在物理学中，磁场的强弱用磁感应强度（用字母B表示，国际单位是特斯拉，符号是T）来表示，磁感线越密的地方，磁场越强，磁感应强度B越大.

（1）在图20中，甲为某磁极附近磁感线的方向和分布的示意图，由图可知，该磁极为 ▲ 极，若在l处放置一个小磁针，当小磁针静止时，其指向应是图乙中的  ▲   .
（2）磁敏电阻阻值的大小随磁场的强弱变化而变，图丁是某磁敏电阻R的阻值随磁感应强度B变化的图象，据图线可知，磁敏电阻的阻值随磁感应强度B的增大而▲ ．图线没有过坐标原点，说明  ▲  .
（3）王强设计了一个可以测量该磁敏电阻R的电路如图丙所示，（其中磁敏电阻所处的磁场未画出）．将该磁敏电阻R放置在磁场中的位置某处，测出电阻后，利用R—B特性曲线可以读出相应的磁感应强度.
①在图甲磁场中1处，测得的数据如图20表中所示，则该磁敏电阻的测量值为 ▲ Ω. 
②根据该磁敏电阻的R-B特性曲线可知，1处的磁感应强度为   ▲    T.
③在实验过程中，仅将磁敏电阻从1处移至2处，其它条件不变，那么电流表的示数
▲   （填“增大”、“减小”或“不变”）.
④依据上述方法获得的磁感应强度B的测量值与该点实际值存在不小的误差，为尽可能准确反映空间某点磁场的强弱，你认为在选择磁敏电阻时应注意什么问题？

任务性阅读

先阅读(A)、(B)两篇短文，然后根据题目要求及所给语境完成下列四项任务。

certain    we    confident    something    communication

     How can we practice our spoken English ? The first and the most important thing is to believe yourself . You should always be full of   1  . You should often encourage yourself. “Come on , don’t be afraid !” You should never lose heart and never give up.

Maybe you are afraid of losing face, but you should think since we are students and we are learning, there is no need to worry about   2  . We must always be active in practice. We should    3   with our classmates as often as possible in English. We must know that the main way to study English is that we should make   4   understood. We should believe that native speakers will not laugh at us, instead they will encourage us. So if we are brave enough, we’ll   5  make much progress in our spoken English. Don’t be shy or afraid! Just have a try.

(B)

People started wearing clothes to protect themselves from the sun, wind, rain and cold. People said that many years ago the first kind of clothes were made of animal skins. Today we use different materials.

But clothes do more than keep us warm. Our clothes can also tell about who we are, our culture, life and hobbies. For example, if we like to wear yellow or pink clothes, we are usually active and easy--going. If we like black and blue, we may be quiet people. As a middle school student, we often wear the school clothes. Someone who works in a bank may wear a suit every day.

1.用方框中所给词的适当形式填空，使文章通顺、连贯、合理。（每空一词，每词限用一次）

1.__________2 .__________ 3.__________4.__________5.__________

2.根据英文释义及首字母提示，拼写单词。

6. c__________ education, area, literature and so on

7. a__________ full of action

3.同义句转换，每空一词。

People said that many years ago the first kind of clothes were made of animal skins.

It 8._________9._________ that many years ago the first kind of clothes were made of animal skins.

4.根据短文内容简答问题。

10. If someone likes wearing black and blue, what kind of person is he?

______________________.

 

 

 

Photo  regular  good   keep   that

 

Every person needs friends. Friends are __1.__ who open their hearts to us. They always encourage us to try our __2.__ to do everything, and they even make us face challenges bravely. __3.__ in touch with our friends is important to us all. In this way, we can know how everything is going on with our friends. Friends communicate with each other in different ways. Some make phone calls to their friends __4.__. Some send postcards to their friends when they go on holiday. Others prefer to send interesting articles and __5.__ along with their letters. Among the ways, there must be your favorite one. Anyway, let’s communicate with our friends as often as possible.

 (B)

Music touches our hearts and shortens (缩短) the distance between people of different countries. The super star Jay Chou has cooperated with the American NBA star Kobe Bryant to create a song named The Heaven and Earth Challenge. That’s a song written by Jay Chou whose favorite sport is basketball. It expresses the love for basketball. And it encourages young people to be more confident. Jay Chou has learned much from Kobe’s sports spirit. In the song, Jay Chou does most of the singing part while Kobe plays a part of rapper (说唱者). People can download the ring tone (铃声) of the song from the Internet. All the money from the downloads will go to Project Hope, which aims to improve educational environment in poor areas in China.

任务1. 用方框里所给的单词的适当形式填空，使文章通顺、连贯、合理（每词限用一次）

任务2. 根据英文释义及首字母提示，拼写单词。

6.d__________: space between two points or places

7.e__________: give confidence or hope to somebody

任务3.同义句转换，每空一词。

Jay Chou has learned much from Kobe’s sports spirit.

Jay Chou has learned 8.______ 9.______ from Kobe’s sports spirit.

任务4. 根据短文内容简答问题。

10.What does the song express?

_________________________________

 

用如图所示器材测滑轮组的机械效率。

（1）在图上画出滑轮组最省力的绕线方式。
（2）安装好实验器材后，记下钩码和拴住弹簧测力计的线端原先的位置，
（3）某同学正确测得钩码上升的高度为0.2m，钩码重1.5N，其他被
测和计算的数据如下表：

拉力F/N	拉弹簧测力计的线端通过距离S/m	有用功W有用/J	总功W总/J
0.6	0.4	0.3	0.24

上表中肯定错误的数据是            和          。
（4）若用上述装置提起重1.5N的钩码，机械效率为?₁；提起重3N的钩码，机械效率为?₂，则?₁      ?₂（填“>”、“<”或“=”）

书面表达

一个美国中学生代表团将来你校交流学习，并与你校学生座谈。请根据表格中的内容用英语写一篇发言稿，介绍你校学生开展小组学习和自主学习（study by oneself）的情况。

学习方法	做法
小组合作学习	1.互相帮助；2.与他人合作；3.分享（share）他人观点。
自主学习	1.合理安排时间；2.高效地(efficiently)学习；3.学习的主人(major roles)。

 

要求:1. 用上所有提示，可适当发挥；

2. 语言正确，行文流畅，书写规范；

3．词数：80左右。发言稿开头已给出；

4．文中不能出现真实姓名及校名。

Dear friends,

Welcome to our school!  I’d like to talk about two ways of study used in our school.

                                                                                    

                                                                                    

                                                                                 

                                                                                

Thank you.