限时训练(1)
限时训练1
高三物理限时训练一班别_______________ 姓名_________________ 座号____________________ 1. 下列关于速度的说法正确的是： ( )A ．速度是描述物体位置变化的物理量B ．速度方向就是物体运动的方向C ．位移方向和速度方向一定相同D ．平均速度的大小就是平均速率2．某人爬山，从山脚爬上山顶，然后又从原路返回到山脚，上山的平均速率为v 1，下山的平均速率为v 2，则往返的平均速度的大小和平均速率是( )A.v 1＋v 22， v 1＋v 22B.v 1－v 22， v 1－v 22C ．0，v 1－v 2v 1＋v 2 D ．0， 2v 1v 2v 1＋v 23．一艘船以恒定的速率，往返于上、下游两码头之间．如果以时间t 1和t 2分别表示水的流速较小和较大时船往返一次所需的时间，那么，两时间的长短关系为( )A ．t 1＝t 2B ．t 1>t 2C ．t 1<t 2D ．条件不足，不能判断4．下表是四种交通工具的速度改变情况，下列说法正确的是( )A.C ．③的速度变化最快 D ．④的末速度最大，但加速度最小 5.一个质点做运动方向不变的直线运动，加速度的方向始终与速度方向相同，但加速度的大小逐渐减小直至为零，在此过程中( )A.速度逐渐减小，当加速度减小到零时，速度达到最小B.速度逐渐增大，当加速度减小到零时，速度达到最大C.位移逐渐增大，当加速度减小到零时，位移将不再增加D.位移逐渐减小，当减速度减小到零时，位移达到最小6．一物体做匀变速直线运动，初速度为15 m/s ，方向向东，第5 s 末的速度为10m/s ，方向向西，则第几秒开始物体向西运动（ ）A ．第2sB ．第4sC ．第9sD ．第15s7． 2008年9月25日晚21点10分，我国在九泉卫星发射中心将我国自行研制的“神舟7号”宇宙飞船成功地送上太空，飞船绕地球飞行一圈时间为90分钟．则( )A ．“21点10分”和“90分钟”前者表示“时刻”后者表示“时间”B ．卫星绕地球飞行一圈，它的位移和路程都为零C ．卫星绕地球飞行一圈平均速度为零，但它在每一时刻的瞬时速度都不为零D ．地面卫星控制中心在对飞船进行飞行姿态调整时可以将飞船看作质点8.一质点做匀加速直线运动，第三秒内的位移2m，第四秒内的位移是2.5m，以下说法中正确的是（）A．这两秒内平均速度是2.25m/s B．第三秒末即时速度是2.50m/sC．质点的加速度是0.125m/s2 D．质点的加速度是0.5m/s29. 一辆汽车从原点O由静止出发沿x轴做直线运动，为研究汽车的运动而记下它的各时刻(1)(3)汽车在第4秒内的平均速度为多大？10．一辆汽车沿平直公路从甲站开往乙站，起动加速度为2m/s2，加速行驶5秒，后匀速行驶2分钟，然后刹车，滑行50m，正好到达乙站，求汽车从甲站到乙站的平均速度？解析：(1)v 2＝3m/s (2)a ＝Δv ＝4－23－1m/s 2＝1m/s 2(3)Δx 4＝3.5m ，t ＝1s ，v 4＝Δx 4t 4＝3.5m/s.解析：起动阶段行驶位移为： s 1=2121at ……（1） 匀速行驶的速度为： v = at 1 ……（2） 匀速行驶的位移为： s 2 =vt 2 ……（3） 刹车段的时间为： s 3 =32t v……（4） 汽车从甲站到乙站的平均速度为：v =s m s m s m t t t s s s /44.9/1351275/10120550120025321321==++++=++++。
2020高考英语江苏专用版考前冲刺5周限时练辑：限时训练(一) Word版含解析
限时训练(一)Ⅰ.单项填空1.Without the wise leadership of the Party，it hard to achieve the GDP growth target for 2022.A.would have beenB.would beC.wereD.had been答案 B解析考查虚拟语气。
句意为：要是没有党的英明领导，很难实现2022年国内生产总值增长的目标。
此处without短语相当于虚拟条件句，根据题干中的“2022”判断是对将来的虚拟，主句用would＋do的形式，故B项正确。
2.Parents’top priority is to help their kids develop the ability to show in their choices of friends.binationB.admirationC.inspirationD.discrimination答案 D解析考查名词词义辨析。
combination结合；admiration钦佩；inspiration灵感；discrimination 区别，识别。
句意为：父母的首要任务是帮助他们的孩子发展在选择朋友时的识别能力。
根据句意可知D项正确。
3.As Emerson puts it，we travel the world over to find the beautiful，we must carry it with us or we find it not.A.unlessB.untilC.thoughD.because答案 C解析考查连词词义辨析。
句意为：如爱默生所言，我们环游世界是为了寻找美，但是我们必须与美同行才能发现它。
unless除非；until直到；though尽管；because因为。
根据句意可知，这里表示一种让步关系，故选C。
4.I felt like giving up.I probably ，but my Dad whispered，“Come on! You can make it.”A.would haveB.wouldC.shouldD.should have答案 A解析考查过去将来时。
地理限时训练(一)【建议时间15分钟】
地理限时训练（一）【建议时间15分钟】
使用日期：选题：张毅老师批阅人：得分：姓名： 1.
读“地质构造示意图”，完成下列问题。
（14分）
（1）从地质构造上看属于向斜的字母是，属于地堑的字母是。
（2）出现图中“背斜成谷，向斜成山”这一地形倒置现象是受到（内力/外力）作用；
关于这一现象叙述正确的是。
（双选）
①向斜槽部受挤压力的作用岩层坚实不易侵蚀形成的山地
②背斜槽部受挤压力的作用岩层坚实不易侵蚀形成的谷地
③向斜顶部受张力的作用岩层脆弱受外力侵蚀形成的山地
④背斜顶部受张力的作用岩层脆弱受外力侵蚀形成的谷地
（3）若开采地下水，最好在处；若为开采方便，采石场最好选择处（填字母）。
2.读六大板块示意图，完成下列问题。
（16分）
（1）图中表示美洲板块的是（序号）；⑥表示的板块名称是（名称）；
（2）日本群岛是_____板块（序号）和_____板块（序号）（张裂/挤压）形成的，其位于板块的______（生长/消亡）边界附近，地壳较为活跃，故其多、等地质灾害。
注：本次测验选自于2014年重庆一中高2017级高一上期第三次定时练习（2014.12）背诵要点收获：
地理限时训练（一）【参考答案】
1.
2.(每空2分，共16分)
(1) ______⑤__ ____，南极洲板块。
(2) _______①______，_____②________，_____挤压______，
_____消亡__ ___，_____火山______，_____地震______
（注：第2小题：1和2、5和6答题顺序可互换）。
2021届江苏省常州市金沙高级中学高三下学期限时训练(一)英语试题(解析版)
江苏省常州市金沙高级中学2021届高三下学期限时训练（一）英语试题第一部分：阅读理解（共两节，满分30分）第一节（共7个小题：每小题2.5分，满分17.5分）AWhat do the random, scribbled(潦草的)drawings crowding the margins(页边空白)of most high school students’ papers mean? When a student is caught doodling(乱画)in class, he will probably be criticized for daydreaming. But doodling while listening can help with remembering details, rather than implying that the mind is wandering, according to a study published in the scientific journal Applied Cognitive Psychology.In an experiment conducted by the Medical Research Council’s Cognition and Brain Sciences Unit in Cambridge,40 subjects were asked to listen to a two-minute tape giving several names of people and places. Half of the participants were asked to shade in shapes on a piece of paper at the same time, without paying attention to neatness, while the rest were given no such instructions. After the tape had finished, all participants in the study were asked to recall the names of people and places. The doodlers recalled on average 7.5 names of people and places, compared to only 5.8 by the non-doodlers.“If someone is doing a boring task, like listening to a dull telephone conversation, they may start to daydream.” said study researcher, Professor Jackie Andrade, of the School of P sychology, University of Plymouth. “Daydreaming distracts them from the task, resulting in poorer performance. A simple task, like doodling, may be enough to stop daydreaming without affecting performance on the main task.”“In psychology, tests of memory or attention will often use a second task to selectively block a particular mental process. If that process is important for the main task, then performance will be weakened. But my research suggests that in everyday life doodling may be something we do because it helps to keep us on track with a boring task, rather than being an unnecessary distraction(分心)that we should try to resist doing.” said Andrade.Dan Ware, a social study teacher, used to consider doodling a distraction from learning, butafter teaching kids with all personality types he learned scribbling away during lectures helps certain students remember more information. “In my first few years of teaching, I thought, ‘Well, this kid isn’t paying attention. He’s daydreaming.’ But I had some real ly powerful experiences with students and came to understand in many cases that was their way of focusing, and those students were probably paying more attention than other students.” Ware said.1. What do we know about the participants involved in the experiment?A. Some were asked to note down the information neatly.B. Some were asked to memorize the names they would hear.C. Some were instructed to listen to the tape with full attention.D. Some were instructed to make random drawings on paper.2. Which of the following will both Jackie Andrade and Dan Ware agree with?A. Doodling helps some people focus.B. Doodling makes a dull task interesting.C. Students who doodle perform poorly.D. Students who doodle lack concentration.3. What is the best title of the text?A. Daydreaming Can Sharpen Study SkillsB. Doodling Can Help Memory RecallC. A Wandering Mind Improves ProductivityD. Distractions Harm Academic PerformanceBShyness is the cause of much unhappiness for a great many people. Shy people are anxious and self-conscious; that is, they are concerned about their own appearance and actions too much. Negative thoughts are constantly occurring in their minds: What kind of impression am I making? Do they like me? Do I sound stupid? Am I wearing unattractive clothes?It is obvious that such uncomfortable feelings must affect people unfavorably. A person’s self-concept is reflected in the way he or she behaves and the way a person behaves affects other people’s reactions. In general, the way p eople think about themselves has a deep effect on all areas of their lives.Shy people, who have low respect, are likely to be passive and easily influenced by others. They need faith that they are doing ＂the right thing＂. Shy people are very sensitive to criticism. It makes them feel inferior(自卑). They also find it difficult to be pleased by praises because they believe they are unworthy of praise. A shy person may respond to a praise with a statement like this one: ＂You’re just saying that to make me feel good. I know it’s not true.＂It is clear that,. while self-awareness is a healthy quality, overdoing it is harmful.Can shyness be completely got rid of, or at least reduced? Fortunately, people can overcomeshyness with determination since shyness goes hand in hand with lack of self-respect. It isimportant for people to accept their weaknesses as well as their strengths. Each one of us has hisor her own characteristics. We are interested in our own personal ways. The better we understandourselves, the easier it becomes to live up to our chances for a rich and successful life.4. The first paragraph is mainly about ____________.A. the cause of shynessB. the effect of shyness on peopleC. the feelings of shy peopleD. the questions in the minds of shy people5. According to the writer, self-awareness is ____________.A. harmful to peopleB. a weak point of peopleC. the cause of unhappinessD. a good characteristic6. What is the shy people’s reaction to praise?A. They are pleased by it. B They feel it is not true.C. They are very sensitive to it.D. They feel they are worthy of it.7. We can learn from the passage that shyness ____________.A. blocks our chances for a successful lifeB. helps us to live up to our full developmentC. enables us to understand ourselves betterD. has nothing to do with lack of self-respect第二节（共5小题，每小题2.5分，满分12.5分）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选项。
高三英语晚自习限时训练 (1)
高三英语晚自习限时训练【3月31日晚限制：不超过65-70分钟】一、六选四阅读1. Complete the following passage by using the sentences given below. Each sentences can be used only once. Note that there are two more sentences than you need.Can just one person make a difference? You bet! In a community every person counts, and getting involved is not difficult. Take stock of your own talents and interests. Don't wait for someone else to act first. Take the initiative! Once you see what you can accomplish, you'll want to keep going.Here are just a few ways to make a difference in your community. How many more ways can you come up with?Clean up the community. People often throw litter in places where there is already litter. And the problem only becomes worse until someone gets fed up and does something. Could your neighborhood use a cleanup? Neighborhood cleanups are often sponsored by local businesses or schools. But if your community doesn't have a cleanup program, get together with friends to organize one. You could pick up garbage in a larger area twice a year, or you could clean a smaller area every few months.Include the isolated. Do you know anyone who is housebound? Almost all neighborhoods have a few people who have to stay at their homes. These people are often elderly and unable to leave their homes to perform simple tasks. By letting them "borrow" your legs and eyes, you can make them feel included. You can run errands for them like shopping or paying bills. They might like you to read to them if their eyesight is failing. Governments provide some of the services these people need, but programs cannot give them friendship; that's what communities are for!Reading clubs are popular all over Europe and North America. Members might read at home to prepare for discussion, or they might read aloud to each other and talk about what they just read. Either way, a book or article can spark lively discussion and this often challenges people to take action.A. Cleaning your community will have a positive effect on others in society.B. They find a need or an issue you really care about.C. But they belong to the community, too.D. Living in a clean neighborhood will be its own reward.E. Don't hesitate to take part in the community's activity.F. Round up some readers.二、语法填空阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。
限时训练1
高二物理（创）周考练一、选择题（1、4、10、11、12多选，其他单选）1．下列说法中正确的是()．A．每种金属都有确定的电阻率，电阻率不随温度变化B．导线越细越长，其电阻率也越大C．一般金属的电阻率，都随温度升高而增大D．测电阻率时，为了提高精度，通过导线的电流要足够大，而且要等到稳定一段时间后才可读数2.电位器是变阻器的一种．如图所示，如果把电位器与灯泡串联起来，利用它改变灯的亮度，下列说法正确的是()．A．连接A、B使滑动触头顺时针转动，灯泡变暗B．连接A、C使滑动触头逆时针转动，灯泡变亮C．连接A、C使滑动触头顺时针转动，灯泡变暗D．连接B、C使滑动触头顺时针转动，灯泡变亮3．如图所示是电阻R1和R2的伏安特性曲线，并且把第一象限分为Ⅰ、Ⅱ、Ⅲ三个区域，现在把R1和R2并联在电路中，消耗的电功率分别为P1和P2，并联总电阻设为R.下列关于P1和P2的大小关系及R的伏安特性曲线应该在的区域正确的是()．A．特性曲线在Ⅰ区，P1<P2B．特性曲线在Ⅲ区，P1>P2C．特性曲线在Ⅰ区，P1>P2D．特性曲线在Ⅲ区，P1<P24．某导体中的电流随其两端电压的变化如图7-1-9所示，则下列说法中正确的是()．A．加5 V电压时，导体的电阻约是5 ΩB．加12 V电压时，导体的电阻约是1.4 ΩC．由图可知，随着电压的增大，导体的电阻不断减小D．由图可知，随着电压的减小，导体的电阻不断减小5．两个电阻，R1＝8 Ω，R2＝2 Ω，并联在电路中，欲使这两个电阻消耗的电功率相等，可行的办法是()．A．用一个阻值为2 Ω的电阻与R2串联B．用一个阻值为1 Ω的电阻与R2串联C．用一个阻值为6 Ω的电阻与R1串联D．用一个阻值为2 Ω的电阻与R1串联6.甲、乙两根保险丝均为同种材料制成，直径分别是d1＝0.5 mm和d2＝1 mm，熔断电流分别为2.0 A和6.0 A，把以上两根保险丝各取等长一段并联后再接入电路中，允许通过的最大电流是().A.6.0 A B．7.5 AC.10.0 A D．8.0 A7．如图所示，电源电动势E＝8 V，内电阻为r＝0.5 Ω，“3 V，3 W”的灯泡L与电动机M串联接在电源上，灯泡刚好正常发光，电动机刚好正常工作，电动机的线圈电阻R0＝1.5 Ω.下列说法中正确的是()．A．通过电动机的电流为1.6 AB．电源的输出功率是8 WC．电动机消耗的电功率为3 WD．电动机的输出功率为3 W8．两根材料相同的均匀导线x和y串联在电路中，两导线沿长度方向的电势变化情况分别如图中的ab段和bc段图线所示，则导线x和y的横截面积之比为()．A．2∶1 B．1∶2C．6∶1 D．1∶69．在如图所示的电路中，E为电源，其内阻为r，L为小灯泡(其灯丝电阻可视为不变)，R1、R2为定值电阻，R3为光敏电阻，其阻值大小随所受照射光强度的增大而减小，V为理想电压表．若将照射R3的光的强度减弱，则()．A．电压表的示数变大B．小灯泡消耗的功率变小C．通过R2的电流变小D．电源内阻消耗的电压变大10．如图所示，电源电动势为E，内阻为r，不计电压表和电流表内阻对电路的影响，当电键闭合后，两小灯泡均能发光．在将滑动变阻器的触片逐渐向右滑动的过程中，下列说法正确的是()．A．小灯泡L1、L2均变暗B．小灯泡L1变亮，小灯泡L2变暗C．电流表A的读数变小，电压表V的读数变大D．电流表A的读数变大，电压表V的读数变小11．如图所示，电源电动势为E，内电阻为r，两电表均可看做是理想电表．闭合开关，使滑动变阻器的滑片由右端向左滑动，在此过程中()．A．小灯泡L1、L2均变暗B．小灯泡L1变暗，L2变亮C．电流表A的读数变小，电压表V的读数变大D．电流表A的读数变大，电压表V的读数变小12、如图所示电路中，电源内阻不能忽略，两个电压表均为理想电表．当滑动变阻器R 2的滑动触头P 滑动时，关于两个电压表V 1与V 2的示数，下列判断正确的是( )．A ．P 向a 滑动V 1示数增大、V 2的示数减小B ．P 向b 滑动V 1示数增大、V 2的示数减小C ．P 向a 滑动，V 1示数改变量的绝对值小于V 2示数改变时的绝对值D ．P 向b 滑动，V 1示数改变量的绝对值大于V 2示数改变量的绝对值二、解答题13．两个分别用长l = 5cm 的绝缘细线悬挂于同一点的相同金属小球（可视为点电荷），带有等量同种电荷。
高三英语晚自习限时训练 (1)
高三英语限时训练一、阅读理解A7-Day Tour from London to EdinburghA London guide will show you the city’s famous landmarks like Buckingham Palace, Downing Street and Westminster Abbey. Then, in Edinburgh, you’ll tour the castle and see Scotland’s Crown Jewels. From the historical sights to the beautiful scenery, this guided tour of England and Scotland is a great way to experience everything Britain has to offer.Starting at: $849 per person9-Day Tour from Dublin to LondonYour guided tour of Ireland and Britain begins in the capital cityof Dublin. Enjoy seeing the “Fair City”, including the statue-lined O’Connell Street, Trinity College, and St. Patrick’s Cathedral. Your local guide will show you the famous sights, including the Houses of Parliament, Big Ben, Westminster Abbey and Buckingham Palace. This guided tour of Ireland and Britain is a welcome escape with fewer crowds and lower costs than high-season tours.Starting at: $1069 per person7-Day Tour from London to ParisYour guided vacation in London begins with a welcome dinner and a cruise on the Thames River to admire the Tower Bridge and the Houses of Parliament. You’ll spend three nights in London to see the sites ofthis historic city—from Big Ben to Buckingham Palace, and also St. Paul’s Cathedral. Then you’ll enjoy a 3-night stay in Paris. This includes sightseeing at the Arc de Triomphe, Concorde Square, Champs-Elysees, and a Seine cruise. This guided tour of London and Paris is certain to be enjoyable with fewer crowds in the off-season!Starting at: $1149 per person1. How much would a couple pay for the 7-day tour from London to Edinburgh?A．$849. B．$1149. C．$1698. D．$2138.2. Which place can you visit if you take the 9-day tour from Dublin to London?A．Downing Street. B．Trinity College. C．The Thames River. D．Concorde Square.3. What do the three tours have in common?A．They are all guided tours for visitors.B．People will spend the same amount of time.C．They all begin in the capital city of London.D．People can enjoy the same number of sights.BRace walking shares many fitness benefits with running, research shows, while most likely contributing to fewer injuries. It does, however, have its own problem.Race walkers are conditioned athletes. The longest track and field event at the Summer Olympics is the 50-kilometer race walk, which is about five miles longer than the marathon. But the sport’s rulesrequire that a race walker’s knees stay straight through most of theleg swing and one foot remain in contact (接触) with the ground at all times. It’s this strange form that makes race walking such anattractive activity, however, says Jaclyn Norberg, an assistantprofessor of exercise science at Salem State University in Salem, Mass.Like running, race walking is physically demanding, she says, According to most calculations, race walkers moving at a pace of six miles per hour would burn about 800 calories(卡路里) per hour, which is approximately twice as many as they would burn walking, although fewer than running, which would probably burn about 1,000 or more calories per hour.However, race walking does not pound the body as much as running does, Dr. Norberg says. According to her research, runners hit the ground with as much as four times their body weight per step, while race walkers, who do not leave the ground, create only about 1.4 times their body weight with each step.As a result, she says, some of the injuries associated with running, such as runner’s knee, are uncommon amo ng race walkers. But thesport’s strange form does place considerable stress on the ankles and hips, so people with a history of such injuries might want to becautious in adopting the sport. In fact, anyone wishing to try race walking should probably first consult a coach or experienced racer to learn proper technique, she says. It takes some practice.4. Why are race walkers conditioned athletes?A．They must run long distances.B．They are qualified for the marathon.C．They have to follow special rules.D．They are good at swinging their legs.5. What advantage does race walking have over running?A．It’s more popular at the Olympics.B．It’s less challenging physically.C．It’s more effective in body building.D．It’s less likely to cause knee injuries.6. What is Dr. Norberg’s suggestion for someone trying race walking? A．Getting experts’ opinions.B．Having a medical checkup.C．Hiring an experienced coach.D．Doing regular exercises.7. Which word best describes the author’s attitude to race walking? A．Skeptical. B．Objective.C．Tolerant. D．Conservative.CAn unconventional method for growing rice has been found to increase yields(产量) by 20 to 50 percent. Reports from China, India, Southeast Asia and Africa suggest that average yield increases of 20 to 50 percent are regularly being achieved by farmers adopting the "system of rice intensification(集约化)"(SRI)，which needs one-tenth as many seeds and aims to stimulate the root system of plants rather than trying to increase yields in the conventional way by using improved seeds and fertilizers.The idea of using less to gain more is seen as an important innovation(革新) for adapting farming to climate change and a way to increase yields at a time when human populations are growing fast but traditional plant breeding and genetically modified techniques have failed to increase yields more than a few percentage points, says Norman Uphoff, professor of international agriculture at Cornell.The new way to grow rice needs only half as much water, and is proving most popular in water-stressed countries, says Tavseef Mairaj Shah, a Ph.D．researcher. "Rice growing in Kashmir largely depends on irrigation systems that draw water from the river Jhelum. But climate change is leading to drier winters, untimely rains, and warmer summers."“SRI is a great technique, not just from the water-savingperspective but because it offers better yields and soil conditions. Different studies, both at the experimental level and farmer-participative level, have shown that SRl improves yields with less water.” Shah adds.Some academic, the global seed industry and the international community once rejected reports of “fantastic” yields, accusingfarmers of falsifying(篡改）records and researchers of carelessness and "non-science". But more than 600 articles, checked by SRI Internationalat Cornell University, have shown benefits.Uphoff says, “Attitudes are changing.The original hostility(敌意)has gone." However, the early opposition has resulted in comparativelylittle scientific research being conducted into SRI and a slow understanding by funders.8. How does SRI increase the yields of rice?A．By sowing more seeds B．By using improved seeds.C．By improving its root system. D．By adopting special fertilizers. 9. Compared with the conventional method for growing rice, SRI.A．needs less water B．increases labor costsC．requires better soil conditions D．depends on genetically modified techniques10. What was the global seed industry's initial attitude toward reportson SRI?A．Curious B．Skeptical. C．Approving D．Uninterested. 11. Which of the following can be the best title of the passage?A．How to Increase YieldsB．People's Attitudes Towards SRIC．An Innovative Means of Growing RiceD．The Disadvantages of Conventional Plant Breeding二、完形填空A Florida man likes to shop at garage sales for old plaques(纪念匾)so he can reuse the wooden backs. Recently, he was looking through a 12 he bought years ago when one 13 a small ball caught hiseye.The man took a moment to 14 what was written on the plaque and quickly realized there was a 15 stone inside the ball-a piece ofmoon rock brought back on the Apollo 17 mission in 1972. The plaque and rock had been a 16 to the state of Louisiana by then-President Richard Nixon but 17 ended up in a garage sale for the man to find years later.“I can’t even tell you how long I 18 i t for. I’m not evensure how much I 19 for it. The wood in the plaques is such nicewood and that is what I 20 them for," the man said. The man 21 t he Louisiana governor’s office, which 22 him to the LouisianaState Museum. The man hand-delivered his 23 to the Louisiana State Museum. He didn’t want to take a chance that something might happen toit during 24 .The museum’s director is 25 for hisgenerosity and 26 for reuniting the state with this priceless object. “It is an extraordinary piece of Louisiana history,” he said. “We’re 27 to take possession of this piece and to share it withour audiences.”After Apollo 17 28 on Earth, Nixon 29 379 pieces of the satellite stone to all the states as well as foreign nations. Over time, those gifts began to 30 A 2002 search found that many were unaccounted for. To date, the fate(命运)of 171 rocks remains 3112. A．painting B．ball C．book D．collection13. A．linking B．featuring C．sharing D．obtaining14. A．read B．stress C．think D．remember15. A．normal B．new C．precious D．similar16. A．gift B．signal C．threat D．change17. A．sometimes B．somehow C．instead D．never18. A．borrowed B．returned C．owned D．lost19. A．paid B．earned C．saved D．charged20. A．carry B．prepare C．push D．buy21. A．passed B．contacted C．recognized D．trusted22. A．attracted B．added C．pointed D．reported23. A．work B．find C．receipt D．letter24. A．delivery B．discovery C．construction D．treatment25. A．eager B．responsible C．famous D．grateful26. A．reason B．demand C．concern D．claim27. A．likely B．free C．embarrassed D．excited28. A．landed B．existed C．wandered D．failed29. A．threw away B．put aside C．turned in D．handed out30. A．improve B．disappear C．drop D．matter31. A．unforgettable B．unacceptable C．unknownD．undoubted三、七选五阅读I love learning foreign languages so much that I learn a new language every two years. When people find I’m a polyglot(通晓多种语言的人)，they always ask me,“How do you do that?” Honestly, my answerwill be, “I don’t know. I simply love learning languages.” 32 They want to know why they spend years learning even one language, never achieving fluency, and what’s the secret of being polyglots.33 And what do we have in common? I decided to find that out. I went to several events where language lovers gather to practice their languages, asked dozens of polyglots about methods they use, and heard dozens of approaches. Everybody seems to have a unique way to speak several languages fluently.34 All these polyglots talked about language learning as if it was great fun. They found ways to turn language learning from aboring subject into a pleasant daily activity. You should have seentheir faces when they were showing me their colorful grammar charts and handmade flash cards. 35 The methods are various, but they make sure it’s something enjoyable.I realized it’s actually how I learn. 36 Then interesting programs became my choice. So all is clear. If you don’t like writing words down on paper, type them in an app. If you’re a shy perso n, apply self-talk at home. This is how polyglots learn languages, and the best news is that it’s available to anyone willing to take the learning into their own hands.A．How can those with little talent be fluent?B．But people are never happy with the reply.C．There’s no shortcut to learning languages for anyone.D．One of them even made recipes in a foreign language.E．That made me wonder, too, how other polyglots actually do it. F．When learning Spanish last year, I was bored with textbooks. G．Polyglots simply found ways to enjoy the language-learning process.四、语法填空阅读下面短文, 在空白处填人1个适当的单词或括号内单词的正确形式.May 21st this year marks the first International Tea Day, which37 (name) by the United Nations on November 27th, 2019. To celebrate38 festival, a number of events took place at the ChineseBusinessman Museum in Beijing on Thursday.The chairman of the China Culture Promotion Society addressed the opening ceremony.“As a main promoter of the International Tea Day,the birthplace of tea and the 39 (large) tea-producing country, China has a 40 (responsible) to work with other countries to promote the healthy development of the tea industry. It can help tobuild a community with a shared future 41 mankind,” he said.Th e “First International Tea Day Tea Road Cooperative Initiative” issued (发布) at the ceremony calls for people working in the teaindustry to come together to promote (促进） international cooperation 42 cultural exchanges. A four-year tea promotion-Tea RoadCooperative Plan-was also issued in accordance with the initiative.___42___ (strengthen) the connection with young people, the event included a number of public promotional activities on social media,___43___( invite ) twenty-nine tea professionals from around the worldto have thirty-six hours of uninterrupted live broadcasts.The Chinese Ancient Tea Museum was 43 (official) unveiled(揭幕) at the ceremony, opening 44 (it) first exhibition: The Avenue of Truth - A Special Exhibition o f Pu’er Tea.五、应用文写作47. 假定你是李华，你校将举办以“English Literature Reading”为主题的英语原阅读活动，请你用英语为本次活动写一则宣传稿，内容包括：(1)活动目的；(2)活动安排；(3)发出号召。
选择题限时训练(一)
Ｒ 甲 是 乙 的 必 要 非 充 分 条 件
①ｆ上 ： ／ ｍ ＝／ 》 【 ｍ
②
ｍ上Ｊ Ｂ
＝ ｍ
Ｃ 甲是 乙的充要 条件
／ ｎ
Ｄ ．甲既不是 乙 的充 分条件 ， 不是 乙的必要 条件 也
上
（ ） 已 知 定 义 在 复 数 集 Ｃ 的 函 数 满 足ｆ ） 文 上 ＝
Ｉ慨 ＥＲ） １ ，
③
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ｏ Ｌ ｆ
Ｒ） ，
Ａ ０ Ｂ．ｉ
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Ｃ．１ Ｄ．２
④｛Ｏ ＝ｍ／ ｎ ， ￣ ／ｎ ８ 【
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１２ ， Ｒｔ则Ａ 等于（ ）２ ＋ ∈ ， ０ ）
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潜在 问题 ： 干知 识 中的 重 要 考 点 主
掌握 不 牢．如 第３ 的 茎叶 图 ， 同 题 有 学会 犯 一种 “ 当然 ” 想 的错 误 ． 能 不
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历史经典题限时训练(一)
历史经典题限时训练（一）（90分钟）注意事项：1.本试卷分为第Ⅰ卷（选择题）和第Ⅱ卷（非选择题）两部分。
答卷前，考生务必将自己的姓名、准考证号填写在答题卡上。
2.回答第Ⅰ卷时，选出每小题答案后，用铅笔把答题卡上对应题目的答案标号涂黑。
如需改动，用橡皮擦干净后，再选涂其他答案标号。
写在本试卷上无效。
3.回答第Ⅱ卷时，将答案写在题卡上。
写在本试卷上无效。
4.考试结束后，将本试卷和答题卡一并交回。
第Ⅰ卷本卷共36小题，每小题1.5分，共54分。
在每小题给出的四个选项中，只有一项是符合题目要求的。
1．商代甲骨卜辞中，有大量“受禾”“求年”“有足雨”的内容。
这反映了当时A．农业生产已是重要的经济活动B．农业的收成与祭祀活动密切相关C．巫师是农业生产的重要组织者D．自然环境恶化影响农业生产2．周代分封制下，各封国贵族按“周礼”行事，学说统一的“雅言”，促进了各地文化的整合。
周代的“雅言”最早应起源于现在的A．河南B．河北C．陕西D．山东3．在周代分封制下，墓葬有严格的等级规定。
考古显示，战国时期，秦国地区君王墓葬规模宏大，其余墓葬无明显等级差别；在经济发达的东方六国地区，君王、卿大夫、士的墓葬等级差别明显。
这表明A．经济发展是分封制度得以维系的关键B．分封制中的等级规定凸显了君主集权C．秦国率先消除分封体制走向集权统治D．东方六国仍严格遵循西周的分封制度4．有先秦思想家认为，“君上之于民也，有难则用其死，安平则尽其力”。
据此可知这位思想家强调A．君主无为而治B．强化血缘等级C．推行礼乐仁政D．实行严刑峻法5．孔子是儒家学派创始人，汉代崇尚儒学，尊《尚书》等五部书为经典，记录孔子言论的《论语》却不在“五经”之中。
对此合理的解释是A．“五经”为阐发孔子儒学思想而作B．汉代儒学背离了孔子的儒学思想C．儒学思想植根于久远的历史传统D．儒学传统由于秦始皇焚书而断绝6．柳宗元在《封建论》中评价秦始皇废封建、行郡县说：“其为制，公之大者也……公天下之端自秦始。
高一英语40分钟限时训练(1)(有答案)
高一英语限时训练1完形填空When Pat Jones finished college，she decided to travel around the world and see as many foreign places as she could __1__ she was young.Pat wanted to visit Latin America __2__，so she got a job __3__ an English teacher in a school in Bolivia.Pat spoke a little Spanish，__4__ she was able to communicate with her students even when they didn’t __5__ much English.A sentence she had read somewhere stuck in her mind；if you dream __6__ a foreign language，you have really mastered(掌握)it.Pat repeated this sentence to her students and __7__ that some day she would dream in Spanish and they would dream in __8__.One day，one of her __9__ students came up and explained in Spanish that he had not done his homework.He had __10__ early and had slept __11__.“What does this have to do with your __12__？”Pat asked.“I dreamed all night，Miss Jones.And my dream was in English.”“In English？”Pat was very __13__，since he was such a bad student.She was __14__ secretly jealous(嫉妒的)．Her __15__ was still not in Spanish.But she encouraged(鼓励)her young student.“Well，__16__me about your dream.”“All the people in the dream __17__ English.”the student said.“And all the signs were in English.All the newspapers and magazines and all the TV programs were in English.”“But that’s __18__，”said Pat.“What did all the people say to you？”“I’m sorry，Miss Jones.That’s __19__ I slept so badly.I didn’t __20__ a word they said.It was a nightmare(噩梦)！”1．A.because B．while C．if D．since2．A.first B．at first C．last D．at last3．A.for B．of C．as D．like4．A.and B．but C．so D．yet5．A.say B．know C．read D．write6．A.in B．about C．of D．for7．A.thought B．realized C．hoped D．wanted8．A.English B．Spanish C．Russian D．German9．A.bright B．excellent C．best D．worst10．A.got up B．gone to bed C．fallen asleep D．woken up11．A.well B．soundly C．badly D．heavily12．A.English B．language C．dream D．homework13．A.surprised B．worried C．pleased D．excited14．A.yet B．seldom C．also D．still15．A.study B．class C．word D．dream16．A.answer B．write C．tell D．ask17．A.read B．liked C．spoke D．learned18．A.wonderful B．terrible C．funny D．strange19．A.how B．why C．when D．because20．A.hear B．understand C．know D．remember阅读理解A篇In order to know a foreign language thoroughly(完全地)，four things are necessary.First，we must understand the language when we hear it spoken.Second，we must be able to speak it ourselves，correctly with confidence(自信)and without hesitation(犹豫)．Third，we must be able to make sentences that are correct in grammar.There is no short way to succeed in language learning .A good memory(记忆)is a great help，but is not enough only to memorize the rules from a grammar book.It is no much use learning by heart long lists(一览表)of words and their meanings，studying the dictionary and so on.We must learn by using the language.If we are pleased with a few rules we have memorized，we are not really learning the language.We must“learn through use”．Practice is important.We must practise speaking and writing the language whenever(无论何时)we can.21. The most important things to learn a foreign language are ______.A．understanding and speakingB．hearing，speaking，reading and writingC．writing and understandingD．memorizing and listening22. Someone hears and writes English very well，but he speaks it very badly.This isbecause________.A．he doesn’t understand the language when he hears it spokenB．he doesn’t have a good memoryC．he always remembers lists of words and their meaningsD．he often hesitates to practise speaking it23. Which of the following is the most important in learning a foreign language?A．A good memory. B．Speaking. C．Practice. D．Writing.24. “learn through use”means ______.A．we use a language in order to learn itB．we learn a foreign language in order to use itC．we can learn a language well while we are using itD．both B and CB篇A student is learning to speak British English.He wonders(想知道)：Can I communicate(交际)with Americans? Can they understand me? Learners of English often ask：What are the differences between British and American English? How important are these differences?Certainly，there are some differences between British and American English.There are a few differences in grammar.For example，speakers of British English say“in hospital”and“Have you a pen?”；Americans say “in the hospital”and“Do you have a pen?”．Pronunciation is sometimes different.Americans usually sound “r”s in words like“bird”and“hurt”．Speakers of British English do not sound “r”in these words.There are differences between British and American English in spelling and vocabulary. For example，“colour”and“honour”are British；“color”and“honor”are American.These differences in grammar，pronunciation，spelling and vocabulary are not important，however. For the most part，British and American English are the same language.25. American English and British English are different in ________.A．spelling B．pronunciation C．grammar D．all of the above26. What is NOT mentioned in the passage?A．Whether there are differences between British English and American English.B. Whether British English and American English are one language or two.C. How the differences between British English and American English cameabout.D．How important the differences are.27．Most ______ say，“Do you have a watch？”A．British people B．Americans C．children D．teachers 28．According to this passage，British people and Americans have ________ difficulty in understanding each other.A．little B．much C．some D．great语法填空Changes in Means of Transportation in Beijing.There have been many changes in the means of transportation in Beijing in recent years. From 1996 1._______ 2000,the number of the bicycles has2.________ (increase) by 40%, for it is convenient3._______ a good form of exercise to ride a bicycle. Over 18,000 taxis have appeared in 2000. More and more people like to take4.______(taxi) because they can save a lot of time and the price is5._________(reason). The number of private cars is 51000,6.________ is three times as much as that in 1996. We can see more and more people are7._______(get) rich and can afford to buy cars of8._______(they) own. The number of buses9.______(do) not change much. Though it is cheap to take buses, they are slow, dirty and crowded. Something must be done to improve 10.________ conditions of buses.短文改错Last night when Jim was getting over his lessons, his Grandma came into her room and chatted with him for a while. Then she got up from the sofa and wanted go to her bedroom. And suddenly she fell down to the ground. Jim was very frightened. Knew her heart trouble must have come again, he quickly phoned the nearest hospitals for help. Before the doctors came, he helped his grandma lay on her back and comfort her, which made her feel better. Soon help came in and his grandma was sent to hospital at once. One doctor said Jim had done the right thing and actual saved her life.高一英语限时1答题纸完形填空1-5 ____________________ 6-10____________________11-15____________________ 16-20____________________阅读理解21-24____________________ 25-28____________________语法填空1.___________2.__________3.__________4.__________5.__________6.__________7.__________8.__________9.__________10.__________短文改错Last night when Jim was getting over his lessons, his Grandma came into her room and chatted with him for a while. Then she got up from the sofa and wanted go to her bedroom. And suddenly she fell down to the ground. Jim was very frightened. Knew her heart trouble must have come again, he quickly phoned the nearest hospitals for help. Before the doctors came, he helped his grandma lay on her back and comfort her, which made her feel better. Soon help came in and his grandma was sent to hospital at once. One doctor said Jim had done the right thing and actual saved her life.高一英语限时1答案完型填空BACCB ACADB CDACD CCABB阅读理解BDCC DCBA语法填空 1.to 2.increased 3.and 4. taxis 5. reasonable 6.which 7.getting 8.their 9.does 10.the短文改错getting---going 2. her---his 3. wanted后加to 4.And---But 5. knew--knowing 6.hospitals---hospital y---lie fort---comforted 9.in删去10. actual---actually。
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h2
第 13 题图
14．（10 分）某中学科技小组的学生在进行电磁发射装置的课题研究，模型简化如下。在水平地面
上固定着相距为 L的足够长粗糙导轨 P Q 及 MN ，空间存在着可以调节的匀强磁场，方向竖直向
r 上，如图所示，导轨左侧末端接有电动势为 E 、内阻为 的电源，开关 K 控制电路通断。质量
图甲
2B 测量
HB 测量
图乙
第 12 题图
（2）经正确操作，小明选择多用电表欧姆档 “1”Ω，分别测 HB 和 2B 铅笔芯的电阻，指针位
置如图乙所示，则 RHB= ▲ Ω。初步得出结论：铅笔芯的石墨含量越大，电阻率 ▲ （填 “大”或者“小”）。
春晖中学高二年级（3 月）限时训练（一） 第 4页（共 6 页）
恰好与磁场圆的右端点相切，上极板与圆的最高点等高，两极板加上 U=6.24× 104V 的直流电压。
在圆形磁场的最低点 A 处有一放射源，它在 A 点切线上方 180°竖直平面内向上打出粒子射入圆
形磁场中，打出的粒子速率均相等，且按角度均匀分布，所有粒子经磁场偏转后，都能垂直电场
的方向进入电场中。已知，粒子的质量 m=9.6×10-27kg，电量 q=1.6×10-19C。假设到达下极板的粒
B．只要 d<0.8L，小球向右摆动的过程中都能到达与 A 点等高处 C．当 d=0.9L 时，小球向右摆动的过程中能够到达与 A 点等高处
春晖中学高二年级（3 月）限时训练（一） 第 1页（共 6 页）
第 4 题图
D．只要 d>0.92L，小球向右摆动的过程中都能到达与 A 点等高处
5．如图所示，在固定的斜面上 A、B、C、D 四点 ，AB=BC=CD。
D．运动员完成全程所需的总时间为 3s
3．2020年，我国将一次实现火星的“环绕、着陆、巡视”三个目标。假设探测器到达火星附近时，
先在高度恰好等于火星半径的轨道上环绕火星做匀速圆周运动，测得运动周期为T，之后通过变轨、
减速落向火星。探测器与火星表面碰撞后，以速度v竖直向上反弹，经过时间t再次落回火星表面。
右传播，P、Q 两质点位于波源 S 的两侧，且 P、Q 和 S
第 9 题图
的平衡位置在一条直线上，P、Q 的平衡位置到 S 的平衡
位置之间的距离分别为 14.6m、13.4m．已知波源振动的频率为 20Hz，波速为 16m/s，当 P、Q
开始振动后，下列判断正确的是
A. P、Q 两质点运动的方向始终相同
三个相同的小球分别从 A、B、C 三点以 v1、v2、v3 的水平速度抛出， v1
A
不计空气阻力，它们同时落在斜面的 D 点，则下列判断正确的是 A．A 球最后才抛出。 B．C 球的初速度最大。 C．A 球离斜面最远距离是 C 球的三倍。 D．三个小球落在斜面上速度方向与斜面成 300 斜向右下方。
三、计算题 13.（15 分）炎炎夏日，水上娱乐成为人们避暑消夏的首选，某水上游乐设施可简化为如图所示的 结构，MN 为高处平台，左侧为螺旋形光滑滑道，每圈高度落差不大，最后一圈为同一水平面上的 圆形滑道，半径 R=7.2m，螺旋滑道末端 E 与倾斜直滑道 EF 相连，MN 与 E 高度差为 h1=7.2m， EF 高度差为 h2=4.05m，右侧 PQ 为一与水平滑道，分别连接两段倾斜光滑直滑道，经过各点时不 计能量损耗，g=10m/s2, （1）一儿童质量 m=30kg，从左侧螺旋轨道顶端由静止 滑下，儿童到达螺旋滑道末端 E 点时的速度大小； （2）（1）中的儿童经过螺旋滑道末端 E 点时，儿童对滑 道的作用力大小； （3）有人为寻求刺激，从右侧滑道由静止滑下时，直接 由 Q 点水平飞出落入水中，若 PQ 的高度可调，求 PQ 距水面多高时，落水位置到 Q 点的水平距离最远，最远 距离是多少？
数为 t，则周期为 T= t / 49 D. 摆线上端未固定牢，摆动过程中出现松动，使摆线增长。
12．(9 分) 铅笔笔芯主原料是由石墨和粘土组成。2B 铅笔笔芯含石墨量高,书写时黑度也高，对电 脑审题不易误判。HB 铅笔笔芯含粘土较高，使笔芯强度提高不易折断，但黑度也降低。小明 想了解这两种铅笔芯的导电性能差异，进行了如下实验。
固定一质量为 0.2kg，电量与小球电量相等的异性带电小球 B，则
A．支架对地面的压力大小为 1.95N
M
N
B．当 B 球带上异性电荷后，A 球会向右偏离原来的位置
C．NA 线的拉力大小为 1N D．MA 线的拉力大小为 1.1N ▲10.如图所示，波源 S 形成的简谐横波在均匀介质中向左、
A h
B
不考虑火星的自转及火星表面大气的影响，已知万有引力常量为G，则火星的质量M和火星的星球
半径RБайду номын сангаас别为
A． M
= v3T 4 128π 4Gt3
，R
=
vT 2 16π 2t
C．
M
=
v3T 4 1024π4G
t3
，
R
=
vT 2 32π2t
B． M
=
v3T 2 128π 4Gt3
，
R
=
vT 16π 2t
D．
A
B
C
D
图甲
图乙
第 11 题图
春晖中学高二年级（3 月）限时训练（一） 第 3页（共 6 页）
（2）在做“利用单摆测重力加速度”的实验时，先测出 摆球的直径如图丙所示，直径 d 为 ▲ mm。 （3）实验测得的 g 值比实际值偏大，可能的原因是 （ ▲ ）。
A. 摆球的密度过小 B. 单摆实验不慎使单摆做圆锥摆运动 C. 摆球经平衡位置时启动秒表并开始计数，当摆球第 50 次经过平衡位置时制动秒表，若读
40V，额定输出功率 240W．由于电动机发热造成损耗，电动机的效率为
80%，不考虑其它部件的摩擦损耗。已知人与车的总质量为 76.8kg，自行
车运动时受到阻力恒为 38.4N，自行车保持额定功率从静止开始启动加速
到最大速度所前进的距离为 10m，下列正确的是
A．额定工作电流为 5A，电源内阻为 1.6Ω
子完全被吸收。重力不计。求：（sin53°=0.8，
cos53°=0.6）
（1）粒子的速率；
B
（2）被下极板吸收的粒子占总粒子的百分比。 U
A
第 15 题图
春晖中学高二年级（3 月）限时训练（一） 第 6页（共 6 页）
（1）求导体棒获得最大的速度 vm ； （2）导体棒从静止开始达到某一速度 v1，滑过的距离为 x0 ，导体棒 ab 发热量 Q ，求电源提供的
电能及通过电源的电量 q；
15.（14 分）如图所示，在半径 R=6cm 的圆形区域内，有一方向垂直纸面向外的匀强磁场，磁感
应强度 B=1T，其右侧放置长度 L=20cm，间距 d=20cm 的相互平行的金属板，它们的左侧边界线
为 m 、电阻同为 r 的导体棒 ab
垂直导轨方向静止置于上面，与导 轨接触良好。电路中其余位置电阻 均忽略不计。导体棒在导轨上运动 时将受到恒定的阻力 f，重力加速
度为 g。调节磁场的磁感应强度， 闭合开关 K ，使导体棒获得最大的
速度。 (需考虑导体棒切割磁感线产生的反电动势)
春晖中学高二年级（3 月）限时训练（一） 第 5页（共 6 页）
C．法拉第通过大量电和磁关系的实验研究，终于发现了电流周围存在磁场
D．楞次通过分析大量实验事实后确定了感应电流方向的定律
2．如图所示，经过专业训练的杂技运动员进行爬杆表演。质量为 60kg 的运动员爬上 8m 高的固定
竖直金属杆，然后双腿加紧金属杆倒立，头顶离地面 7m 高，
运动员通过双腿对金属杆施加不同的压力来控制身体的运动情
春晖中学高二年级（3 月）限时训练（一）
一、选择题(1-8 单选，4 分每题，9-10 多选，全对得 4 分，选对但不全得 2 分，共计 40 分）
1．在物理学的发展史上，许多科学家付出了努力。下列说法符合史实的是
A．牛顿经过了大量的数据推演和模型创设，提出了行星的三大运动定律
B．库仑通过实验测定了静电力常数 k的具体数值
v2 B
v3 C
第 5 题图
D 300
6．如图所示，手摇发电机产生正弦式交流电，通过一台理想变压器向定值电阻 R 供电。理想电
压表和电流表的示数分别为 U 和 I。当发电机转速增大，使发电机的输出电压变为原来的 2 倍，
正确的是 A．电压表的示数仍为 U。 B．电流表 A 的示数仍为 I。
A
~
V
R
C．通过电阻 R 的电流的频率增大。 D．电阻 R 消耗的功率变为原来的 2 倍。
M
=
v3T 4 1024π4G
t2
，
R
=
vT 32π2t
4．如图所示是一个绳长为 L 的球摆，将小球拉离平衡位置到 A 点使细绳
与竖直方向成 37°角，然后在 O 点的正下方距 O 点 d 处固定一颗钉子，再
将小球从 A 点静止释放。设绳子不可伸长，忽略小球的大小以及一切阻力，
下列说法正确的是
A．当 d=0.8L 时，小球向右摆动的过程中不能到达与 A 点等高处
B．自行车电动机的内阻为 5Ω
C．自行车加速的时间为 7s
第 8 题图
D．自行车保持额定功率匀速行驶的最长时间约为 2.4h
春晖中学高二年级（3 月）限时训练（一） 第 2页（共 6 页）
▲9．如图所示，两条等长细线的 A 点悬挂一质量为 0.1kg，电量为 2×10-6C 的带电小球，细线与
天花板的夹角为 30°，A 离地面 h=0.3m，在 MA 的延长线上用一不计高度和质量的绝缘支架
B. P、Q 两质点运动的方向始终相反 C. 当 S 恰好通过平衡位置向上运动时，Q 在波峰