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2018版高考英语大一轮复习Unit1Alandofdiversity复习练案新人教版选修8

2018版高考英语大一轮复习Unit1Alandofdiversity复习练案新人教版选修8
2018版高考英语大一轮复习Unit1Alandofdiversity复习练案新人教版选修8

Unit 1 A land of diversity

Ⅰ.阅读理解

A

(2016·西北工业大学附中第六次适应性训练)导学号 42492768 When early colonial settlers went to America, they took many forms of dance to their_new_home.Square dancing, one of the oldest forms of American folk dance developed from several different Old World group dances, mainly English country dances and the French quadrille (四对方舞).

In the American version of square dancing,four couples form a square and dance to music.An American addition to square dancing is the caller.What do you think a caller does?

Although popular for years, square dancing seemed to be going out of style and fading away until the early 1930s, when Henry Ford helped revive (复苏) interest in it.Ford, the automobile manufacturer, used to vacation at the Wayside Inn in Massachusetts, where he enjoyed the dance program run by a man named Benjamin Lovett.Ford asked Lovett to come to Detroit and teach dances, but Lovett said he couldn't because he had a contract with the inn.Ford solved that problem by buying the inn and Lovett's contract.He took Lovett back to Detroit, where together they established a program for teaching squares and rounds.Square dancing was updated and groups began forming all over the country.

文章大意:早期的殖民定居者到达美国时把很多形式的舞蹈带到了美国,而方形舞就是其中之一。本文介绍了方形舞的起源和发展。

1.What is the best title for the passage?__B__

A.The Different Steps of Square Dancing

B.The Origin and Development of Square Dancing

C.Who Was the Inventor of Square Dancing

D.Why Did Square Dancing Go Out of Style?

解析:主旨大意题。通读全文可知,第一段介绍了方形舞的起源,第二、三段主要介绍了方形舞的发展,第四段介绍了亨利·福特使得方形舞再次流行起来。故B项“方形舞的起源和发展”最能概括文章主旨。

2.What does the underlined part “their new home” refer to?__D__

A.The United Kingdom. B.France.

C.Africa. D.America.

解析:词义猜测题。根据文章第一段第一句When early colonial settlers went to America,they took many forms of dance to their new home.可知,早期的殖民定居者去美国时把很多形式的舞蹈也带到了他们的新家园。由此可知,their new home在此指的是“美国”。故选D项。

3.Why did the caller call out the steps for the dancers?__D__

A.Because the dance was invented by the caller.

B.Because the dancers didn't know the names of the steps.

C.Because the steps were very particular.

D.Because it was hard for the dancers to remember all the steps.

解析:细节理解题。根据文章第三段第二句...but eventually the dance became so complicated that it was necessary to have someone call out cues so that dancers didn't have to remember so many steps.可知,方形舞中的舞步指挥喊出舞步是为了提醒舞者,从而使舞者不必记住那么多复杂的舞步。故选D项。

4.What can we learn about Henry Ford in the last paragraph?__C__

A.He was the man who made the first car.

B.He was very fond of dancing.

C.He helped make square dancing popular again.

D.He taught people how to dance.

解析:推理判断题。根据文章最后一段第一句...when Henry Ford helped revive interest in it.及下文介绍他是如何做的可知,亨利·福特使得方形舞再次流行起来。故选C项。

B

(2016·蚌埠市一模)导学号 42492769 For example, many retired Americans can be found driving around the United States in big recreational vehicles, known as R.V.'s.These serve as a home away from home.In fact, it might even be their only home as they see the country.

Some American families get in their cars and drive to historic places like Colonial Williamsburg in Virginia.There, they can experience what life was like for early Americans.If that is not exciting enough, also in Williamsburg is a water park and an amusement park with rides.

Other Americans visit national parks like Yellowstone or Yosemite out in the West.They want to spend time with nature.Or they take their vacation by a lake or

the ocean.They might swim or fish.But many just want to sit and enjoy the feeling of doing nothing, except maybe read a book.

Some families fly to other countries on vacation.Or they go on a cruise ship (大型游轮)and stop in different ports.Cruise ships are like floating cities.

But not everyone goes someplace special on vacation.This might be the only time for people to work on things like home improvement projects.And while they do that, they might think of all the fun their friends are having.

文章大意:本文讲述了美国人比其他工业城市的人工作时间多,而休息时间少。当他们休息时,大部分家庭会选择在暑假离开家出去旅游一两周,甚至更长的时间,通过不同的方式去各个地方感受不一样的旅行快乐。

5.What can be the best title for the text?__B__

A.Americans Work More and Vacation Less

B.Where Americans Go on Their Summer Vacations

C.Different Places for Summer Vacations

D.Not All Americans Take Summer Vacations

解析:主旨大意题。本文介绍了在暑假,美国人会花费一两周,甚至更长的时间离开家出去旅游,他们旅游的方式和地点很多,如一些人驾车环游美国、一些人去历史悠久的地方,还有一些人利用假期接近大自然,由此可推断出B项“美国人夏季去哪度假”作为文章标题最佳。故选B项。

6.If you want to spend time with nature, you can do the following things except __D__.

A.to visit national parks B.to see the country

C.to stay by a lake D.to visit historic places

解析:细节理解题。根据文章第四段Other Americans visit national parks like Yellowstone...Or they take their vacation by a lake or the ocean...maybe read a book.可知,如果想接近自然,你可以去参观国家公园,或呆在湖边或去海边玩耍,甚至可以读书。而to visit historic places只是能让人们感受到早期的美国生活,不属于接近自然。故选D项。

7.Which of the following is False?__C__

A.People choose different destinations depending on different interests.

B.People interested in history can have fun in Colonial Williamsburg.

C.All the people take vacations only to do nothing but relax themselves.

D.Not all Americans can afford time and money to go on a vacation.

解析:细节理解题。根据文章最后一段中的But not everyone goes someplace special

on vacation.This might be the only time for people to work on things like home improvement projects.可知,并不是每个美国人都会在假期放松自己去各个地方旅游,有些人也许只有在假期才能进行他们的家庭改进工作。C项中的All the people和only用词过于绝对,C项表述错误,故为答案。

8.What does the underlined sentence of the passage mean?__D__

A.They fully enjoy doing their work on home improvement projects.

B.They think of their work at home as a special kind of vacation.

C.They can imagine what fun their friends are having on vacation.

D.They might envy their friends having time going on vacation.

解析:词义猜测题。根据文章最后一段的描述可知,有的美国人会利用假期做家庭改进的工作,而这些人是不能出去旅游的,由此可推断出画线句表达的是他们可能会羡慕他们的朋友有时间出去旅游。故选D项。

Ⅱ.七选五导学号 42492770

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余项。

(2016·成都市二诊) Some people describe American society as a salad bowl while others think of it as a melting pot.

In a bowl of salad, all the ingredients are mixed together.__1.B__Together, however, the ingredients make up a unity.All the ingredients of a salad contribute to the finished product.They may be covered with the same dressing (调味酱), but the green vegetables, tomatoes and cooked corn can all be seen for what they are.

From this point of view, America is very much like a salad bowl where individual ethnic groups mix together, yet maintain their cultural uniqueness.People may work together during the day at similar jobs and in the same companies, but at night they may return to their ethnic groups where their own individual culture directs their way of life.__2.C__Each ethnic group has its own special customs, language, food and traditions to protect and defend.This idea of the salad bowl is referred to as cultural diversity;that is, American society is a collection of various cultures living together in harmony within one country.

__3.G__Here, society is like one large pot of soup.All cultural aspects are mixed together,sacrificing their original identity and keeping a bit of what they were to become a new reality.The longer the soup is cooked, the better the taste and the more likely it will be for the mixture to dissolve.In this sense, America can surely

be seen as a melting pot where people from all over the world come to live and work together forming one nation.There are dozens of shared symbols.__4.F__In such a culture, symbols like the flag and the nation's official song serve to break down the walls which separate ethnic groups.

Whether a salad bowl or a melting pot, America can be best described as a mixture of both.__5.D__

A.Both are correct depending on one's point of view.

B.They never lose their shapes, colors or tastes.

C.This is why there is so much diversity within America.

D.In other words, America is a nation where there is unity in diversity.

E.Thus, one needs to abandon one's culture to be considered “American”.F.They serve to develop the various ethnic groups to create a new American culture.

G.The other theory, which is also used to describe American society, is the melting pot.

文章大意:有的人把美国社会描述为“沙拉碗”,有的人认为它是“大熔炉”。实际上,美国的特点并非非此即彼,而是在差异中存在统一。

解析:

1.根据设空处前面的 a bowl of salad及本段最后一句,分析各个选项可知,只有B 项“它们从来不会失去它们的形状、颜色和味道”描述的与沙拉有关。They指代前句中的all the ingredients(所有的材料)。故选B项。

2.根据分析,本段继续描述美国像“沙拉碗”,前后为因果关系:“多个民族”融合,但是“保持着各自的独特性”,使得人们白天可能从事相似的工作,但是下班后沿用各自民族的生活方式,这就是美国“多样性”的原因。故选C项。

3.文章第一段提出“沙拉碗”和“大熔炉”两个理论。第二、三两段详细描述了“沙拉碗”理论。设空处位于第四段段首,再根据本段中的one large pot及a melting pot可知选G项,引出下文对第二个理论的描述。

4.本段最后三句围绕shared symbols(共享的符号)展开:有许多“共享的符号”,因而“它们”有助于不同的民族发展以便创造一个新的美国文化,而在这样的文化中,美国国旗和国歌这些符号有助于打破种族分裂的藩篱。F项中They指代前句中的shared symbols。故选F项。

5.本段两句话总结全文:“美国将‘沙拉碗’和‘大熔炉’两大特点融合在一起。‘换句话说’,美国是一个‘多样性中存在统一’的国家”。D项中unity in diversity是第一句中a mixture of both的另一种说法。故选D项。

Ⅲ.短文改错导学号 42492771

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:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。

删除:把多余的词用(\)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。

(2016·宝鸡市二模)

Dear Lucy ,

How is everything going?

You know, I am in Grade Three now.Our school has got a opportunity to help us apply to Columbia University, a world -famous university located in the north of America.Those whose pass the selective test held by our school next week would have the chance to take part in the oral and written exams in English as well as the interview by the CU teachers next January.

It has long be my dream to study abroad, I treasure this chance very much.Now, I am trying my best to getting ready for the coming exams.Could you give me some advices on how to get good equipped with English knowledge before exams ?I believe I will benefit a lot of from your valuable and timely suggestions.

I'm looking forward to your reply.

答案: Dear Lucy ,

How is everything going?

You know, I am in Grade Three now.Our school has got a an

opportunity to help us

apply to for

Columbia University, a world -famous university located in the north of

America.Those whose who pass the selective test held by our school next week would will

have

the chance to take part in the oral and written exams in English as well as the interview by the CU teachers next January.

It has long be been my dream to study abroad, ∧so/and

I treasure this chance very

much.Now, I am trying my best to getting get

ready for the coming exams.Could you give me some advices advice on how to get good well

equipped with English knowledge before exams ?

I believe I will benefit a lot of from your valuable and timely suggestions.

I'm looking forward to your reply.

1.解析:第一处:a→an opportunity 的读音以元音音素开头,其前用不定冠词an 。故将a 改为an 。

3.解析:第三处:whose→who Those 后为定语从句,先行词为Those ,且在从句中作主语,指人,应用who 引导。故将whose 改为who 。

4.解析:第四处:would→will 全文时态是一般现在时,根据时间状语next week 可知,应用一般将来时。故将would 改为will 。

5.解析:第五处:be→been 现在完成时have done 结构中,动词要用过去分词形式,故将be 改为been 。

6.解析:第六处:在I 前加so/and 句意为:出国学习一直以来都是我的梦想,因此/而且,我非常珍惜这次机会。根据句意可知,上下文之间是因果关系,或顺承关系,故用连词so/and 连接。

7.解析:第七处:getting→get try one's best to do...意为“尽某人最大努力做……”,其中to 为动词不定式符号,因此应用动词原形。故将getting 改为get 。

8.解析:第八处:advices→advice advice 是不可数名词,没有复数形式。故将advices 改为advice 。

9.解析:第九处:good→well 修饰动词应用副词形式,故将good 改为well 。

10.解析:第十处:删除of 本句中a lot 充当副词修饰动词benefit ,a lot of 后加名词表示“许多”。故删除介词of 。

2018高考物理大一轮复习全真模拟试题精编(十)

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2018届高三第二次联考试题(4月) 理科综合(物理部分)含答案

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2018版高考英语(人教通用)大一轮复习-满分必背+

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be concerned with牵涉到……,与……有关 as/so far as...be concerned关于;至于;就……而言 4.power n.能力;力量;权力 The power was cut off and the street was entirely in darkness.断电后街道完全陷入了黑暗。 She was the one who had the power to hire or fire people.有权雇用或解雇人的是她。[快速闪记] (1)come to power上台,当权,表示动作,不能和一段时间连用。 (2)be in power当权,执政,表示状态,可以和一段时间连用。 (3)have the power to do sth 具有做某事的能力、权力 beyond/out of one's power某人力所不能及 5.settle vi.安家;定居;停留vt.使定居;安排;解决 They calmed down and settled their problem soon. 他们镇静下来并很快把问题解决了。 Mr.Wang settled down in America soon after he got there.王先生到美国后不久就定居下来了。 [快速闪记] (1)settle down舒适地坐下;安静下来;定居下来 settle down to sth/doing sth开始认真对待某事;定下心来做某事 (2)settlement n.解决;协议 6.suffer vt.& vi.遭受;忍受;经历 We'll suffer hunger one day if we don't care about the farmland.如果我们不关注农田,将来我们会挨饿的。 [快速闪记] suffering n.痛苦;苦难sufferer n.患病者;受难者 7.pack vi.& vt.捆扎;包装;打行李n.小包;包裹 As soon as I graduated,I packed my bags and moved to the west of China.一毕业我就收拾行李去了中国西部。 A pack of reporters were waiting outside for the latest news.一群记者在外面等待最

2018届高考物理二轮复习转动切割磁感线问题专题卷

100考点最新模拟题千题精练10-9 一.选择题 1. (2018洛阳联考)1831年,法拉第在一次会议上展示了他发明的圆盘发电机(图甲).它是利用电磁感应的原理制成的,是人类历史上第一台发电机.图乙是这个圆盘发电机的示意图:铜盘安装在水平的铜轴上,它的边缘正好在两磁极之间,两块铜片C 、D 分别与转动轴和铜盘的边缘良好接触.使铜盘转动,电阻R 中就有电流通过.若所加磁场为匀强磁场,回路的总电阻恒定,从左往右看,铜盘沿顺时针方向匀速转动,下列说法中正确的是 ( ) A. 铜片D 的电势高于铜片C 的电势 B. 电阻R 中有正弦式交变电流流过 C. 铜盘转动的角速度增大1倍,流过电阻R 的电流也随之增大1倍 D. 保持铜盘不动,磁场变为方向垂直于铜盘的交变磁场,则铜盘中有电流产生 【参考答案】C 【名师解析】根据右手定则,铜片中电流方向为D 指向C ,由于铜片是电源,所以铜片D 的电势低于铜片 C 的电势,选项A 错误;电阻R 中有恒定的电流流过,选项B 错误;铜盘转动的角速度增大1倍,,根据转 动过程中产生的感应电动势公式E =12 BL 2ω,产生是感应电动势增大1倍,根据闭合电路欧姆定律,流过电 阻R 的电流也随之增大1倍,选项C 正确;保持铜盘不动,磁场变为方向垂直于铜盘的交变磁场,则铜盘中没 有电流产生,选项D 错误。

2.如图所示为一圆环发电装置,用电阻R =4 Ω的导体棒弯成半径L =0.2 m 的闭合圆环,圆心为O ,COD 是一条直径,在O 、D 间接有负载电阻R 1=1 Ω。整个圆环中均有B =0.5 T 的匀强磁场垂直环面穿过。电阻 r =1 Ω的导体棒OA 贴着圆环做匀速运动,角速度ω=300 rad/s ,则( ) A.当OA 到达OC 处时,圆环的电功率为1 W B.当OA 到达OC 处时,圆环的电功率为2 W C.全电路最大功率为3 W D.全电路最大功率为4.5 W 【参考答案】AD 3.如图所示,半径为r 的金属圆盘在垂直于盘面的匀强磁场B 中,绕O 轴以角速度ω沿逆时针方向匀速转动,则通过电阻R 的电流的方向和大小是(金属圆盘的电阻不计)( ) A.由c 到d ,I =Br 2ωR B.由d 到c ,I =Br 2ωR

2018届高考英语第一轮知识点达标检测试卷及答案(15份)

第一部分必修一Module 1 Ⅰ. 完形填空导学号58082016 I had worried myself sick over Simon's mother coming to see me. I was a new __1. C__,and I gave an honest account of the students' work. In Simon's case, tthe grades were awfully low. He couldn't read his own handwriting. __2. D__ he was a bright student. He discussed adult subjects with nearly adult comprehension. His work in no way reflected his __3. A__. So when Simon's mother entered the room, my palms(手掌心) were sweating. I was completely__4. D__for her kisses on both my cheeks. “I came to thank you,”she said, surprising me beyond speech. __5. B__me, Simon had become a different person. He talked of how he__6. B__me, he had begun to make friends, and for the first time in his twelve years, he had__7. D__spent an afternoon at a friend's house. She wanted to tell me how grateful she was for the__8. B__ I had nurtured(培养) in her son. She kissed me again and left. I sat, stunned (惊呆), for about half an hour, __9. D__ what had just happened. How did I make such a life-changing difference to that boy without __10. A__knowing it? What I finally came to __11. A__ several months before, when some students were 12. C reports in the front of the class, Jeanne spoke __13. B__,and to encourage her to raise her voice, I had said, “Speak up. Simon's the expert on this. He is the __14. D__ one you have to convince, and he can't hear you in the __15. C__ of the room. ” That was it. From that day on, Simon had sat up straighter, paid more attention, __16. A__ more, and became happy. And it was all because he __17. C__to be the last kid in the last row. The boy who most needed __18. A__ was the one who took the last seat that day. It taught me the most __19. D__ lesson over the years of my teaching career, and I'm thankful that it came __20. B__and positively. A small kindness can indeed make a difference.

2018年高考语文大一轮复习(限时训练):专题十二 文学类文本阅读 (二)散文阅读 学案6 Word版含答案

限时训练 一、阅读下面的文字,完成1~3题。(14分) 把往事调成花色 王健 很多日子是随阳光一起开放的,很多心情也是随花朵一起明媚的。 闲暇的时候,我总喜欢一个人背着相机来往于城市和乡村之间。在一个乡村古老的街道上,我看到了一堵石墙上花开烂漫,眼前一亮,我知道那将会是一个写满故事的小院。 主人是一个戴着眼镜的老者,正用放大镜认真地看着报纸,他坐在门口,A身体有些蜷曲,像棵老藤。很难相信,在这样的村庄里会有这么一个学者一样的老人。他的文雅、淡然,安静和自若的神态,让我感觉他和这些花、这个小院就是一个密不可分的整体。 耳聋,面善,和蔼可亲,很善谈,他生活在自己沉静的世界里,却出现在我的视野中。通过那些花,我知道了他是个95岁高龄的老人,以前做过教师。难怪他身上有股与众不同的味道呢! 他告诉我,墙头上这些艳丽的花是凌霄,已经有几十年的历史了,去年有人想花1 000元买走,他没舍得。他继而又补充道,如果多点儿我就卖掉它,卖些钱好给老伴治病。 数落起这些花就好像数落着自己的子女。这些是兰,这些是莲,这是栀子,这是何首乌……我突然就想起鲁迅先生笔下的百草园,诗情画意里有一段美丽的故事。 然后他便开始数落那些子女,仿佛在数落着自己院里的那些花草。 我很想从这个高寿的老人口中知道幸福的定义。我问幸福是什么,他听不清:什么? 后来他告诉我幸福是“什么”。

我没懂,他笑:什么都是幸福。小时候想上学堂,以为那就是幸福,后来就去了。后来想当教员,以为那就是幸福,后来真就当了教员。退休了,想安养晚年就是幸福,于是有了这满院花香相伴。现在有人能欣赏我的这些花,我也很幸福。 那么你幸福吗?他回答,我满足于我人生的任何一件事情,无论成败得失。就像我养的这些花,花开花谢,它们不会长开不败,却能在最美的时候开放…… 终于明白一个无私、无欲的老人的幸福观。能够像他院中的花一样,顺从自然、与世无争、坦然处世,就是一种美丽和幸福。 他,何尝不是开在这尘世间的一朵浮莲,B甚至是一棵开满花朵的老藤? 他把我当作客人,我把这里当作我内心的家园,仿佛一杯茶汁泼出的茶园,至今梦里尚带几分茉莉香。而且他的花香弥漫的脸,是媚人的,沧桑中写着“生活”两个字。如果你仔细地去读,会读出更多的内容。 赏过凌霄,闻过芝香,也饮过菊花,愿意在这远离世俗的地方喝醉。感觉阳光、童年、往事和爱,还闪亮在老屋的深处,只是感觉偶尔等一个人,是偶然的缘分。在多年后,10年或者20年时给它浇水,叶年年青翠,花年年明艳,而眼睛却暗了…… 人生莫过于此:头发掉了,牙齿没了,眼睛花了,耳朵聋了,内心却十分明亮。如今,往事皆调成这满院的花色,花开了,年年更新,心就是不老的,还有爱和希望,快乐和幸福。 我突然看到那暗淡的老屋里,窗台上竟然摆放着一瓶栀子花!一个年迈老人对生活之爱,远远浓于这满院的花香,我要告诉你那是心香呵!是生命之香! 我独自走在乡间,一位蜷曲的老人,一座破旧的老屋,一些美丽的花,美好的事物走在我的前面,我记得那老人的话:“我要把我的那些花安放在冬天的前面……”

2018届高考物理二轮复习热点2滑块—木板模型学案

热点2 滑块—木板模型 [热点跟踪专练] 1.(多选)如图所示,A 、B 两物块的质量分别为2m 和m ,静止叠放在水平地面上.A 、B 间的动摩擦因数为μ,B 与地面间的动摩擦因数为12 μ.最大静摩擦力等于滑动摩擦力,重力加速度为g .现对A 施加一水平拉力F ,则( ) A .当F <2μmg 时,A 、 B 都相对地面静止 B .当F =52μmg 时,A 的加速度为13 μg C .当F >3μmg 时,A 相对B 滑动 D .无论F 为何值,B 的加速度不会超过12 μg [解析] 当03μmg 时,A 相对B 向右做加速运动,B 相 对地面也向右加速,选项A 错误,选项C 正确.当F =52 μmg 时,A 与B 共同的加速度a =F -3 2 μmg 3m =13μg ,选项B 正确.F 较大时,取物块B 为研究对象,物块B 的加速度最大为a 2=2μmg -32μmg m =12 μg ,选项D 正确. [答案] BCD 2.(2017·江西模拟)如图所示,在水平地面上叠放着质量均为M 的A 、B 两块木板,在木板A 的上方放着一个质量为m 的物块C ,木板和物块均处于静止状态.A 、B 、C 之间以及B 与地面之间的动摩擦因数都为μ.若用水平恒力F 向右拉动木板A ,使之从B 、C 之间抽出来,已知重力加速度为g ,最大静摩擦力等于滑动摩擦力.则拉力F 的大小应该满足的条件是( )

A .F >μ(2m +M )g B .F >μ(m +2M )g C .F >2μmg D .F >2μ(m +M )g [解析] 要使A 能从B 、C 间抽出来,则A 要相对于B 、C 都滑动,所以A 、C 间与A 、B 间都是滑动摩擦力,对A 有a A =F -μmg -μM +m g M ,对C 有a C =μmg m ,B 受到A 对B 的水平向右的滑动摩擦力μ(M +m )g 和地面对B 的摩擦力f ,由于f ≤μ(2M +m )g ,所以A 刚要从B 、C 间抽出时,B 静止不动,即a A >a C 时,A 能从B 、C 间抽出,得F >2μ(M +m )g ,D 对. [答案] D 3.(2017·广州模拟)如图所示,光滑水平面上放置质量分别为m 、2m 和3m 的三个木块,其中质量为2m 和3m 的木块间用一根不可伸长的轻绳相连,轻绳能承受的最大拉力为F 0;质 量为m 和2m 的木块间的最大静摩擦力为12 F 0.现用水平拉力F 拉质量为3m 的木块,使三个木块一起加速运动,下列说法正确的是( ) A .质量为2m 的木块受到四个力的作用 B .当F 逐渐增大到F 0时,轻绳刚好被拉断 C .在轻绳未被拉断前,当F 逐渐增大时,轻绳上的拉力也随之增大,并且大小总等于F 大小的一半 D .在轻绳被拉断之前,质量为m 和2m 的木块间已经发生相对滑动 [解析] 质量为2m 的木块受到5个力的作用,重力、拉力、压力、支持力和摩擦力,则选项A 错误;对三者整体,应用牛顿第二定律有F =6ma ,对质量为m 和2m 的木块整体,同理有,轻绳拉力T =3ma =F 2,隔离质量为m 的木块,有f =ma =F 6 ,可知在轻绳未被拉断前,当F 逐渐增大时,轻绳上的拉力也随之增大,并且大小总等于F 大小的一半,则选项C 正确;当F 逐渐增大到F 0时,轻绳拉力T =F 0 2,轻绳没有达到最大拉力不会被拉断,则选项B 错误;

2018高考英语一轮复习构想 Unit 1 Art课时作业 新人教版选修6

Unit 1 Art Ⅰ.阅读理解 A Here I will introduce some books to you. Cook Yourself Young By (author) Elizabeth Peyton-Jones Want to look and feel 10 years younger? Keen to remove bags under your eyes, and other unpleasant symptoms of ageing? Long to lose weight and stay slim? All you need is to change what you eat and to COOK YOURSELF YOUNG. In her revolutionary new book, Cook Yourself Young, a health expert Elizabeth Peyton-Jones explains how simply by changing the way you cook you can make yourself look younger and live a healthier, more balanced life. Celebrations and Special Days By (author) Ellen Lawrence In Celebrations and Special Days, young readers will join children around the world as they celebrate religious festivals and special family days, such as weddings and coming of age ceremonies. From Holi to Hanukkah, Easter to Ramadan, readers will join families as they prepare special meals, decorate their homes, and take part in the special times that shape our lives. The Story of the Lost Child By (author) Elena Ferrante “Nothing quite like this has ever been published before,” said The Guardian newspaper about the Neapolitan Novels in 2014, “Those Who Leave and Those Who Stay, the third book in the series, was an international bestseller and a New York Times Notable Book of the Year.” Its author was considered as one of the greatest novelists of our time by the New York Times Book Review. This fourth and final installment in the series raises the bar even higher and indeed confirms Elena Ferrante as one of the world's best living storytellers. 【解题导语】本文是说明文,介绍了三本书的相关信息。 1.Which book should you buy if you want to look young? A. Cook Yourself Young. B. Celebrations and Special Days. C. The Story of the Lost Child. D. New York Times Book Review. 答案与解析:A 考查细节理解。根据Cook Yourself Young部分最后一句中的“by changing the way you cook you can make yourself look younger”可知,Cook Yourself Young这本书介绍了如何通过健康的饮食来使人们保持年轻,故A项正确。 2.Who is Celebrations and Special Days intended for? A. Old people. B. All the people. C. Young people. D. Middle-aged people. 答案与解析:C 考查细节理解。根据Celebrations and Special Days部分第一句中的“In Celebrations and Special Days, young readers will join children around the world”可知,Celebrations and Special Days这本书的阅读对象是年轻人,故C项正确。 3.What can we learn about Elena Ferrante? A. She is the greatest novelist in the US. B. Her books sell best at the present time. C. She is the author of Celebrations and Special Days. D. She belongs to the best living storytellers. 答案与解析:D 考查推理判断。根据最后一段中的“and indeed confirms Elena

2018年高考语文大一轮复习(限时训练):专题六选用、仿用、变换句式(含修辞)含答案

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(江苏专用)2019版高考物理大一轮复习 第12单元 原子物理作业手册

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3.古今异义词 (1)若舍郑以为东道主 ... 今义:请客的主人 古义: (2)行李 ..之往来 今义:出门所带的包裹、箱子等 古义: (3)共其乏困 .. 今义:疲劳 古义: (4)微夫人 ..之力不及此 今义:妻子 古义: 答案:(1)东方道路上(招待过客)的主人;(2)出使的人;(3)缺少(的东西);(4)那人,指秦穆公。 4.词类活用 (1)晋军.函陵,秦军氾南( ) (2)越国以鄙.远( ) (3)既东封 ..郑( ) (4)与郑人盟.( ) (5)越国以鄙远.( ) 答案:(1)名词作动词,驻军;(2)名词意动用法,把……当作边邑;(3)名词作状语,在东边;名词使动用法,使……成为疆界;(4)名词作动词,结盟;(5)形容词作名词,边远的地方。 二、文言虚词 1.以 2.而

3.焉 4.其 5.之 答案:1.连词,因为;介词,拿,用;连词,表顺承;连词,表顺承;介词,把。2.连词,才,表顺承;表修饰,连词;表顺承,连词。3.啊,句末语气词,表感叹;疑问代词,为什么;疑问代词,哪里;兼词,于之。4.代词,指代“使者”;代词,指代“那件事”;代词,自己的;语气词,还是,表商量。5.代词,他们,指秦军;结构助词,的;主谓间助词,取消句子独立性,不译;宾语前置的标志,不译。 三、文言特殊句式 1.夫晋,何厌之有( ) 2.以其无礼于晋( ) 3.晋军函陵( ) 答案:1.宾语前置句;2.状语后置句;3.省略句。 四、文言句子翻译 1.是寡人之过也。 译文: 2.越国以鄙远,君知其难也。 译文: 3.焉用亡郑以陪邻? 译文: 4.邻之厚,君之薄也。 译文: 5.若舍郑以为东道主,行李之往来,共其乏困,君亦无所害。

2019届高考物理大一轮复习金考卷:电磁感应(含解析)

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2018届高考物理二轮复习力与天体运动专题卷(全国通用)

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通用版2018高考英语一轮复习第1部分基础知识解读Unit1Friendship.doc

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2018届高考物理二轮复习变质量计算问题专题卷

100考点最新模拟题千题精练14- 6 1.(10分)用传统的打气筒给自行车打气时,不好判断是否已经打足了气.某研究性学习小组的同学经过思考,解决了这一问题.他们在传统打气筒基础上进行了如下的改装(示意图如图甲所示):圆柱形打气筒高H ,内部横截面积为S ,底部有一单向阀门K ,厚度不计的活塞上提时外界大气可从活塞四周进入,活塞下压时可将打气筒内气体推入容器B 中,B 的容积V B =3HS ,向B 中打气前A 、B 中气体初始压强均为p 0,该组同学设想在打气筒内壁焊接一 卡环C (体积不计),C 距气筒顶部高度为h =23 H ,这样就可以自动控制容器B 中的最终压强.求: ①假设气体温度不变,第一次将活塞从打气筒口压到C 处时,容器B 内的压强; ②要使容器B 内压强不超过5p 0,h 与H 之比应为多大. 2.(2016·陕西五校一模)如图所示是农业上常用的农药喷雾器,贮液筒与打气筒用细连接管相连,已知贮液筒容积为8 L(不计贮液筒两端连接管体积),打气筒活塞每循环工作一次,能向贮液筒内压入1 atm 的空气200 mL ,现打开喷雾头开关K ,装入6 L 的药液后再关闭,设周围大气压恒为1 atm ,打气过程中贮液筒内气体温度与外界温度相同且保持不变。求:

(1)要使贮液筒内药液上方的气体压强达到3 atm,打气筒活塞需要循环工作的次数; (2)打开喷雾头开关K直至贮液筒内、外气压相同时,贮液筒向外喷出药液的体积。【参考答案】(1)20次(2)4 L 由理想气体方程得:p1V1=p2V2 解得:V=4 L 打气次数:n=V 0.2 L =20 (2)打开喷雾头开关K直至贮液筒内外气压相同时,p3=1 atm 由理想气体方程得:p1V1=p3V3 解得:V3=V1=6 L 故喷出药液的体积V′=V3-V0=4 L 3.(2016·山西省高三质检) (2)型号是LWH159-10.0-15的医用氧气瓶,容积是10 L,内装有1.80 kg的氧气。使用前,瓶内氧气压强为1.4×107 Pa,温度为37 ℃。当用这个氧气瓶给患者输氧后,发现瓶内氧气压强变为7.0×106 Pa,温度降为27 ℃,试求患者消耗的氧气的质量。

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