问题 单项选择题

意大利科学家伽利略在研究物体变速运动规律时,做了著名的“斜面实验”,他测量了铜球在较小倾角斜面上的运动情况,发现铜球做的是匀加速直线运动,且铜球加速度随斜面倾角的增大而增大,在当时的年代由于加速度增大而导致时间无法测定,于是他对大倾角情况进行了合理的外推,由此得出的结论是()

A.自由落体运动是一种匀加速直线运动

B.力是使物体产生加速度的原因

C.力不是维持物体运动的原因

D.物体都具有保持原来运动状态的属性,即惯性

答案

参考答案:A

解析:铜球在较小倾角斜面上的运动情况,发现铜球做的是匀变速直线运动,且铜球加速度随斜面倾角的增大而增大,倾角最大到90°时,这时物体做自由落体运动,由此得出的结论是自由落体运动是一种匀变速直线运动.

单项选择题
阅读理解

阅读理解。

     Loma just had to get in touch with someone:"I had to tell my best friend something important. I tried

calling her but I couldn't get through. So I sent her an e-mail and then I spoke to her on MSN. Without

technology I would not have been able to tell her. "

    Staying connected with friends and family is important for us. That's why we asked our readers to tell

us how cell-phones, e-mail, blogs, text messaging, and personal pages help them keep in touch. More

than 1,500 responded.

     Most of them told us they couldn't live without technology:80%of teens said they need technology to

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other methods of communication.

     What do they do when they've got news they need to share now? Most teens say they try to reach

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words out.

     Lots of people use one way of communication-like text messaging-to get a friend's attention and then

use another where they can talk more. "My friends and I always tell each other everything that happens.

So I send them text messages to tell them to come online so we can talk about it," said Sabeiha.

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text messaging allows you to send the same message to as many as you'd like, which saves a lot of time. "

1. Which of the following is NOT mentioned in the passage?

A. E-mails.    

B. Blogs.        

C. Personal pages.    

D. Personal letters.

2. What do most young people use first when they have news to tell their friends?

A. MSN.      

B. QQ.           

C. Phones.          

D. Text message.

3. The underlined part "get the words out" means"      ".

A. send the message              

B. send the e-mail

C. talk with their friends            

D. meet their friends

4. In which part of a newspaper can you find this passage?

A. Sport.      

B. Education.    

C. Technology.      

D. Culture.