[题目]2016年6月25日20时00分07秒.长征七号运载火箭从海南文昌航天发射中心首次发射.成功将载荷送入预定轨道.任务取得圆满成功.如图所示.长征七号多级火箭发射时.第一级火箭点火后.使卫星向上匀加速运动的加速度为50 m/s2.燃烧30 s后第一级脱离.第二级火箭没有马上点火.所以卫星向上做加速度为10 m/s2的匀减速运动.10 s后第二级火箭启动.卫星题目和参考答案——青夏教育精英家教网—

题目内容

【题目】2016年6月25日20时00分07秒，长征七号运载火箭从海南文昌航天发射中心首次发射，成功将载荷送入预定轨道，任务取得圆满成功。如图所示，长征七号多级火箭发射时，第一级火箭点火后，使卫星向上匀加速运动的加速度为50 m/s2，燃烧30 s后第一级脱离，第二级火箭没有马上点火，所以卫星向上做加速度为10 m/s2的匀减速运动，10 s后第二级火箭启动，卫星向上的加速度为80 m/s2，这样经过1分半钟第二级火箭脱离时，卫星的速度多大？

请你用v-t图象描述这一过程。

【答案】8 600 m/s；如图所示

【解析】整个过程中卫星的运动不是匀变速直线运动，但可以分为三个匀变速直线运动处理。

第一级火箭燃烧完毕时的速度

v1＝a1t1＝50×30 m/s＝1 500 m/s

减速上升10 s后的速度

v2＝v1－a2t2＝1500 m/s－10×10 m/s＝1 400 m/s

第二级火箭熄火时的速度

v3＝v2＋a3t3＝1 400 m/s＋80×90 m/s＝8 600 m/s。

“v-t”图象如图所示。

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假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏字符号(∧)，并在其下面写出该加的词。

删除：把多余的词用斜线(＼)划掉。

修改：在错的词下画一横线，并在该词下面写出修改后的词。

注意：

1. 每处错误及其修改均仅限一词；

2. 只允许修改10处，多者(从第11处起)不计分。

Which is known to all, nowadays the Internet is playing more and more important part in our daily life. In it, we can not only read news at home and abroad but also get so much information as possible. We are often send e-mails to our classmates. We can make telephone call to our families as well as our friends. However, we can go to school on the net, read different kinds of books and even teach myself English. We can also enjoy music, watching sports and play computer games on the Net. We could do shopping even without leaving our homes.

【题目】B

Katharine Graham, once described as ＂the most powerful woman in America＂, was the owner and publisher of The Washington Post newspaper. Under her leadership, it became one of the most important newspapers in the country.

Katharine Graham was born in New York in 1917. Graduating from the University of Chicago in 1938, Katherine got a job as a reporter for a newspaper in San Francisco, California. In 1933, Katharine’s father bought a failing newspaper, The Washington Post. It was the least successful of five newspapers in Washington.

Soon Katharine returned to Washington and got a job editing letters to the editor of her father’s newspaper. In 1946, her husband Philip Graham became publisher of The Washington Post. When she was 46, her husband died, leaving Katharine Graham four children to raise and a newspaper to operate.

At first, she was concerned only with finding a way to keep control of The Washington Post until her sons were old enough to lead it. She had no training in business or experience in operating a large company and decided to learn. She hired excellent reporters and editors. In 1969, Missus Graham became publisher as well as president of The Washington Post company. In the 1970s, The Washington Post became famous around the world. Katharine Graham also played an important role in supporting women by employing more of them. When she was eighty years old, Katharine Graham wrote a very popular book called Personal History about her life, which won a Pulitzer prize for biography in 1998. Friends of Katharine Graham said she used her intelligence and bravery to improve the American media.

【1】 Katharine Graham first worked as ___________.

A. a reporter B. an editor

C. a publisher D. a manager

【2】 When Katharine’s father bought The Washington Post, __________.

A. it had been in business for a short time

B. it was one of the largest newspapers in the US

C. it was in a difficult situation

D. it had enjoyed great success and fame

【3】The most difficult time for Katharine came when __________.

A. her father died

B. her husband died

C. she took control of The Washington Post

D. she returned home to raise her four kids

【4】What can we infer from the passage?

A. The newspaper was failing under Katharine’s control.

B. There were more women editors than men editors in The Washington Post.

C. Katharine probably had a difficult time operating the newspaper at first.

D. Katharine was best known for her book Personal History.

【题目】听下面一段对话，完成五道小题，每小题仅填写一个词。这段对话你将听两遍。

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假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：

1. 每处错误及其修改均仅限一词；

2. 只允许修改10处，多者（从第11处起）不计分。

Dear friends,

It is real a good chance to have met all of you here. We have spent several precious weekend in learning in the English Club. Although we have been members for a short period of times, we have made a great progress. That is because we are all very actively and the activities are not only enjoyable and also helpful. Besides, the foreign teachers here work hard and try his best to make the activities lively and interested. I am very pleased to say that all of us greatly improved our spoken English so far. I am looking forward to see all of you again in the near future!