on many of these celebrations in western cultures. In addition, special events, such as one’ s first day of school or graduation from university, often require gift fiving.

62._____________

What is happening when we give gifts? Most important, we are exchanging gifts. If someone gives me a gift for my birthday, I know that I am usually expected to give one on his or her next birthday. A gift builds up or confirms a social oblingation(义务).

63.__________

Gifts tighten personal relationships and provide a means of communication between loved ones. People say that a gift lets the recipient(接受者) know we are thinking of them, and that we want to make the person “feel special.”We want people to feel wanted, to feel part of our social or family group. We give presents to say “I’m sorry.”Sometimes it is difficult for us to find a present that someone will like. Sometimes we give things that we like or would frrl comfortable with. In all these cases, the gifts are sending out messages-often very expressive ones.

64. ___________

People tend to talk about presents in a fairly loving way. A woman whose mother had died years ago described the many gifts around her house.These were gifts that her mother had given her over the years:“I appreciate these, and they mean something to me,”the woman said,“because I remember the occasions they were given on, and that they were from my mother, and the relationship we’ve had.”The gifts remain and keep the relationship alive in mind. This woman felt the same way about the gifts she gave to others. She hoped that the recipients would look at here gifts in years to come and

65. _________

Emotions(情感)like these suggest that a positive spirit still lies behind gift giving. They prove that the anthropologist Claude Levi-Strauss was wrong to say that modern western gift giving is highly wasteful. Studies in Canada and elsewhere have also shown that this is not the case. Each gift is unique even if so many are given.The emotional benefit for those who exchange gifts is the very reason for the tradition to continue.

题型:填空题

女,30岁。患甲状腺功能亢进多年,拔牙注意事项中,错误的是

A.基础代谢率在+20%以下
B.必要时请内科医生监护
C.麻药中加少量肾上腺素
D.脉搏100次/分以下
E.采取预防感染措施

题型:填空题

什么是财务活动?

题型:填空题

某黄色微透明材料,比重是1.08,折射率近1.54,在饱和盐溶液中不下沉,用乙醚作用不变粘,它应该是:()

A.琥珀

B.塑料

C.硬树脂

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