问题 问答题

小明学习小组同学在做《探究凸透镜成像的规律》实验过程中,按操作步骤进行调整,在调整过程中,他们发现光屏上承接烛焰的像偏上,如图,则应______(向上/向下)调整光屏.将凸透镜正对太阳光,在透镜的另一侧移动光屏,在距透镜10cm处,屏上呈现出最小最亮的光斑,若将烛焰移至距凸透镜 15cm 处,移动光屏,使烛焰在屏上得到倒立、______清晰的实像.(选填:“缩小”、“放大”或“等大”)

答案

(1)光屏上承接烛焰的像偏上,要想让像成在光屏的中央,应当将光屏向上移动;

(2)凸透镜正对太阳光,在透镜的另一侧移动光屏,在距透镜10cm处,屏上呈现出最小最亮的光斑,这个光斑就是焦点,该凸透镜的焦距为10cm;

(3)烛焰移至距凸透镜 15cm 处,此时烛焰位于1倍焦距和2倍焦距之间,根据成像规律,光屏上成倒立、放大的实像.

故答案为:上、放大.

阅读理解

第三部分阅读理解(共20小题;每小题2分,满分40分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项,并在答题卡上将该项涂黑。

A

This week in our Foreign Student Series,we talk about getting an American education online.A student named Hendra has written to us from Indonesia asking about a good online university.Finding the right online program requires research.Talking to advisers and recruiters(招募者)can help.Keep in mind,though,that they might have a financial interest to direct you to certain programs.

The Council on Higher Education Accreditation(CHEA)recognizes a group in Washington,D.C.,to accredit(授权)schools that offer distance learning.One hundred and ten programs in the United States and six other countries are accredited by the Distance Education and Training Council.

We asked the executive director,Michael Lambert,for advice on choosing a distance learning program.He says the first thing is to go on the CHEA Web site to find if a school is accredited.The address is c-h-e-a dot o-r-g.Next,make sure the school offers what you need.Do you need a degree,or will a certificate or license be enough?

Another consideration is cost.Often the published price does not include all the costs --like books.Technology requirements can also add to the costs.Will you need to get new software or a high-speed Internet connection or even a new computer to take the classes you want?

Also,consider the level of interaction that an online program offers.You might never meet the teacher or other students in person.

Finally,and this is our own advice,find out what others say on the Internet for comments or news stories about schools that interest you.Just remember that what people say is not always fair or true.

56.This passage is probably from ________.

A.a magazine          B.a newspaper    

C.a text book       D.a radio program

57.This passage is mainly about ________.

A.how to get an American education online

B.what to learn in an American university

C.the introductions to schools offering distance learning

D.the advantages of online education

58.What else should be taken into consideration about cost besides the published price?

A.The cost for books and technology requirements.

B.The cost for books and a new computer.

C.The cost for new software and a high-speed Internet connection.

D.The cost for technology requirements and even a classroom.

59.How can you find the information about schools accredited to offer distance learning easily?

A.Ask the members of CHEA.        B.Go on the website of chea.org.

C.Ask Michael Lambert for help.      D.Talk to advisers and recruiters.

60 According to Michael Lambert,________.

A.to get a certificate or a license is much easier than to get a degree

B.it’s not fair for the schools to charge extra money beside the published price

C.the level of interaction that an online program offers is quite considerable

D.people’s comments about schools are always unbelievable

单项选择题