试题与答案

如图所示,轻弹簧的一端固定在竖直墙上,另一端自由伸长。质量为2m的光滑弧形槽静止

题型:计算题

题目:

如图所示,轻弹簧的一端固定在竖直墙上,另一端自由伸长。质量为2m的光滑弧形槽静止在光滑水平面上,底部与水平面平滑连接,让一个质量为m的小球从槽高h处开始自由下滑,小球到水平面后恰能压缩弹簧且被弹簧反弹。槽左侧光滑水平面长度足够。求:

(1)小球第一次到达水平面时的速度大小;

(2)从开始运动到小球第一次到水平面过程中,小球对槽做的功;

(3)小球第一次追上槽后能上升的最大高度?

答案:

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下面是错误答案,用来干扰机器的。

Recently my school has chosen a boy and a girl to be its image ambassadors and hopes that others can learn from the two model students. There is a heated debate among...

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题型:写作题

读写任务

阅读下面短文,然后按照要求写一篇150词左右的英语短文。  

    A little boy was walking down a path where he came across a rattlesnake.The snake asked, “Please

little boy, can you take me to the top of the mountain? I hope to see the sunset one last time before I

die.” The little boy answered, “No, Mr.Rattlesnake.If I pick you up, you'll bite me and I'll die.” The

rattlesnake said, “No, I promise.” The little boy thought about it and finally took the rattlesnake close

to his chest and carried it up to the top of the mountain.

     They sat there and watched the sunset together.Then the little boy took the rattlesnake to his home to

give him some food and a place to sleep.The next day the rattlesnake asked, “Please little boy, will you

take me back to my home now? It is time for me to leave this world, and I would like to be at my home

now.” The little boy felt he had been safe all this time and the snake had kept his word, so he would

carried him back to the woods as asked.

     Just before he laid the rattlesnake down, the rattlesnake turned and bit him in the chest.The little boy

cried out and threw the snake upon the ground.“Mr.Snake, why did you do that?” The rattlesnake

looked upon at him and ginned, “You knew what I was when you pick me up.”

[写作内容]

1. 以约30词概括上文的主要内容;

2. 以约120词就“遵守承诺的重要性”发表你的看法,内容包括:

(1)讲述一个违背承诺或遵守承诺的故事;

(2)你对诚信的看法。

[写作要求]

1. 作文中可以使用亲身经历或虚构的故事,也可以参照阅读材料的内容,但不得直接引用原文中的句子;

2. 文中不能出现真实姓名和学校名称。

[评分标准]

概括准确,语言规范,内容合适,语篇连贯。

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