课时跟踪训练3
(完整版)Unit3课时跟踪练(三)
课时跟踪练（三）Section ⅣLearning about Language & Using Language一、全练语言点，基稳才能楼高[本课语言点针对练习]Ⅰ.单词拼写1．John is very reliable(可信赖的) — if he says he'll do something, he'll do it.2．Mary enjoyed feeling the warm sand beneath (在……下面) her feet.3．The view (风景) from the top of the tower was wonderful.4．The flames (火焰) were growing higher and higher.5．The weather forecast (预报) says the storm will hit the area at midnight.6．The restaurant is open from 5 pm to midnight (午夜) every day.7．From animals we get such materials as wool (羊毛), leather and furs.8．John was so tired that he fell asleep as soon as his head hit the pillow (枕头)．Ⅱ.单句改错1．The fans poured into the hall and couldn't wait see the famous film star.see前加to2．In my views, there is no need to care too much about your clothes.views→view3．These were so difficult questions that none of us could settle them.so→such4．As usually, I walked the dog along the ually→usual5．I don't want to go to the station alone, so I ask you to go there with company.with→for[本单元语言点温故练习]Ⅰ.单句语法填空1．They are the graduates (graduate) who graduated from Wuhan University and now are playing an important part in our factory.2．If I see him, I will_give (give) him your message.3．After we lost the game, John said that he didn't really care about it.4．The little girl insisted on playing (play) with her brother.5．Teachers asked that every student should attend classes on schedule.6．I dream about/of playing a leading part in a film.7．After graduation, she couldn't wait to_return (return) to her hometown.8．The manager thought he was a reliable (rely) person and told him all about the new plan.9．However hard he may try, he couldn't open the door.10．The flower is pleasant to_smell (smell)．Ⅱ.补全句子1．They planned a holiday in May but they changed_their_minds and went in June.(mind)他们计划在五月去度假，但是他们改变了想法，在六月去的。
2021-2022学年高中英语人教版必修五练习：Unit 3 课时跟踪练(三) Word版含解析
课时跟踪练（三）Section ⅣLearning about Language & Using Language一、全练语言点，基稳才能楼高[本课语言点针对练习]Ⅰ.单词拼写1．The programme brought an instant (马上的) response.2．He looked at the gold with greedy (贪欲的) eyes.3．Learning English requires a lot of motivation (动机); otherwise, one will lose interest in it.4．There is little doubt that recycling (再利用) is good for the environment.5．Jane was soon swallowed (淹没) up in the crowd.6．A tall building was put up where there used to be a desert (沙漠)．7．He is a representative (代表) of a large steel company.8．With the government's aid, those affected by the earthquake have moved to the new settlements (定居点)．9．A new series of simple English reading materials (材料)for middle school students has come out this year.10．The animal is part of nature. If they were separated from human, we wouldn't be able to keep the ecology (生态) balance.Ⅱ.单句改错1．The train picked speed and soon disappeared in my line of sight.picked后加up2．It is so greedy for you to leave none of the cake for everyone else.第一个for→of3．Instant the hero turned up at the meeting, the audience applauded.Instant→Instantly4．The reason why he was absent from the meeting was because he was delayed by theaccident.because→thatⅢ.补全句子1．They are broadening the bridge to_speed_up the flow of traffic.他们正在拓宽大桥，以加速车流。
高中语文课时跟踪检测(三)+贺+新+郎+Word版含解析.doc
课时跟踪检测（三）贺新郎一、诗歌阅读鉴赏(一)课内阅读阅读《贺新郎》一词，完成1～3题。
1．本词上片“眼角眉梢都似恨，热泪欲零还住”写的是谁？表现了他(她)什么样的性格？答：________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 参考答案：这两句是对杨开慧的刻画描写。
杨开慧当时上有老母需要照顾，下有婴儿需要抚养，革命工作又不能放下，丈夫又要为国事冒着风险远行，心里怎不充满悲伤和担心呢？但她却“热泪欲零还住”，表现了她以革命事业为重的坚强性格。
2．“今朝霜重东门路，照横塘半天残月，凄清如许”运用了什么手法？有什么表达效果？答：________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 参考答案：词句使用了双关的手法。
2019年英语新同步人教必修二精练：Unit 5 课时跟踪练(三) Word版含答案
姓名，年级：时间：课时跟踪练(三) Learning about Language ＆Using Language一、全练语言点，基稳才能楼高［本课语言点针对练习］Ⅰ.单词拼写1．My uncle wears a heavy beard （胡须）. He often shaves it in the office。
2．We are all affected by his total devotion (热爱） to his work。
He has hardly no time to take exercise。
3．Let’s go to the theatre first and eat at a restaurant afterwards （后来）．4．Thanks for your invitation (邀请） to the dance party。
5．The little boy was hurt falling off his bike， and now his shoulders are still painful (疼痛的）．6．Dip (浸；蘸） your hand in to see how hot the water is。
7．Mary explained what we were to do in brief (简短的）．8．Winning the Olympic title has not just brought her fame （名誉) and fortune。
Ⅱ.单句改错1．There are all sort of shops in this area。
sort→sorts2．To be briefly， I think we should accept their invitation.briefly→brief 3．The dictionary is a useful tool with that you can improve your English。
课时跟踪检测( 三 ) 生命活动的主要承担者——蛋白质
课时跟踪检测( 三)生命活动的主要承担者——蛋白质一、单项选择题1．(2020·天河区模拟)与半胱氨酸相比，同型半胱氨酸R基中的巯基(—SH)前多一个“—CH2—”，含同型半胱氨酸的多肽链容易在内质网中形成未折叠蛋白。
据此判断，下列说法正确的是()A．未折叠蛋白与双缩脲试剂不能发生紫色反应B．同型半胱氨酸与半胱氨酸的区别是羧基数目不同C．同型半胱氨酸与其他氨基酸之间不能正常形成肽键D．人体内同型半胱氨酸积累可能影响细胞间的信息交流解析：选D蛋白质与双缩脲试剂反应的原理是双缩脲试剂与其中的肽键反应呈紫色，蛋白质结构是否折叠都会与双缩脲试剂反应呈紫色，A错误；同型半胱氨酸与半胱氨酸的区别是羧基数目相同，R基组成不同，B错误；同型半胱氨酸与其他氨基酸之间也能正常形成肽键，C错误；人体内同型半胱氨酸积累导致蛋白质的空间结构改变而引起胞内紊乱，所以可能影响细胞间的信息交流，D正确。
2．(2020·吴忠模拟)蛋白质是细胞内重要的大分子物质，是生命活动的主要承担者。
下列关于蛋白质的叙述，不正确的是()A．蛋白质多种多样是由于构成蛋白质的氨基酸有多种且数量成百上千B．蛋白质的氨基酸排列顺序是由核酸分子上碱基的排列顺序决定的C．蛋白质的生物合成需要DNA、RNA和多种酶的参与D．在食盐作用下析出的蛋白质空间结构不会发生改变解析：选A蛋白质多种多样是由于构成蛋白质的氨基酸种类、数目、排列顺序不同，且肽链盘曲折叠形成的空间结构不同，A错误；基因控制蛋白质的合成，蛋白质的氨基酸排列顺序是由核酸分子上碱基的排列顺序决定的，B正确；蛋白质的生物合成需要DNA、RNA 和多种酶的参与，C正确；食盐作用下析出的蛋白质的空间结构并没有发生改变，D正确。
3．(2020·泰安四模)哺乳动物成熟红细胞的主要功能是运输氧气，除水分以外，其组成成分中90%是血红蛋白。
下列叙述错误的是()A．缺铁会影响血红蛋白的合成导致贫血B．血红蛋白不适合用双缩脲试剂进行显色反应检测C．从成熟的红细胞中提取到的磷脂几乎全部来自细胞膜D．成熟红细胞吸收葡萄糖时需通过无氧呼吸提供能量解析：选D Fe2＋是构成血红素的元素，血红蛋白是由珠蛋白和血红素结合而成，故缺铁会影响血红蛋白的合成导致贫血，A正确；血红蛋白本身有颜色，会影响实验结果的观察，故血红蛋白不适合用双缩脲试剂进行显色反应检测，B正确；成熟的红细胞没有细胞核，也没有其他细胞器，但是有细胞膜，故从成熟的红细胞中提取到的磷脂几乎全部来自细胞膜，C正确；成熟红细胞吸收葡萄糖的方式是协助扩散，需要载体蛋白，不消耗能量，故不需通过无氧呼吸提供能量，D错误。
2021-2022学年高中英语人教版必修3习题：Unit 5 课时跟踪练(三) Word版含答案
课时跟踪练(三) Learning about Language & Using Language一、全练语言点，基稳才能楼高[本课语言点针对练习]Ⅰ.单词拼写1．Mr. Smith was pleased (欣喜的) that his father was being taken care of in the Home of the Aged.2．Frank made a good impression (印象), so the manager gave him the job.3．If you add too much liquid, the mixture (混合物) will not be thick enough.4．The rumours of an attack were confirmed (证明) later.5．Lin Tao, who is one of my old schoolmates (校友), has been promoted to captain.6．Hard work accounted for his success and wealth (富有)．7．The plane will be landing in approximately (大约) 20 minutes.8．Most girls are terrified (可怕) at snakes and mice, both of which look very ugly.9．It was a misty (有雾的) morning, but it soon became clear when the sun began to shine.10．The traditional (传统) breakfast in this area includes bacon and eggs.Ⅱ.单句语法填空1．Books on Scottish history were mixed up with books on volcanoes.2．The latest evidence confirmed us in his theory.3．The suit cost approximately (approximate) three hundred dollars.4．Although he has become wealthy (wealth), Mr Wood remains what he used to be, modest and friendly.5．I am pleased to_be_invited (invite) to give a lecture on astronomy.6．When the lost boy saw the smoke rising in the distance，he became excited immediately.7．They were terrified by/at his sudden appearance.8．The accident happened on a cold frosty (frost) morning.9．Linda said she would meet Tom andthat she wouldn't tell anyone about the appointment.Ⅲ.补全句子1．It_has_been_confirmed_that we will have a meeting next Monday.已经确定我们下周一要开会。
2021-2022学年高中英语译林版必修三习题：Unit 1 课时跟踪练(三) Word版含答案
课时跟踪练(三) Word power, Grammar and usage & Task一、全练语言点，基稳才能楼高Ⅰ.单词拼写1．They are looking at ways of reducing (削减) the waste of natural resources.2．Some students from Grade 3 volunteered (自愿) to do some cleaning for the elderly people yesterday.3．The teacher tried to analyse (分析) the cause of our failure.4．He recognized (辨认出) the coast of England through a veil of mist.5．The student was puzzled (迷惑) about what to do next.6．If there's one meal that is ignored (忽视) nowadays, it is breakfast.7．It was within easy walking distance (距离) of the hotel.8．I'm not a fashion victim; I stick to what suits (适合) me.9．You have to attach (把……附在……上) your photo to the application form.10．He was disabled in the war and his disability (残疾) prevented him from holding any job.Ⅱ.单句改错1．In Britain, sales of cigarettes have been reducing by 30% in the past ten years.reducing→reduced2．Working as volunteer in the local hospital made me much more sensitive to the needs of the disabled.as后加a3．He had changed so much that I could hardly know him.know→recognize4．The question is so puzzled that none of them can answer it correctly. puzzled→puzzling 5．Many people often ignore of the radiation that comes from TV or the computers.去掉of 6．Seeing from a distance, it looked like a human face.Seeing→Seen7．You'd better choose the activities which interest you and suit for you.去掉for8．She attached a stamp on the envelop.on→toⅢ.选词填空be related to， make the most of， rather than， in the distance， work out， leave out， be curious about， come across1．I will do it myself rather_than ask him to do it.2．We have worked_out the plan and now we must put it into practice.3．These children are_curious_about how the little elephants find food.4．Every minute should be made_the_most_of to study our lessons well.5．Not until recently did we realize that language was closely related_to culture.6．I could just see a car in_the_distance,_but I couldn't make out what color it was.7．Yesterday I came_across a foreign girl on the street, who looked worried.8．I was feeling left_out in the new school when Alice, an easygoing girl from Canada, came to stay with me.二、勤练高考题型，多练自能生巧Ⅰ.阅读理解Many blind people use guide dogs to help them get safely from place to place and to warn them of danger.But what can blind people do if they are allergic (过敏的) to dogs or just don't like them? For some people, the answer is provided by the Guide Horse Foundation.Janet and Don Burleson founded the organization in 1999.They began training miniature horses to help guide blind people.Miniature horses look just like regular horses, only much smaller.They are generally less than 34 inches tall.Cuddles was the foundation's first guide horse in full service.She became 45yearold Dan Shaw's helper.Shaw has an eye disease and his sight is very poor.One night, while filling out a form to get a guide dog, Shaw heard a news story on TV about people training horses to guide the blind.Shaw loves horses and wanted a guide animal that would live a long time, He applied (申请), and a year later, Cuddles and Shaw began training as a team.On a trip to New York, Cuddles helped Shaw safely tour Times Square, a very busy part of the city at night.The next day, Cuddles calmly rode the elevator with Shaw to the crowded top of the Empire State Building, a famous tall building.Cuddles even guided Shaw on the boat ride to the Statue of Liberty, and traveled on the subway system.Shaw says that he is very lucky to have Cuddles.He believes that Cuddles has changed his life for the better by giving him the chance to do things himself and making him feel much more confident about himself.语篇解读：本文是一篇说明文。
2021-2022学年人教版高中化学选修三课时跟踪检测(三) 原子结构与元素周期表 Word版含解析
课时跟踪检测（三）原子结构与元素周期表1．某元素简化电子排布式为[Xe]4f46s2，其应在()A．s区B．p区C．d区D．f区解析：选D元素在周期表中的分区，取决于元素原子的最终一个电子所进入的能级，因最终一个电子进入f能级，所以该元素为f区元素。
2．外围电子排布为3d104s2的元素在周期表中的位置是()A．第三周期ⅦB族B．第三周期ⅡB族C．第四周期ⅦB族D．第四周期ⅡB族解析：选D该元素的最大能层数为4，应位于第四周期，3d和4s电子数之和为12，应在第12列，是ⅡB族。
3．按电子排布，可把周期表里的元素划分成5个区，以下元素属于s区的是()A．Fe B．MgC．Al D．La解析：选B周期表在分区时，依据最终一个电子所进入的能级来分，若最终一个电子进入s轨道则为s区。
A项Fe的电子排布式为1s22s22p63s23p63d64s2，为d区；B项Mg的电子排布式为1s22s22p63s2，为s 区；C项Al的电子排布式为1s22s22p63s23p1，为p区；D项La为镧系元素，属于f区。
4．下列说法中，正确的是()A．s区都是金属元素B．s区都是主族元素C．稀有气体在ds区D．全部非金属元素都在p区解析：选B s区包括第ⅠA族和ⅡA族，第ⅠA族中含有氢元素，A项错误，B项正确；稀有气体属于p区元素，C项错误；氢元素在s区，故D项错误。
5．下列说法中错误的是()①全部的非金属元素都分布在p区②元素周期表中从ⅢB族到ⅡB族10个纵行的元素都是金属元素③除氦以外的稀有气体原子的最外层电子数都是8④同一元素的各种同位素的物理性质、化学性质均相同A．①②B．②③C．③④D．①④解析：选D非金属元素中氢在s区，其余非金属均分布在p区；同一元素的各种同位素的化学性质均相同，但物理性质不同。
6．若某基态原子的外围电子排布为4d15s2，则下列说法正确的是()A．该元素基态原子中共有3个电子B．该元素原子核外有5个电子层C．该元素原子最外层共有3个电子D．该元素原子M能层共有8个电子解析：选B该元素基态原子的电子排布式为1s22s22p63s23p63d104s24p64d15s2，原子中共有39个电子，有5个电子层，最外层有2个电子，M能层有18个电子。
高一化学同步人教版必修二课时跟踪检测：(三) 核 素 含答案
课时跟踪检测（三） 核 素1.136C 与14 7N 具有相同的( )A ．质量数B ．质子数C ．电子数D ．中子数解析：选D 13 6C的中子数为13－6＝7，14 7N 的中子数为14－7＝7，因此二者具有相同的中子数。
2．下列关于16 8O 的叙述正确的是( ) A ．质量数为8 B ．质子数为8 C ．中子数为16 D ．电子数为16解析：选B168O的质子数是8，中子数是8，质量数是16，电子数是8。
3．氢有三种同位素：11H 、21H 和31H ，它们之间存在的差异是( )A ．中子数B ．电子数C ．原子序数D ．质子数解析：选A 氢的三种同位素11H 、21H 和31H 之间存在的差异是中子数不同，质子数＝核外电子数＝原子序数。
4．下列属于同位素的一组是( ) A ．O 2、O 3B ．Na 2O 、Na 2O 2 C.4019K 、4020CaD ．H 、D 、T解析：选D A 项，O 2、O 3是氧的两种同素异形体，错误；B 项，Na 2O 、Na 2O 2属于不同物质，错误；C 项，4019K 、4020Ca 属于不同元素的核素，错误；D 项，H 、D 、T 互称同位素，正确。
5．下表符号中“2”的含义正确的一组是( )解析：选B 1222个氯原子，Ca 2＋中的2表示带2个电荷。
6．已知R 2＋离子核外有a 个电子，b 个中子。
表示R 原子符号正确的是( ) A.b a RB.a ＋b －2a －2R C.a ＋ba －2RD.a ＋b ＋2 a ＋2R解析：选D R2＋离子是原子失去2个电子形成的，原子核外有a＋2个电子，核内有b 个中子，a＋2个质子，表示R原子符号正确的是a＋b＋2R。
a＋27．碘有多种放射性同位素，如碘125、碘129和碘131等，下列说法中正确的是()A.125 53I和129 53I的质子数相同，互称为同位素B.129 53I和131 53I的中子数相同，互称为同位素C.125 53I和131 53I的核外电子数相同，是同一种核素D.125 53I、129 53I和131 53I的质量数不同，不能互称为同位素I、129 53I和131 53I的质子数均为53，但中子数不等(分别为72、76、78)，为解析：选A12553碘元素的三种不同核素，它们之间互称为同位素。
高中英语北师大版版必修3练习Unit 7 课时跟踪练(三) Lesson 2 & Lesson 3—Pre reading Word版含解
课时跟踪练(三) Lesson 2 & Lesson 3—Pre-readingⅠ.阅读理解AThere are eight species of dolphins in Hawaii. The bottle-nosed dolphin is the most common type of dolphin. This name came from its longer upper and lower jaws. This dolphin is a very loving and friendly animal. There are cases of dolphins that rescue injured divers in the ocean.In Hawaii, you can experience swimming with dolphins. There are several companies on Oahu and the Big Island that offer a swim with these animals in the wild. These kinds of tours usually are combined with water sports such as snorkel (水下呼吸管) or scuba diving.Dolphins are protected by the Marine Mammal Protection Act and it is against the law to become closer than 50 yards (45 m)to them. But these friendly animals can approach to check you out. You have to consider that if dolphins prefer to keep away, you should not try to swim close to them. If dolphins come close while you are swimming in the ocean, don't attempt to touch them and don't make aggressive or sudden movements.At the Sea Life Park on Oahu, they have special dolphin programs that allow you to swim and hug dolphins, besides, you'll learn about these mammals' habits. The Dolphin Quest program will explain to you why dolphins are considered one of the most intelligent creatures.Swimming with dolphins is one of the most attractive activities if you come to Hawaii. But Hawaii's underwater world is amazing and has many other species to watch：Humpback whales，Green sea turtles，Monk seals and so on.While you get in touch with this underworld，always have in mind the main rule of the ocean respect: Look but don't touch.语篇解读：本文向读者介绍在夏威夷和海豚一起游泳时需要注意的几点事项。
2022秋新教材高中数学课时跟踪检测三并集与交集新人教A版必修第一册
并集与交集层级(一) “四基”落实练1．已知集合A＝{x|－3≤x＜4}，B＝{x|－2≤x≤5}，则A∪B等于( )A．{x|－3≤x≤5} B．{x|－2≤x＜4}C．{x|－2≤x≤5} D．{x|－3≤x＜4}解析：选A 因为集合A＝{x|－3≤x＜4}，集合B＝{x|－2≤x≤5}，所以A∪B＝{x|－3≤x≤5}，故选A.2．已知集合M＝{0,1,2}，N＝{x|x＝2a－1，a∈N*}，则M∩N等于( )A．{0} B．{1,2}C．{1} D．{2}解析：选C 因为N＝{1,3,5，…}，M＝{0,1,2}，所以M∩N＝{1}．3．(2020·全国卷Ⅲ)已知集合A＝{1,2,3,5,7,11}，B＝{x|3<x<15}，则A∩B中元素的个数为( )A．2 B．3C．4 D．5解析：选B ∵A＝{1,2,3,5,7,11}，B＝{x|3<x<15}，∴A∩B＝{5,7,11}，A∩B中有3个元素，故选B.4．(多选)已知集合A＝{(x，y)|y＝x}，B＝{(x，y)|x2＋y2＝1}，则A∩B中的元素有( )A. B.C. D．－解析：选AB 由解得或∴A∩B＝.故选A、B.5．(2020·全国卷Ⅰ)设集合A＝{x|x2－4≤0}，B＝{x|2x＋a≤0}，且A∩B＝{x|－2≤x≤1}，则a＝( )A．－4 B．－2C．2 D．4解析：选B 法一：易知A＝{x|－2≤x≤2}，B＝，因为A∩B＝{x|－2≤x≤1}，所以－＝1，解得a＝－2.故选B.法二：由题意得A＝{x|－2≤x≤2}．若a＝－4，则B＝{x|x≤2}，所以A∩B＝{x|－2≤x≤2}，不满足题意，排除A；若a＝－2，则B＝{x|x≤1}，所以A∩B＝{x|－2≤x≤1}，满足题意；若a＝2，则B＝{x|x≤－1}，所以A∩B＝{x|－2≤x≤－1}，不满足题意，排除C；若a＝4，则B＝{x|x≤－2}，所以A∩B＝{x|x＝－2}，不满足题意，排除D.故选B.6．设集合A＝{1,2,3}，B＝{－1,0,2,3}，C＝{x∈R|－1≤x＜2}，则A∪B＝________，(A∪B)∩C＝________.解析：由题意得A∪B＝{－1,0,1,2,3}，∴(A∪B)∩C＝{－1,0，1,2,3}∩{x∈R|－1≤x＜2}＝{－1,0,1}．答案：{－1,0,1,2,3} {－1,0,1}7．已知集合A＝{1,2,3}，B＝{x|－1＜x＜2，x∈Z}，则集合A∪B中元素的个数是________．解析：∵B＝{x|－1＜x＜2，x∈Z}＝{0,1}，∴A∪B＝{0,1,2,3}，有4个元素．答案：48．已知集合A＝{x|2＜x＜4}，B＝{x|a＜x＜3a(a＞0)}．(1)若A∪B＝B，求a的取值范围；(2)若A∩B＝∅，求a的取值范围．解：(1)因为A∪B＝B，所以A⊆B，如图．观察数轴可知，a的取值范围为.(2)因为a＞0，所以B≠∅，则A∩B＝∅有两类情况：B在A的左边和B在A的右边，如图．观察数轴可知，a≥4或3a≤2，又a＞0，所以a的取值范围为.层级(二) 能力提升练1．设集合A＝{1,2}，B＝{1,2,3}，C＝{2,3,4}，则(A∩B)∪C等于( )A．{1,2,3} B．{1,2,4}C．{2,3,4} D．{1,2,3,4}解析：选D 因为A＝{1,2}，B＝{1,2,3}，所以A∩B＝{1,2}．又C＝{2,3,4}，所以(A∩B)∪C＝{1,2}∪{2,3,4}＝{1,2,3,4}．2．(多选)满足M⊆{a1，a2，a3，a4}，且M∩{a1，a2，a3}＝{a1，a2}的集合M可能是( )A．{a1，a2} B．{a1，a2，a3}C．{a1，a2，a4} D．{a1，a2，a3，a4}解析：选AC 由题意知集合M必含有元素a1，a2，并且不含元素a3，故M＝{a1，a2}或M＝{a1，a2，a4}．故选A、C.3．设A＝{x|2x2－px＋q＝0}，B＝{x|6x2＋(p＋2)x＋5＋q＝0}，若A∩B＝，则p ＋q＝________，A∪B＝________.解析：由题意可得∈A，∈B，∴解得∴p＋q＝－11.∴集合A＝{x|2x2＋7x－4＝0}＝，B＝{x|6x2－5x＋1＝0}＝，故A∪B＝.答案：－11 4．设集合A＝{2，－1，x2－x＋1}，B＝{2y，－4，x＋4}，C＝{－1,7}，且A∩B＝C，求x，y及A∪B.解：由已知A＝{2，－1，x2－x＋1}，B＝{2y，－4，x＋4}，C＝{－1,7}且A∩B＝C得7∈A,7∈B且－1∈B，所以在集合A中x2－x＋1＝7，解得x＝－2或3.当x＝－2时，在集合B中，x＋4＝2，又2∈A，故2∈A∩B＝C，但2∉C，故x＝－2不合题意，舍去．当x＝3时，在集合B中，x＋4＝7.故有2y＝－1，解得y＝－，经检验满足A∩B＝C.综上知，所求x＝3，y＝－.此时，A＝{2，－1,7}，B＝{－1，－4,7}．故A∪B＝{－4，－1,2,7}．5．已知集合A＝{x|x≥3}，B＝{x|1≤x≤7}，C＝{x|x≥a－1}．(1)求A∩B，A∪B；(2)若C∪A＝A，求实数a的取值范围．解：(1)因为A＝{x|x≥3}，B＝{x|1≤x≤7}，所以A∩B＝{x|3≤x≤7}，A∪B＝{x|x≥1}．(2)因为C∪A＝A，A＝{x|x≥3}，C＝{x|x≥a－1}，所以C⊆A，所以a－1≥3，即a≥4.故实数a的取值范围为{a|a≥4}．层级(三) 素养培优练1．现有100名携带药品出国的旅游者，其中75人带有感冒药，80人带有胃药，那么对既带感冒药又带胃药的人数统计中，下列说法正确的是( )A．最多人数是55 B．最少人数是55C．最少人数是75 D．最多人数是80解析：选B 设100名携带药品出国的旅游者组成集合I，其中带感冒药的人组成集合A，带胃药的人组成集合B.设所携带药品既非感冒药又非胃药的人数为x，则0≤x≤20.设以上两种药都带的人数为y.由图可知，x＋card(A)＋card(B)－y＝100.∴x＋75＋80－y＝100.∴y＝55＋x.∵0≤x≤20，∴55≤y≤75，故最少人数是55.2．已知A＝{x|x2－ax＋a2－19＝0}，B＝{x|x2－5x＋6＝0}，是否存在实数a使A∩B)？若存在，求出集合A，B同时满足下列三个条件：(1)A≠B；(2)A∪B＝B；(3)∅(a的值；若不存在，请说明理由．解：假设存在实数a使A，B满足条件，由题意得B＝{2,3}．∵A∪B＝B，∴A⊆B，即A＝B或A B.又A≠B，∴A B.又∅ (A∩B)，∴A≠∅，即A＝{2}或{3}．当A＝{2}时，将x＝2代入A中方程得a2－2a－15＝0.即a＝－3或a＝5.当a＝－3时，A＝{2，－5}，与A＝{2}矛盾，舍去；当a＝5时，A＝{2,3}，与A＝{2}矛盾，舍去．当A＝{3}时，将x＝3代入A中方程得a2－3a－10＝0，即a＝－2或a＝5.当a＝－2时，A＝{3，－5}，与A＝{3}矛盾，舍去；当a＝5时，A＝{2,3}，与A＝{3}矛盾，舍去．综上所述，不存在实数a使集合A，B满足条件．。
高中物理 课时跟踪训练(三)位置变化快慢的描述速(第1课时)高一物理试题
积盾市安家阳光实验学校课时跟踪训练(三) 位置变化快慢的描述—速度 (第1课时)A级—学考达标1．下列关于速度的说法正确的是( )A．京沪高速铁路上的列车最高时速可达484 km/h，指的是瞬时速度的大小B．沪宁高速公路限速120 km/h，指的是平均速度的大小C．子弹射出枪口时的速度为500 m/s，指的是平均速度的大小D．某运动员百米跑的成绩是10 s，则他冲刺时的速度大小一为10 m/s解析：选A 京沪高速铁路上的列车最高时速可达484 km/h，指的是瞬时速度的大小，选项A正确；沪宁高速公路限速120 km/h，指的是瞬时速度的大小，选项B错误；子弹射出枪口时的速度为500 m/s，指的是瞬时速度的大小，选项C错误；某运动员百米跑的成绩是10 s，则他的平均速度大小是10 m/s，但是冲刺时的速度大小不一为10 m/s，选项D错误。
2．以往公路上用单点测速仪测车速，个别司机由于熟知测速点的位置，在通过测速点前采取刹车降低车速来逃避处罚，但很容易造成追尾事故，所以有些地方已开始采用区间测速。
下列说法正确的是( )①单点测速测的是的瞬时速率②单点测速测的是的平均速率③区间测速测的是的瞬时速率④区间测速测的是的平均速率A．①③B．①④C．②③D．②④解析：选B 单点测速测的是在测速点那一位置的速率，是瞬时速率，①正确，②错误；区间测速测的是在一段路程内的平均速率，③错误，④正确。
3．以下关于瞬时速度、平均速度、平均速率的说法正确的是( )A．瞬时速度是指物体在某一位置或某一时刻的速度B．平均速度是物体在一段时间内各个时刻瞬时速度的平均值C．做变速运动的物体，平均速率就是平均速度的大小D．物体做变速运动时，平均速度是指物体通过的路程与所用时间的比值解析：选A 瞬时速度是指物体在某一位置或某一时刻的速度，选项A正确；平均速度是物体在某一段时间内的位移与经过这段位移所用时间的比值，并不是物体在某一段时间内各个时刻瞬时速度的平均值，平均速率是指物体通过的路程与所用时间的比值，一般情况下，运动物体的位移大小和路程是不相的，选项B、C、D错误。
高中英语北师大版必修1文档Unit 1 课时跟踪练(三) Lesson 2 & Lesson 3 Word版含答案
课时跟踪练(三) Lesson 2 & Lesson 3一、全练语言点，基稳才能楼高Ⅰ.单词拼写1．Studying abroad can be stressful (压力的), because you have to worry about adjusting to a new culture at the same time.2．My father promised me a car after my graduation (毕业)．3．Experts (专家们) point out that fruit juices can be harmful to children’s teeth.4．I must congratulate you on the excellent design (设计) of the new bridge.5．I’m tired of the endless advertisements (广告) on TV.6．During the summer holiday, college students are encouraged to take part in social (社会的) activities.7．The volunteers (志愿者们) made a suggestion to people present at the meeting that we should take some measures to protect wildlife.8．Also, to improve our English and get more students interested in English, I intend to organise (组织) some activities at school.9．These days, I can’t fall asleep because the coming final exam is putting great pressure (压力) on me.10．She needs a high income to support (供养) such a large family.Ⅱ.单句改错1．Nowadays many children prefer surfing the Internet at home to take exercise outdoors.take→taking2．Honestly speaking, I am not used to get up early.get→getting3．I can’t stand work with Jane in the same office. She just refuses to stop talking while she works.work→working4．When I got home, I found my brother played the piano.played→playing5．Mary is 5 kilos thinner than before. That’s to say, she reduced her weight to 5 kilos.第二个to→by6．All the people in the world hope to live a peacefully life.peacefully→peaceful 7．We won’t go out for a walk unless it rains.unless→if8．It is so challenged a job that I can’t finish it on my own.challenged→challenging Ⅲ.选词填空1．I’m on_a_diet and I only have some fruits for supper.2．In_support_of his sister, he sold his only house to pay the school fee.3．The old man thought I stepped on his foot by_design.4．Her health broke down under_the_stress_of work.5．As is known to us, the letters PLA stand_for the People’s Liberation Army.6．Schools must meet_the_challenge of new technology.7．It is likely that you will suffer_from bad health if you keep smoking.8．Everyone should pay_attention_to protecting his own eyesight.9．Great changes have_taken_place in the school over the past three years, which deeply impresses me.10．I used_to go to work by bike, but now I go to work by car.Ⅳ.串点成篇微表达根据最新的调查发现，很多夫妇宁愿 (prefer to) 只要一个小孩而不愿 (rather than) 再生一个。
2021-2022学年高中英语人教版必修3习题：Unit 1 课时跟踪练(三) Word版含答案
课时跟踪练(三) Learning about Language & Using Language一、全练语言点，基稳才能楼高[本课语言点针对练习]Ⅰ.单词拼写1．Obviously (明显), the students are not interested in the subject.2．My mother often reminds (提示) me to study hard.3．You can't take photographs here without permission (许可)．4．Mr. Jones sent his apologies (赔礼) for not attending the meeting.5．He was really brave enough to save the drowning (溺水的) boy from the rough sea.6．The boy fooled (哄骗) her into believing him.7．It was with great sadness (难过) that we learned of his death.8．They all forgave (原谅) him for the mistake he had made.9．She wept (流泪) bitter tears over her lost youth.10．I wiped (擦去) my shoes on the mat before I came in.Ⅱ.单句语法填空1．You must apologize to your parents for being so rude.2．Can you forgive me for giving you so much trouble?3．Mary, I reminded John of his promise to help you.4．The prison authorities permit visiting (visit) him only once a month.5．Benjamin Franklin set about learning (learn) the printer's trade at an early age.6．In a word, it is time for us to improve the safety of school buses.7．It is obvious to everybody that the only way to achieve one's goal is to work hard.8．Living (live) miles away, he attended the course.9．She couldn't make herself heard (hear) because of the traffic noise.10．Jack had something more important to do; as a result, he couldn't turn up this evening.Ⅲ.选词填空turn up, turn on, set off, throw away, remind sb. of ..., keep one's word, hold one's breath, drown one's sadness in alcohol1．I expect the missing watch will turn_up one day.2．He held_his_breath,_not daring to make any sound.3．I believe whatever he says, for he always keeps_his_word.4．I set_off for the company earlier in order to avoid the heavy traffic.5．On arriving home, he turned_on the TV and began to watch the sports news.6．Don't throw_away the rubbish. It can be recycled. 7．After his wife died, the man often drowned_his_sadness_in_alcohol.8．They sing and dance happily, which reminds_me_of my experience.[本单元语言点温故练习]Ⅰ.单句语法填空1．Only by keeping ourselves healthy and strong can we feel energetic (energy)．2．After walking the whole day, I was almost out of breath (breathe), not feeling bad, though. 3．Don't sit there doing (do) nothing.4．I owe you an apology (apologize) for what I said this morning.5．Obviously (obvious), the ship set out on its voyage without permission last night. 6．No one can truly understand my sadness (sad)．7．She is looking at me as though/if she knew (know) me.8．Festivals are meant (mean) to celebrate important events of the year.9．We didn't permit taking (take) books out of the library.10．Jack set out at seven in the morning; he should be here now.11．If you must go, at least wait until the storm is over.12．Great changes have_taken (take) place in my hometown since two years ago.Ⅱ.补全句子1．The stone pavilion is in_memory_of_a_famous_poet.这石亭是为了纪念一位有名的诗人。
2021-2022学年高中语文苏教版必修三课时跟踪检测(三) 咬文嚼字 Word版含答案
课时跟踪检测（三）咬文嚼字一、语言表达专练1．依次填入下列各句中横线处的词语，最恰当的一项是( )①在当前困难局面下，企业要秉持集腋成裘、________的“小家子气”，坚决摒弃只看金山不见碎银的“大款气”，用深化挖潜汇成的涓涓细流滋养企业渡过难关。
②作为中国女子网球的标志性人物，她极具共性的言行，甚至有些________、睚眦必报的处事风格，在肯定程度上，有失一个世界级体育名人的风度。
③《三国演义》里的周瑜是个________的人，他因嫉妒诸葛亮的聪慧才智而被活活气死，然而历史上的周瑜却并非如此，史书上说他“性度恢廓”“实奇才也”。
A．小肚鸡肠斤斤计较锱铢必较B．锱铢必较斤斤计较小肚鸡肠C．斤斤计较小肚鸡肠锱铢必较D．锱铢必较小肚鸡肠斤斤计较解析：选B 锱铢必较：对很少的钱或很小的事都要计较，原形容办事格外认真，一丝不苟，现多形容过于吝啬或气量小。
斤斤计较：形容过分计较微小的利益或无关紧要的事情。
前者多用于钱财，后者指在细小的事物上也要计较，适用范围广泛得多。
小肚鸡肠：形容气量狭小，只计较小事，不顾大局。
由①句中的“小家子气”“大款气”等，可知①句强调企业在当前应对很少的钱都要计较，故①句中应填“锱铢必较”。
由②句中的“睚眦必报的处事风格”，可知②句强调“她”过分计较微小的利益或无关紧要的事情，故②句中应填“斤斤计较”。
由③句中的“他因嫉妒诸葛亮的聪慧才智而被活活气死”，可知③句强调周瑜气量小，故③句中应填“小肚鸡肠”。
2．下列各句中，没有语病的一项是( )A．但是在文学，无论阅读和写作，我们必需有一字不愿放松的谨严。
B．熟路引诱性最大，人们对它的抵制力最低，一人走过，人人就都跟着走，没有一点新颖的意味，愈走就愈平滑俗滥。
C．我期望读者从这粗枝大叶的争辩中，可以领会运用文字所应有的谨严精神。
D．通过学习《咬文嚼字》，使我明白了语言和思想情感相随而变的道理。
解析：选C A项关联词使用不当，“和”应改为“或”；B项语序不当，应为“愈走就愈平滑俗滥，没有一点新颖的意味”；D项无主语，去掉“通过”或“使”。
2023新教材高中物理课时跟踪检测三电场电场强度粤教版必修第三册
课时跟踪检测（三） 电场 电场强度A 组—重基础·体现综合1．(2021·福州八校联考)关于电场强度的概念，下列说法正确的是( ) A ．由E ＝Fq可知，某电场的电场强度E 与q 成反比，与F 成正比 B ．电场中某一点的电场强度与放入该点的试探电荷的正负无关C ．正、负试探电荷在电场中同一点受到的电场力方向相反，所以某一点电场强度方向与放入试探电荷的正负有关D ．电场中某一点不放试探电荷时，该点电场强度等于零解析：选B E ＝F q是电场强度的定义式，某电场的电场强度E 的大小和方向都取决于电场本身，而与试探电荷的电荷量q 、试探电荷受到的电场力F 无关，故A 、C 错误，B 正确；某点不放试探电荷时，该点的电场依然存在，故D 错误。
2．下列关于电场线的说法中正确的是( )A ．电场线是从正电荷(或无穷远)出发到无穷远(或负电荷)终止的不封闭曲线B ．电场线上任何一点的切线方向总是与置于该点的点电荷的受力方向一致C ．沿着电场线方向电场强度逐渐减小D ．沿着电场线方向电场强度逐渐增大解析：选A 根据电场线定义可知，电场线是从正电荷(或无穷远)出发到无穷远(或负电荷)终止的不封闭曲线，故A 正确； 电场线上任何一点的切线方向是电场强度方向，总是与置于该点的正点电荷的受力方向一致，与负点电荷受力方向相反，故B 错误；电场线的疏密代表电场强度的大小，与电场线方向无关，故C 、D 错误。
3.(2021·中山检测)如图所示是点电荷Q 周围的电场线，图中A 到Q 的距离小于B 到Q 的距离。
以下判断正确的是( )A ．Q 是正电荷，A 点的电场强度大于B 点的电场强度 B ．Q 是正电荷，A 点的电场强度小于B 点的电场强度C ．Q 是负电荷，A 点的电场强度大于B 点的电场强度D ．Q 是负电荷，A 点的电场强度小于B 点的电场强度解析：选A 正电荷的电场线向外辐射，电场线密的地方电场强度大，所以A 正确。
高中英语人教版高二选修6课时跟踪检测(三) 含解析
课时跟踪检测(三)Warming Up & Reading — Language PointsI .单句语法填空1.At that time, I found it hard to convev (convey) my feeling in words.2.It' s too bad of you lo tcasc (tease) the child like that.3.He climbed up the tree and hid among the branches (branch).4.The prince wayjransformed (transform) into a frog in the fairy tale.5.I don' t understand, so please give me a more concretc (concrete) example than this one.6.The reason wh、，I don, t know how to comniunicate with her is that we have seldom sat down and exchanged our feelings and thoughts.7.With a vital exam drawing (draw) near, I felt so nervous that I even couldn' t eat or sleep.8.Half of the girls choose film and TV stars as their idols, while 48% of the boys favour sports stars.9.As the weather is getting drier and drier, the farmers are running (run) out of the water in the pool.10.To achieve one' s dream, one must try to equip oneself with rich knowledge and set a goal easy to reach (reach).n.完成句子nguage is one of the significant means for mankind to conveY」hou2hts and feclings.对人类来说，语言是传递思想和感情的一种重要方式。
高考物理总复习课时跟踪检测(三) 自由落体和竖直上抛运动
课时跟踪检测（三）自由落体和竖直上抛运动1．如图所示是用照相机对一小球做自由落体运动频闪拍摄的照片，符合实际的是( )解析：选D 自由落体运动是匀加速直线运动，因此照片中相邻小球间的距离会逐渐增大，故D正确。
2．(多选)有一直升机停在200 m高的空中静止不动，有一乘客从窗口由静止每隔1 s释放一个钢球，则钢球在空中的排列情况下列说法正确的是( )A．相邻钢球间距离相等B．越靠近地面，相邻钢球间的距离越大C．早释放的钢球落地时的速度大D．在落地前同一时刻，早释放的钢球速度总是比晚释放的钢球速度大解析：选BD 初速度为零的匀加速直线运动，在连续相等的时间间隔内，位移之比为1∶3∶5∶…，故越靠近地面，相邻球间的距离越大，故A错误，B正确；根据位移时间关系公式，有v2＝2gh，解得：v＝2gh，故钢球落地速度都相等，故C错误；在落地前，早释放的钢球加速运动时间长，故速度大，故D正确。
3．某同学在墙前连续拍照时，恰好有一小石子从墙前的某高处由静止落下，拍摄到石子下落过程中的一张照片如图所示。
由于石子的运动，它在照片上留下了一条模糊的径迹。
已知毎层砖的平均厚度为 6.0 cm，这个照相机的曝光时间为2.0×10－2 s ，则( )A ．石子下落到A 位置时的速度约为60 m/sB ．石子下落到A 位置时的速度约为12 m/sC ．石子下落到A 位置所需的时间约为0.6 sD ．石子下落到A 位置所需的时间约为1.2 s解析：选C 由题图可以看出，在曝光的时间内，石子下降了大约有两层砖的厚度，即12 cm(0.12 m)，曝光时间为2.0×10－2 s ，所以AB 段的平均速度为：v ＝0.122×10－2 m/s ＝6 m/s ；由于时间极短，故A 点的速度近似为6 m/s ，由v ＝gt 可得下降的时间为：t ＝v g ＝610 s ＝0.6 s ，故C项正确，A 、B 、D 三项错误。
2021-2022学年高中英语人教版必修3习题：Unit 2 课时跟踪练(三) Word版含答案
课时跟踪练(三) Learning about Language & Using Language一、全练语言点，基稳才能楼高[本课语言点针对练习]Ⅰ.单词拼写1．They didn't fight, but stood there glaring (怒视) at each other.2．In my opinion，keeping dogs should not be banned，but limited (限制) to certain areas.3．Wang Peng began to advertise the benefits (好处) of his food.4．He consulted (查阅) his notebook repeatedly during his speech.5．“I wish I didn't have so much to do.” she sighed (叹息)．6．Have you digested (理解) everything that is important in the book?7．He spied (窥探) a man hiding in some bushes.8．They combined (联合) to form a new government.Ⅱ.单句语法填空1．It is not polite to spy on what girls are wearing.2．He is so stubborn that no one can persuade him.3．Neither the father nor the son is (be) interested in the film.4．There is no doubt that the plants benefited from the rain.5．In order to save energy, they have decided to cut down the gas supplies to the city.6．As a writer, he combines wisdom with passion.7．David, I'm tired of watching television; let's go for a walk.8．The mother was trembling with anger.She glared at her son and said nothing.9．The speed of cars and trucks is limited to 30 kilometers per hour in large cities in China.10．The experts consulted with each other about how to reduce the loss caused by the earthquake.11．They didn't go to the park yesterday. Neither/Nor did we.12．Eating healthy will prevent you putting on weight.Ⅲ.选词填空glare at，spy on，earn one's living，in debt，put on weight，cut down，be of great benefit，before long1.He earns_his_living by doing all kinds of things.2．The book is_of_great_benefit to you.3．Don't get him to lend you any money any more, because he himself is in_debt.4．Many big trees along the road have been cut_down for building houses.5．He has put_on_weight after recovery.6．The woman glared_at the young man coldly, which made him embarrassed.7．Before_long he began to realize how serious mistakes he had made. 8．John admitted that he had followed Ms. Evans and spied_on her.[本单元语言点温故练习]Ⅰ.单句语法填填空1．I need to pay off all my debts before I leave the village.2．You can't get away with lying (lie) every time!3．I had my watch stolen (steal) last week.4．Before long, our family moved and had to give the pet away.5．She had a feeling that she was being watched, that is, spied on.6．This is so expensive a camera that I can't afford it.7．He has cut down his expenses to pay for his schooling.8．I bought the coat at a discount of 60%.9．She asked the question out of curiosity (curious)．10．Don't always eat the same kind of food, because we should have a balanced (balance) diet. Ⅱ.补全句子1．This article is too long, so you have to cut_it_down_to_1,000_words.这篇文章太长了，因此，你得把它压缩到一千字才行。
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课时跟踪训练(三)[要点对点练]一、简谐运动的回复力1．关于简谐运动的回复力，下列说法正确的是()A．可以是恒力B．可以是方向不变而大小变化的力C．可以是大小不变而方向改变的力D．一定是变力[解析]简谐运动的回复力与质点离开平衡位置的位移大小成正比，方向始终指向平衡位置，故F是变力，故D对．[答案] D2．对简谐运动的回复力公式F＝－kx的理解，正确的是() A．k只表示弹簧的劲度系数B．式中的负号表示回复力总是负值C．位移x是相对平衡位置的位移D．回复力只随位移变化，不随时间变化[解析]位移x是相对平衡位置的位移；F＝－kx中的负号表示回复力总是与振动物体的位移方向相反，故C正确．[答案] C3．一弹簧振子在一条直线上做简谐运动，第一次先后经过M、N两点时速度v(v≠0)相同，那么，下列说法正确的是() A．振子在M、N两点受回复力相同B．振子在M、N两点对平衡位置的位移相同C．振子在M、N两点加速度大小相等D．从M点到N点，振子先做匀加速运动，后做匀减速运动[解析]弹簧振子做简谐运动，先后经过M、N两点时速度v(v≠0)相同，根据对称性可知M、N两点关于平衡位置对称，两点相对于平衡位置的位移大小相等、方向相反，根据F＝－kx可知，回复力大小相等、方向相反，说明回复力相反，故A、B错误；M、N两点相分析可知加速度大小相对于平衡位置的位移大小相等，根据a＝－kxm等，故C正确；从M点到N点，回复力先减小后增大，振子的加速度先减小后增大，所以振子先做变加速运动，后做变减速运动，故D 错误．[答案] C4．对于弹簧振子的回复力与位移的关系图象，下列图象中正确的是()[解析]根据公式F＝－kx，可判断回复力与位移的关系图象是一条直线，斜率为负值，故C正确．[答案] C5．有一个在y轴方向上做简谐运动的物体，其振动曲线如图1所示．关于图2的判断正确的是()A．图甲可作为该物体的速度—时间(v－t)图象B．图乙可作为该物体的回复力—时间(F－t)图象C．图丙可作为该物体的回复力—时间(F－t)图象D．图丁可作为该物体的加速度—时间(a－t)图象[解析]位移为零时速度最大，A错误；回复力与位移关系为F，a－t图象应与F－t图象一＝－kx，B错误，C正确；加速度a＝Fm致，D错误．[答案] C6．一质点做简谐运动，其位移x与时间t的关系曲线如图所示，由图可知()A．质点振动频率是4 HzB．t＝2 s时，质点的加速度最大C．t＝2 s时，质点的振幅为－2 cm D．t＝3 s时，质点所受的合外力最大[解析]由图读出周期T＝4 s，则频率f＝1T＝0.25 Hz，故A错误；t＝2 s时，质点的位移最大，则由a＝－kxm知加速度最大，故B正确；由图读出振幅为2 cm，C错误；t＝3 s时，质点位于平衡位置，位移x＝0，则由a＝－kxm知加速度为零，则回复力为零，故D错误．[答案] B二、简谐运动的能量7．做简谐运动的物体(包括做弧线运动的单摆)每次通过平衡位置时()A．位移为零，动能为零B．动能最大，势能最小C．速率最大，回复力不一定为零D．速率最大，合力一定为零[答案] B8．(多选)把一个小球套在光滑细杆上，球与轻弹簧相连组成弹簧振子，小球沿杆在水平方向做简谐运动，它围绕平衡位置O在A、B间振动，如图所示，下列结论正确的是()A．小球在O位置时，动能最大，加速度最小B．小球在A、B位置时，动能最小，加速度最大C．小球从A经O到B的过程中，回复力一直做正功D．小球从B到O的过程中，动能增大，势能减小，总能量不变[解析]小球在平衡位置O时，弹簧处于原长，弹性势能为零，动能最大，位移为零，加速度为零，A项正确；在最大位移A、B处，动能为零，加速度最大，B项正确；由A→O，回复力做正功，由O→B，回复力做负功，C项错误；由B→O，动能增加，弹性势能减少，总能量不变，D项正确．[答案]ABD9．(多选)装有一定量液体的玻璃管竖直漂浮在水中，水面足够大，如图甲所示．把玻璃管向下缓慢按压4 cm 后放手，忽略运动阻力，玻璃管的运动可以视为竖直方向的简谐运动，测得振动周期为0.5 s ．竖直向上为正方向，某时刻开始计时，其振动图象如图乙所示，其中A 为振幅．对于玻璃管，下列说法正确的是( )A ．回复力等于重力和浮力的合力B ．振动过程中动能和重力势能相互转化，玻璃管的机械能守恒C ．位移满足函数式x ＝4sin ⎝⎛⎭⎪⎫4πt －5π6 cm D ．振动频率与按压的深度有关E ．在t 1～t 2时间内，位移减小，加速度减小，速度增大[解析] 装有一定量液体的玻璃管只受到重力和液体的浮力，所以装有一定量液体的玻璃管做简谐振动的回复力等于重力和浮力的合力，故A 正确；玻璃管在做简谐振动的过程中，液体的浮力对玻璃管做功，所以振动的过程中玻璃管的机械能不守恒，故B 错误；振动的周期为0.5 s ，则圆频率ω＝2πT ＝2π0.5＝4πrad/s ，由图可知振动的振幅为A ，由题可知，A ＝4 cm ，t ＝0时刻：x 0＝－12A ＝A sin φ0，结合t ＝0时刻玻璃管振动的方向向下，可知φ0＝76π⎝ ⎛⎭⎪⎫116π舍去，则玻璃管的振动方程为：x ＝A sin(ωt ＋φ0)＝4sin ⎝ ⎛⎭⎪⎫4πt ＋76π cm ＝4sin ⎝ ⎛⎭⎪⎫4πt －56π cm ，故C 正确；由于玻璃管做简谐振动，与弹簧振子的振动相似，结合简谐振动的特点可知，该振动的周期与振幅无关，故D 错误；由图可知，在t 1～t 2时间内，位移减小，回复力：f ＝－kx ，加速度a ＝f m ＝－kx m 减小；在t 1～t 2时间内，玻璃管向着平衡位置做加速运动，所以速度增大，故E 正确．[答案] ACE[综合提升练]10．(多选)在简谐运动中，振子每次经过同一位置时，下列各组中描述振动的物理量总是相同的是( )A ．速度、加速度、动能B ．速度、动能、回复力C ．加速度、动能和位移D ．位移、动能和回复力[解析] 振子每次过同一位置时，位移相同，由F ＝－kx 和a ＝－k m x 知，回复力和加速度相同，速度大小相同，但方向不一定相同，动能相同，故A 、B 错，C 、D 正确．[答案] CD11．某弹簧振子在水平方向上做简谐运动，其位移x 随时间t 变化的关系为x ＝A sin ωt ，振动图象如图所示，下列说法不正确的是( )A ．弹簧在第1 s 末与第3 s 末的长度相同B ．简谐运动的角速度ω＝π4rad/s C ．第3 s 末振子的位移大小为22A D ．从第3 s 末到第5 s 末，振子的速度方向发生变化[解析] 由图可知T ＝8 s ，ω＝2πT ＝π4rad/s ，故t ＝1 s 与第3 s 末，x ＝22A ，A 对，B 对，C 对．在2 s ～5 s 内速度方向不变，故D 错．[答案] D12．(多选)如图所示，物体A 置于物体B 上，一轻质弹簧一端固定，另一端与B 相连，在弹性限度范围内，A 和B 一起在光滑水平面上做往复运动(不计空气阻力)，并保持相对静止．则下列说法正确的是()A．A和B均做简谐运动B．作用在A上的静摩擦力大小与弹簧的形变量成正比C．B对A的静摩擦力对A做功，而A对B的静摩擦力对B不做功D．B对A的静摩擦力始终对A做正功，而A对B的静摩擦力始终对B做负功[解析]在弹性限度内，AB整体受到弹簧的拉力大小为：F＝kx，方向与位移方向相反，所以A和B都做简谐运动，选项A正确；物体A受到的静摩擦力提供物体A做简谐运动的回复力，大小为：f＝k′x，选项B正确；从平衡位置向最大位移运动的过程中，B对A 的静摩擦力对A做负功，A对B的静摩擦力对B做正功，从最大位移向平衡位置运动的过程中，B对A的静摩擦力对A做正功，A对B 的静摩擦力对B做负功，选项C、D错误．[答案]AB13．如图为某个弹簧振子做简谐运动的图象，由图象可知()A．由于在0.1 s末振幅为零，所以振子的振动能量为零B．在0.2 s末振子具有最大势能C．在0.4 s末振子具有的能量尚未达到最大值D．在0.4 s末振子的动能最大[解析]简谐运动的能量是守恒的，故A、C错；0.2 s末、0.4 s 末位移最大，动能为零，势能最大，故B对，D错．[答案] B14．两块质量分别为m1，m2的木板，被一根劲度系数为k的轻弹簧连在一起，并在m1板上加压力F，如图所示．为了使得撤去F 后，m1跳起时恰好能带起m2板，则所加压力F的最小值为()A．m1gB．2m1gC．(m1＋m2)gD．2(m1＋m2)g[解析]加力F平衡时，F＋m1g＝kA，撤去力F瞬间kA－m1g ＝m1a，m1跳起时，恰好带起m2板，则对m1有m2g＋m1g＝m1a，联立得F＝(m1＋m2)g，选项C正确．[答案] C15．一个弹簧振子在A、B间做简谐运动，如图(甲)所示，O是平衡位置，以某时刻作为计时零点(t＝0)经过14周期，振子具有正方向的最大加速度，那么图(乙)中的四个x－t图象能正确反映运动情况的是()[解析] 由F ＝－kx 和a ＝F m ，得a ＝－kx m ，在经过T 4后，a >0且最大，故此时x 为负的最大值，故选D.[答案] D16．(多选)如图所示，物体m 系在两弹簧之间，弹簧劲度系数分别为k 1和k 2，且k 1＝k ，k 2＝2k ，两弹簧均处于自然状态，今向右拉动m ，然后释放，物体在B 、C 间振动，O 为平衡位置(不计阻力)，则下列判断正确的是( )A ．m 做简谐运动，OC ＝OBB．m做简谐运动，OC≠OBC．回复力F＝－kxD．回复力F＝－3kx[解析]m在平衡位置O处两弹簧均处于原长状态，则m振动后任取一位置A，如图．设在A处m的位移为x，则在A处m所在水平方向的合力F＝k2x＋k1x＝(k2＋k1)x，考虑到回复力F与x方向关系有：F＝－(k2＋k1)x＝－3kx，选项D正确，C错误；可见m做的是简谐运动，由简谐运动的对称性可得OC＝OB，选项A正确，B错误．[答案]AD17．如图，一轻弹簧一端固定，另一端连接一物块构成弹簧振子，该物块是由a、b两个小物块粘在一起组成的．物块在光滑水平面上左右振动，振幅为A0.当物块向右通过平衡位置时，a、b之间的粘胶脱开；以后小物块a振动的振幅为A，则A________A0(填“>”、“<”或“＝”)．[解析]当弹簧振子通过平衡位置时，a、b之间粘胶脱开，a、b 由于惯性继续向右运动，弹簧伸长，对物块有向左的拉力，物块a向右做减速运动，动能减少，物块b在光滑水平面上做匀速直线运动，动能不变，由能量守恒定律知只有物块a减少的动能转化为弹簧的弹性势能，所以弹簧的最大伸长量减小，故振幅减小．[答案]<18．一质量为m，侧面积为S的正方体木块，放在水面上静止(平衡)，如图所示．现用力向下将其压入水中一段深度后(未全部浸没)撤掉外力，木块在水面上下振动，试判断木块的振动是否为简谐运动．[解析]以木块为研究对象，设静止时木块浸入水中Δx深，当木块又被压入水中x后所受力如图所示，则F回＝mg－F浮，①又F浮＝ρgS(Δx＋x)．②由①式和②式，得F回＝mg－ρgS(Δx＋x)＝mg－ρgSΔx－ρgSx.mg＝ρgSΔx，所以F回＝－ρgSx.即F回＝－kx(k＝ρgS)．所以木块的振动为简谐运动．[答案]木块的振动是简谐运动。