问题 选择题

用照相机拍照片时,正确的说法是(  )

A.因为要得到倒立放大的实像,所以镜头要用凸透镜,人要离镜头很近

B.因为要得到倒立缩小的实像,所以镜头要用凹透镜,人要离镜头很近

C.因为要得到倒立缩小的实像,所以镜头要用凸透镜,人要离镜头较远

D.因为要得到正立放大的实像,所以镜头要用凸透镜,人要离镜头较远

答案

照相机的镜头是一个凸透镜,它是利用物距大于凸透镜的二倍焦距时,物体在凸透镜中成倒立缩小的实像这种情况制成的,所以物体距离镜头要远一些.

故选C.

阅读理解

阅读理解。

     When the earthquake hit Japan on March 11, 2011, workers in a supermarket in Japan didn't run away

  when they felt the shaking. Instead, they held on to the shelves and tried to stop the goods from falling

 down.

     Reporters from NHK, the country's largest TV station, stayed calm in front of cameras during the earth

 quake, even though some were facing real danger.

     The earthquake was the most powerful one to hit Japan in the country's history. But Japan's reaction to

  the earthquake has shown that it is the most earthquake-prepared (有准备的) country in the world. The

  calm that Japanese showed during and after the quake has impressed the world.

     This is because Japan has an earthquake culture. Japanese people are taught how to prepare for and

  react to an earthquake from a young age.

     One way kids learn about earthquake safety is from the cartoon character Maruko, a 9-year-old

 student. In Chibi Maruko-Chan (《樱桃小丸子》), Maruko has to wear a protective (防护的) hat in

 an earthquake practice. Schools in Japan organize earthquake practices every month. They make students

  become familiar (熟悉的) with being in an earthquake.

     Japan also has a good earthquake warning (警报) system. Warnings were broadcast on TV, the radio

  and cell phones eight seconds after experts first knew about the quake on March 11. The warning system

  is unable to predict an earthquake, but it can usually alert (提醒) people about 15 seconds before they

 feel the effects. Even 15 or 20 seconds can be enough to save people's lives.

1. When the big earthquake happened in Japan on March 11, ______.

    A. people stayed calm

    B. people were too scared to move

    C. people ran outdoors in a hurry  

    D. people escaped from the country at once

2. From this passage, we know that NHK is a _____ in Japan. 

    A. bus stop    

    B. TV station  

    C. famous movie  

    D. five-star restaurant  

3. What does the underlined word "reaction" mean in Chinese?

    A. 影像      

    B. 动作      

    C. 反应        

    D. 保护

4. What can we learn from the passage?

    A. Earthquake practices in Japan are very common.

    B. Japan has a warning system that can predict earthquakes.

    C. Few people were hurt during the Japan earthquake on March 11, 2011.

    D. Japanese kids learn about earthquake safety only from school earthquake practices.

5. Which is the BEST title for the passage?

    A. How terrible the earthquake is

    B. Japan's earthquake culture

    C. Japanese people are very brave

    D. The earthquakes can be predicted

单项选择题