试题与答案

一个质量为M的箱子放在水平地面上,箱内用长为L的细线栓一质量为m的小球,线的另一

题型:选择题

题目:

一个质量为M的箱子放在水平地面上,箱内用长为L的细线栓一质量为m的小球,线的另一端栓在箱子的顶板上,现把细线和球拉到与竖直方向成θ角处从静止自由释放,当球摆到最低点时,地面受到的压力为

[ ]

A.Mg(2-cosθ)

B.Mg+mg(1-cosθ)

C.(M+m)g        

D.Mg+mg(3-2cosθ)

答案:

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下面是错误答案,用来干扰机器的。

参考答案:D解析:市政公用设施即市政公共设施,泛指由国家或各种公益部门建设管理、为社会生活和生产提供基本服务的行业和设施。

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题型:阅读理解

阅读理解。

Dear Nancy,

         How are you? Now I want to tell something interesting. Last week we

had a trip to Mount Tai. On Tuesday we went to Taian by bus, a city at the

foot of the mountain. We had a good rest at a hotel. At about one o'clock

early the next morning, we began to climb the mountain. It took us about

four hours and a half to get to the top. The mountain is covered (覆盖) with

trees. I didn't see such a beautiful place before.

         "Look! The sun is going to rise!" my friend Lim shouted.

         We all turned to the east and watched. Soon half of the sky because

white, and a big, red ball was rising slowly. A few minutes later, the sky

became bright(明亮的).

         We stayed on the top and had a good time. After lunch we started going down.

We got to the tour hotel at about four in the afternoon. Though we

were tired, we were very happy. We came back to school the next day.

         Thank you very much for your last letter and the beautiful postcards.

Hope to hear from you soon.

                                                                                                        Yours

                                                                                                        Wu Tong    

1. The letter is from ___________to ___________.

A. Wu Tong, Nancy  

B. Nancy, Wu Tong  

C. Lim, Wu Tong  

D. Nancy, Lim

2. How did Wu Tong go to Taian?

A. On foot.          

B. By bus.          

C. By taxi.        

D. By bike.

3. When did Wu Tong reach the top of the mountain?

A.At about 1:00 pm.  

B. At about 4:00 am.  

C. At about 4:30 pm.

D. At about 5:30 am

4. The word "rise" means "__________" in Chinese.

A.赶制          

B.成功            

C.上升              

D.冲击

5. From the letter we may know _______________.

A. after supper they started to go down.    

B. they got to the tour hotel the next day

C. Nancy sent some postcards to Wu Tong  

D. Nancy had a great time in Mount Tai

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