16学年下学期高二第十七周周练物理试题(附答案)

广东省汕头市金山中学15—16学年下学期高二第十七周周练

物理试题

一、单项选择题

1. 运动员跳伞将经历加速下降和减速下降两个过程．将人和伞看成一个系统，在这两个过程中，下列说法正确的是( )．

A ．阻力对系统始终做负功

B ．系统受到的合外力始终向下

C ．加速下降时，重力做功大于系统重力势能的减小量

D ．任意相等的时间内重力做的功相等

2. 如图所示，操场两边放着半径分别为r1、r2，质量分别为m1、m2的篮球和足球，二者的间距为r ，则这两球间的万有引力大小为

A ．221r m m G

B ．212

1r m m G C ．()22121r r m m G + D ．()

2

2121r r r m m G ++ 3. 图中，AB 、AC 两光滑斜面互相垂直，AC 与水平面成30o ，如把球O 的重力按照其作用效果分解，则两个分力的大小分别为

A ．

21G ，23G B ．33G ，3G C ．32G ，22G D ．22G ，2

3G 4. 一个质量为m 的滑块，以初速度v 0沿光滑斜面向上滑行，当滑块从斜面底端滑到高为h 的地方时，以斜面底端为参考平面，滑块的机械能是

A ．

2021mv B ．Mgh C ．mgh mv +2021 D ．mgh mv -202

1 5. 如图所示,光滑水平面OB 与足够长粗糙斜面BC 交于B 点．轻弹簧左端固定于竖直墙面,现将质量为m 1的滑块压缩弹簧至D 点,然后由静止释放,滑块脱离弹簧后经B 点滑上斜面,上升到最大高度,并静止在斜面上．不计滑块在B 点的机械能损失；换用相同材料质量为m 2的滑块( m 2>m 1 )压缩弹簧到相同位置，然后由静止释放，下列对两滑块说法正确的是

A ．两滑块到达

B 点的速度相同 B ．两滑块沿斜面上升的最大高度相同

C ．两滑块上升到最高点过程机械能损失不相同

D ．两滑块上升到最高点过程克服重力做的功相同

6. 如图，可视为质点的小球A 、B 用不可伸长的细软轻线连接，跨过固定在地面上半径为R 的光滑圆柱，A 的质量为B 的两倍．当B 位于地面时，A 恰与圆柱轴心等高．将A 由静止释放，B 上升的最大高度是

A ．2R

B ．5R/3

C ．4R/3

D ．2R/3

7. 用长为L 的细绳拴着质量为m 的小球在竖直平面内做圆周运动，则下列说法中正确的是（ ）

A ．小球在圆周最高点时所受的向心力一定为重力

B ．小球在最高点时绳子的拉力不可能为零

C ．若小球刚好能在竖直平面内做圆周运动，则其在最高点的速率为gL

D ．小球过最低点时绳子的拉力一定小于小球重力，

8. 如图所示，在某路段汽车向左拐弯，司机左侧的路面比右侧的路面低一些。汽车的运动可看作是做半径为R 的圆周运动。设内外路面高度差为h ，路基的水平宽度为d ，路面的宽

度为L 。已知重力加速度为g 。要使车轮与路面之间的横向摩擦力（即垂直于前进方向）等于零.则汽车转弯时的车速应等于 ( )

A. B. C. D.

9. 如图所示，车内绳AB 与绳BC 拴住一小球，BC 水平，车由原来的静止状态变为向右加速直线运动，小球仍处于图中所示的位置，则（ ）

A ．A

B 绳、B

C 绳拉力都变大 B ．AB 绳拉力变大，BC 绳拉力变小 C ．AB 绳拉力变大，BC 绳拉力不变

D ．AB 绳拉力不变，BC 绳拉力变大 二、多项选择题

10. 如图所示，一个匀速转动的半径为r 的水平圆盘上放着两个木块M 和N ，木块M 放在圆盘的边缘处，木块N 放在离圆心

3

1

r 的地方，它们都随圆盘一起运动。比较两木块的线速度和角速度，下列说法中正确的是（ ）

A ．两木块的线速度相等

B ．两木块的角速度相等

C ．M 的线速度是N 的线速度的3倍

D ．M 的角速度是N 的角速度的3倍。

11. 已成为我国首个人造太阳系小行星的嫦娥二号卫星，2014年2月再次刷新我国深空探测

最远距离纪录，超过7000万公里。嫦娥二号是我国探月工程二期的先导星，它先在距月球表面高度为h 的轨道上做匀速圆周运动，运行周期为T ；然后从月球轨道出发飞赴日地拉格朗日L 2 点进行科学探测。若以R 表示月球的半径，引力常量为G ，则 A ．嫦娥二号卫星绕月运行时的线速度为

()T

r R +π2

B ．月球的质量为()2

3

24GT

h R +π C ．物体在月球表面自由下落的加速度为2

24T R

π

D ．嫦娥二号卫星在月球轨道经过减速才能飞赴拉格朗日L 2 点

12. 一物体从高h 处自由下落，落至某一位置时其动能与重力势能恰好相等（取地面为零势能面）

A ．此时物体所处的高度为h/2

B ．此时物体的速度为gh

C ．这段下落的时间为

g

h 2 D ．此时机械能可能小于mgh 13. 下列说法正确的是

A ．第一宇宙速度是在地球表面附近环绕地球运转的卫星的最大速度

B ．第一宇宙速度是同步卫星的环绕速度

C ．第一宇宙速度是从地面上发射人造卫星的最小发射速度

D ．卫星从地面发射时的发射速度越大，则卫星距离地面的高度就越大，其环绕速度则可能大于第一宇宙速度

14. 光滑的水平轨道AB ，与半径为R 的光滑的半圆形轨道BCD 相切于B 点，其中圆轨道在竖直平面内，B 为最低点，D 为最高点．一质量为m 的小球以初速度v 0沿AB 运动，恰能通过最高点，则（ ）

A ．R 越大，v 0越大

B．R越大，小球经过B点后的瞬间对轨道的压力越大

C．m越大，v0越大

D．m与R同时增大，初动能E k0增大

三、非选择题

15. 用如图甲的装置验证机械能守恒定律．

①除了图甲所示的实验器材，以及学生电源、导线和电键之外，还需要什么器材：______（填“天平”、“秒表”或“刻度尺”）．

②请完成下列主要实验步骤：

A．将打点计时器接到学生电源的______（填“直流”或“交流”）输出端；

B．先______，后释放悬挂纸带的夹子，计时器打出一条纸带．

③图乙是该实验中得到的一条纸带，两个计数点间的距离数据如图，时间间隔T=0.1s．则D点对应的速度v D=______m/s．（计算结果保留3位有效数字）

④由于______使机械能有损失，得出的实验结果，重锤重力势能减少量△E p______（填“小于”、“等于”或“大于”）动能的增加量△E k．

16. （1）GPS全球定位系统导航卫星绕地球运行的周期为T，地球半径用R表示，地球表面的重力加速度为g，求此卫星高地面高度h。

（2）有一种叫“飞椅”的游乐项目，示意图如图所示，长为L的钢绳一端系着座椅，另一端固定在半径为r的水平转盘边缘，转盘可绕穿过其中心的竖直轴转动．当转盘以角速度ω匀速转动时，钢绳与转轴在同一竖直平面内，与竖直方向的夹角为θ，重力加速度g。不计钢绳的重力，求：转盘转动的角速度ω与夹角θ的关系。

17. 与固定在圆心处的力传感器相连，小球和传感器的大小均忽略不计．当在A 处给小球6m/s 的初速度时，恰能运动至最高点B ，设空气阻力大小恒定，g=10m/s 2，求：

（1）小球在A 处时传感器的示数；

（2）小球从A 点运动至B 点过程中克服空气阻力做的功；

（3）小球在A 点以不同的初速度v 0开始运动，当运动至B 点时传感器会显示出相应的读数F ，试通过计算在图乙坐标系中作出F-v 02图象．

参考答案

1A 2D 3A 4A 5D 6C 7C 8B 9D 10BC 11AB 12AB 13AC 14AD

16. （1）R

T gR h -=3

2

2

24π （2）θθωsin tan L r g += 17. （1）F=10N （2）W 克f =0.8J （3）94

12

0-=

v F

2017-2018学年高二年级周练二英语试卷

江西省安义中学2017-2018学年度上学期高二英语第二次周练试卷 第一节阅读理解 Life is not easy in senior high school. You’ve got the pressure of studies and exams. From time to time, you may feel depressed and frustrated. When depression strikes, you have to take measures to fight it. One of the strangest ways to fight depression is to eat salt, scientists have found. Salt acts as a natural anti—depressant (抗抑郁剂), researchers say. While too much can lead to high blood pressure and heart disease, not enough can cause “psychological(心理的) d epressions”, a study has reported. The study, by researchers at the University of Iowa in the US, discovered that when rats are deficient in salt, they don’t do activities they normally enjoy. The recommended daily salt intake for an adult is four grams, although experts say the body needs only half as much. However, most adults in the developed world consume（消耗）around ten grams a day, mainly because their diets contain high salt amounts. Today, 77 percent of US salt intake comes from processed and restaurant foods, like frozen dinners and fast food. The minerals in salt are required by the body—in small quantities—to help move liquid in and out of cells. But too much can cause diseases, for example high blood pressure. Today scientists are finding that salt is an addictive substance—almost like a drug. One s ign of addiction is using a substance even when it’s known to be harmful. Many people are told to eat less salt due to health concerns, but they have trouble doing so because they like the taste and find low-salt foods tasteless. Humans have a long histor y of eating salt. In the Stone Age, people didn’t need to find salt, because they hunted most of their food, and ate a lot of red meat, which has plenty of salt in it. But when people began to farm, about 10,000 BC, they started to eat mainly grains like rice and wheat, and very little meat. Then they had to find another way to get salt. 1. What does the underlined word "deficient" in the third paragraph mean? A. enough B. far from enough C. more than enough D. plenty 2. The major role of salt is to ____________. A. help the body work well B. help fight against depression C. help people get rid of an addiction to drugs D. help people enjoy sugary substances 3. Which of the following statements is true? A. People have trouble reducing salt because they don't know it is harmful to eat too much of it. B. Before 10,000 BC, human beings did not need salt. C. The richer the country is, the more salt is eaten there. D. Taking more than 4 grams of salt a day can be harmful for an adult's health. 4. What kind of food should people eat more of? A. Frozen food B. Fast food C. Red meat D Low--salt food 第二节：七选五 Everyone knows that the Frenchmen are romantic, the Italians are fashionable and the Germans are serious. Are these just stereotypes(刻板印象) or is there really such a thing as national character? And if there is, can it affect how a nation succeed or fail? At least one group of people is certain that it can. A recent survey of the top 500 entrepreneurs (企业家) in the UK found that 70% felt that their efforts were not appreciated by the British public. Britain is hostile (敌意的) to success, they said. It has a culture of jealousy(嫉妒)．__5__ Jealousy is sometimes known as the “green－eyed monster” and the UK is its home. Scientists at Warwich University in the UK recently tested this idea. They gathered a group of people together and gave each an imaginary amount of money.__6__ Those given a little were given the chance to destroy the large amount of money given to others— but at the cost of losing their own. Two thirds of the people tested agreed to do this. __7__. But there is also opposite evidence. The Organization for Economic Cooperation and Development recently reported that the UK is now the world's fourth largest economy. That is not bad for people who are supposed to hate success. People in the UK also work longer hours than anyone else in Europe. So the British people are not lazy, either. “It is not really success that the British dislike,” says Carey Cooper, a professor of management at the University of Manchester Institute of Science and Technology. “It’s people using their success in a way that seems proud or unfair or which separates them from their roots.” _8__ They set out to do things in their way. They work long hours. By their own efforts they become millionaires.__9__ It hardly seems worth following their example. If they were more friendly, people would like them more. And more people want to be like them. A. This seems to prove that the entrepreneurs were right to complain. B. The one who owns most money in the end is the winner.

高二英语周练

高二英语周练 第一节完形填空(共20小题；每小题1.5分，满分30分) 阅读下面短文，掌握其大意。然后从各题所给的四个选项中，选出最佳选项Nowadays many people enjoy 1 activities—walking, cycling or mountaineering. People often 2 the act of climbing high and difficult mountains to be astonishing. Why are men and women 3 to suffer cold and hardship, and to 4 on high mountains? This astonishment may be caused by the difference between mountaineering and other forms of activities to which men 5 their leisure time. There are no man-made rules, as there are for 6 sports as golf and football. There are, of course, principles of different kinds. It would be dangerous if you 7 them. But it is this freedom from man-made rules 8 makes mountaineering attractive to many people. Those who climb mountains are free to choose their own 9 . If we 10 mountaineering with other more familiar sports, we might think that one big difference is that mountaineering is not a kind of 11 work at all. 12 , it is only our misunderstanding. There are n o “matches” 13 “teams” of climbers, but when climbers are on a rock face linked by a rope which their lives may 14 , there is obviously teamwork. A mountain climber knows that he may have to fight with natural 15 that are stronger and more powerful than man. A mountain climber 16 to improve his skill year after year. A skier has probably passed his best by the age of thirty, and most tennis champions 17 in their early twenties. But it is not 18 for men of fifty or sixty to climb the highest mountains in the Alps. They may take more 19 to do that than younger men, but they probably climb more skillfully and with less effort, and they certainly experience equal 20 . 1. A. physical B. easy C. difficult D. mental 2. A. find B. respect C. treat D. consider 3. A. scared B. willing C. afraid D. suitable 4. A. have a break B. make sense C. take a risk D. lose weight 5. A. give B. hope C. discover D. receive 6. A. so B. various C. different D. such 7. A. applied B. worried C. ignored D. noticed 8. A. which B. that C. how D. why 9. A. methods B. tradition C. styles D. activities 10. A. contact B. relate C. replace D. compare 11. A. pair B. complex C. team D. simple 12. A. Otherwise B. Therefore C. Furthermore D. However 13. A. between B. within C. from D. beyond 14. A. keep on B. go on C. depend on D. focus on 15. A. storms B. forces C. energies D. strengths 16. A. tries B. wants C. continues D. decides 17. A. will be B. are C. appear D. is 18. A. unusual B. normal C. common D. frequent 19. A. gifts B. means C. brains D. time 20. A. astonishment B. ambition C. concern D. enjoyment 第二部分阅读理解阅读下面短文，从每题所给的A, B, C, D四个选项中，选出最佳选项。(共20小题, 每小题2分, 满分40分) A

2018学年高二数学下学期周练2

云南省云天化中学2017-2018学年高二数学下学期周练2 一、填空题 1..已知5件产品中有2件次品,其余为合格品.现从这5件产品中任取2件, 恰有一件次品的概率为( ) A.0.4 B.0.6 C.0.8 D.1 2.执行如题图所示的程序框图，若输出k 的值为8， 则判断框内可填入的 条件是（ ） A. 34s ≤ B. 56s ≤ C. 1112 s ≤ D. 2524s ≤ 3.已知函数f(x)=Acos(ωx+φ)(A>0,ω>0,φ∈R),则“f(x)是奇函数”是“2π?= ”的( ) A.充分不必要条件 B.必要不充分条件 C.充分必要条件 D.既不充分也不必要条件 4.已知命题:P x x R x 32,<∈?；命题231,:x x R x q -=∈?，则下列命题中为真命题的是（ ） A. p ∧q B.￢p ∧q C.p ∧￢q D.￢p ∧￢q 5.若不等式组20220,20x y x y x y m +-≤??+-≥??-+≥?表示的平面区域为三角形，且面积等于43，则m 的值为（ ） A 3- B 1 C. 43 D.3 6.为了解某社区居民的家庭年收入与年支出的关系,随机调查了该社区5户家庭,得到如下统计数据表: 根据上表可得回归直线方程=x+,其中=0.76,=- .据此估计,该社区一户年收入为15万元家庭的年支出为( ) A.11.4万元 B.11.8万元 C.12.0万元 D.12.2万元 二、填空题

7. 已知椭圆:E )0(122 22>>=+b a b y a x 的右焦点)0,3(F ，过点F 的直线交E 于A ，B 两点，若AB 的中点坐标为)1,1(-，则E 的方程为 . 8. O 为坐标原点，F 为抛物线C ：x y 242 =的焦点，P 为C 上一点，若24||=PF ，则△POF 的面积为 . 9.若函数x ax x x f 1)(2++=在),21(+∞是增函数，则a 的取值范围是 . 10.在ABC ? 中，120,B AB A == 的角平分线AD ，则AC = _________. 三、解答题 11.设等差数列{a n }的公差为d,前n 项和为S n ,等比数列{b n }的公比为q.已知b 1=a 1,b 2=2,q=d,S 10=100. (1)求数列{a n },{b n }的通项公式. (2)当d>1时,记n n n a c b = ,求数列{c n }的前n 项和T n . 12.已知函数222ln 2)(a ax x x x f +-+-=，其中0a >。 （Ⅰ）设()g x 是()f x 的导函数，讨论()g x 的单调性； （Ⅱ）证明：存在(0,1)a ∈，使得()0f x ≥在区间(1,)+∞内恒成立，且()0f x =在区间(1,)+∞内有唯一解。 参考答案 一、选择题 1.【解题指南】先对产品标号,然后列举出可能出现的结果,根据古典概型概率公式求出所求

2021年高二下学期英语周练试卷(尖子班重点班5.25) 含答案

丰城中学xx学年下学期高二英语周练试卷 2021年高二下学期英语周练试卷（尖子班重点班5.25）含答案 一、完形填空（共20小题，每小题2分，满分40分） Before my year abroad, everyone advised me to say “yes” to everything. They weren’t 1 . However, here in Germany, “I don’t mind” doesn’t seem to be an acceptable 2 . Neither does “I’ll do whatever you want to do” nor “Really, either way is fine by me”. It really is 3 yes or no. Despite having a huge smile on your face, most Germans will look at you 4 you’re unable to make a 5 , which of course isn’t true; we’re just bei ng really typically British. My first encounter (遭遇) of this was when I 6 the hotel for my first two nights in Germany. The 7 asked when I would like my breakfast in the morning. Being typically British, I replied saying whenever was 8 for her. She gave me a(n) 9 look and asked again. “No, when do you want to have 10 ? Er, OK ... err .... 8 am?” she smiled and I 11 quickly, “Only if that is12 for you though.” I knew about the British stereotype (模式化的形象) of 13 before I came abroad. However, I didn’t 14 how much truth there was to it until

2019-2020学年度第一学期高二英语周练试卷(含答案)

2019-2020学年度第一学期高二英语周练试卷 第二部分：阅读理解（共两节，满分40分） 第一节（共15小题；每小题2分，满分30分） 阅读下列短文，从每题所给的四个选项中，选出最佳选项。 A Well, parents, surprise! Lots of us are using Twitter and Facebook to find rides, and not just to school. It’s awkward to call a friend and ask for a ride, and half the time they’ll say, “Sorry, my car is full.” But with Twitter, you just tweet #Ashleys Pool Party and look for other people heading the same way. It may sound risky, but many teens stay within their own social circles to find rides, and don’t branch out beyond friends when asking on Twitter. For me, I only rideshare with people I know, but to some young people, especially those taking longer trips, stranger danger is less of a concern. The sharing economy got big during the recession（经济衰退）. It allows people to access more goods and services using technology, while also allowing them to share cost. And that technology, for me, is what the car was for my mom, a gateway to more freedom. According to the researchers at the University of Michigan, 30 years ago, eight in ten American 18-year-olds had a driver’s license. Today it’s six in ten. So it’s not that surprising that on my 16th birthday I wasn’t rushing to get a license. All I wanted was an iPhone. Juliet Schor (Sociology professor at Boston College) knows people of my age love being connected and for young people driving means they have to disconnect from their technology, and that’s a negative. So if they could sit in the passenger side and still be connected, that’s going to be a plus. To me, another plus is ridesharing represents something more than trying to save money. I see it as evidence that people still depend on each other. My generation shares their cars and apartments the way neighbors used to share cups of sugar. For the system to work, some of us still need our own cars. But until I get my own version of the silver Super Beetle, you can find me on Twitter. 21 The writer usually rideshares with _____. A. anyone heading the same way B. people he knows

高二下学期英语周周练3

高二下学期周周练之三 2010-05-16 完形填空。 A few days ago I got on a bus and took a window seat．The bus 36 was by the seashore and I was watching the sea waves．After a few minutes the bus got to the next 37．A boy and a girl got on the bus．They were 38 when the bus took off．I glanced at them curiously and realized all the window 39 were occupied．They could have sat down but not together．Suddenly a(n) 40 passed through my mind．I 41 and offered them my seat．The young lady 42 and said，“Thank you very much．”Then we 43 ways after I moved to another seat．I don’t 44 whether I got off the bus before them or not． Months passed by．One day I was standing at the same bus stop when I heard a 45，“Excuse me，Unc le，”I glanced in the 46 of it．It was a beautiful young charming gir1．Puzzled, I said，“I don’t think I 47 you．”She said，“But I do．Do you remember you gave us your window seat?”I said，“Maybe，but what is so 48 in that?”She said，“Unc1e，you simply 49 like God for me．If you hadn’t given up your seat that day，I wouldn’t have sat with my friend．Our sitting 50 helped us a misunderstanding that had been 51 us．Do you know we are geeing 52 at the end of next month?” “53!God bless both of you，”I replied．The young lady thanked me again and went on with he 54．I realized the importance of giving that day! I also found that small things could 55 great happenings in life． 36、A、destination B、route C、travel D、distance 37、A、town B、shore C、village D、stop 38、A、standing B、sitting C、speaking D、quarrelling 39、A、benches B、seats C、areas D、spaces 40、A、thought B、concern C、feeling D、opinion 41、A、got off B、stood up C、went back D、sat down 42、A、jumped B、frowned C、passed D、smiled 43、A、spent B、hoped C、parted D、1eft 44、A、remember B、decide C、care D、think 45、A、warning B、noise C、voice D、scream 46、A、point B、direction C、way D、place 47、A、know B、mind C、understand D、meet 48、A、mysterious B、strong C、great D、proud 49、A、contributed B、showed C、started D、acted 50、A、together B、away C、along D、aside 51、A、with B、against C、between D、within 52、A、married B、promoted C、connected D、lost 53、A、Terrible B、Possible C、Sorry D、Good 54、A、visit B、journey C、tour D、study 55、A、invent B、achieve C、get D、create

西南位育2016学年第二学期英语周练(五)

西南位育初三2016学年第二学期英语周练（五）

III. Complete the following passage with the words or phrases in the box. Each

novels, plays, travel books, and so on. And in reading books of this kind the important thing is to get on with the reading; to try to grasp (领会) __50__ the writer is going to tell you in the book as a whole (整体而言). This is __51__ if you stop and think over the meaning of every single word which happens to be unfamiliar (不熟悉). You can not enjoy a story if you stop lots of times on every page for __52__ words in the dictionary. You may even prevent __53__ from understanding the story as a whole by doing this. V. Complete the following sentence as required. 64. Tell Jerry the news when you see him, please. （否定句） Please ______ ______ Jerry the news when you see him. 65. I was born on June 4, 1992. （对划线部分提问） ______ ______ you born? 66. The detective discovered some important clues for the case. （改为被动语态） Some important clues for the case ______ ______ by the detective. 67. The poor child was so lucky that she received many books from the charity. (改为简单句) The poor child was ______ ______ to receive many books from the charity. 68. To stop wild animals getting close to us, we lit a fire in the forest. (保持句意不变) To ______ ______ wild animals, we lit a fire in the forest. 69. Did they forget to turn off the lights before leaving? I don’t know.(改为宾语从句) I don’t know ______ they ______ to turn off the lights before leaving. 70. Brush your teeth at least twice every day. （改为反义疑问句）

2020高二英语上学期周练8

山西省××市和诚高中2018-2019学年高二英语上学期周练8 时间：60分钟总分100分出题人： 2018年10月21日 一、完形填空（每题2分，共40分） A cactus(仙人掌)stood all alone in the desert, wondering why it was stuck in the middle of nowhere． “I do nothing but 1 here all day,” it sighed．“What 2 am I ? I'm the ugliest plant in the desert. I can't 3 any passing traveler with shade or juicy fruit．I don't see what I can do 4 ．”All it did was stand in the sun day after day, growing taller and fatter．Its spines grew longer and its leaves tougher…It truly was st range-looking． “I wish I could do something useful,” it 5 ．By day, eagles circled high overhead．“What can I do with my life?” the cactus called．Whether they heard or not, the eagles sailed 6 ． At night, the moon floated into the sky and 7 its pale light on the desert．“What good can I do with my life?” the cactus called．The moon only stared coldly as it went on its way． A lizard（蜥蜴）moved by, 8 a little trail （痕迹）in the sand with its tail．“What worthy thing can I do?” the cactus called．“You?” the lizard laughed, pausing a moment．“Worthy deed? Why, you can't do 9 ! You do nothing but get uglier every day．” And so it 10 year after year．At last the cactus grew 11 , and it knew its time was short．“Oh, God” it cried out, “I've 12 so long, and I've tried so hard． 13 me if I've failed to find something worthy to do．I am afraid that now it is too 14 .” But just then the cactus felt a strange stirring and unfolding．A flow of joy drove away all 15 . At its very tip, like a sudden crown, a beautiful 16 suddenly opened. 17 had the desert known such a blossom. Its fragrance went through the air far and wide and brought 18 to all passing by． In the desert, a voice was sounding．“You have waited long, and the heart which seeks（寻求）to do good will always bring something 19 to the world, something for which all can be happy ---- 20 for only a moment.” 1. A. lie B. sit C. sleep D. stand 2. A. good B. advantage C. use D. help 3. A. provide B. lend C. offer D. make 4. A. after all B. at last C. at all D. in all 5. A. smiled B. stated C. announced D. sighed 6. A. away B. out C. up D. down 7. A. turned B. threw C. lit D. burnt 8. A. sweeping B. running C. leaving D. passing 9. A. anything B. nothing C. something D. everything

高二数学下学期周练一

2012-2013学年度高二年级第二学期周练(一) 理 科 一、填空题：（本大题共10题，每小题5分，共50分） 1.12 (3x 展开式中1x -的项的系数为 . （用数字作答） 2.接种某疫苗后，出现发热反应的概率为0.80.现有5人接种该疫苗，至少有3人出现发热反应的概率为__________. 3. 若 n 的展开式中各项系数之和为64，则展开式中的常数项为 . 4.从20名男同学，10名女同学中任选3名参加体能测试，则选到的3名同学中既有男同学又有女同学的概率为 . 5.8 2 1(12)x x x ? ?+- ?? ?的展开式中常数项为 ．（用数字作答） 6.8名同学排成前后两排，每排4人.如果甲、乙两同学必须排在前排，丙同学必须排在后排，那 么不同的排法共有_____________种(用数字作答)． 7.若n ∈N *，且n 为奇数，则6n +C n 16n-1+…+C n n-16-1被8除所得的余数是 。 8.甲、乙、丙三人将参加某项测试，他们能达标的概率分别是0.8、0.6、0.5，则三人中至少有一人达标的概率是 . 9.将5名志愿者分配到3个不同的奥运场馆参加接待工作，每个场馆至少分配一名志愿者的方案种数为 . （用数字作答） 10.某校从8名教师中选派4名教师同时去4个边远地区支教（每地1人），其中甲和乙不同去，甲和丙只能同去或同不去，则不同的选派方案共有 种（用数字作答）. 二、解答题：（本大题共8题，共110分） 11. 求8展开式中的所有的有理项. 12.已知()()n m x x x f 4121)(+++= * (,)m n N ∈的展开式中含x 项的系数为36，求展开式中 含2x 项的系数最小值 13.某气象站天气预报的准确率为80%，计算（结果保留最简分数）： （1）5次预报中恰有2次准确的概率； （2）5次预报中至少有2次准确的概率； （3）5次预报中恰有2次准确，且其中第3次预报准确的概率. 14.已知甲盒内有大小相同的1个红球和3个黑球，乙盒内有大小相同的2个红球和4个黑球.现在从甲、乙两个盒内各任取2个球. (I)求取出的4个球均为黑色球的概率； (II)求取出的4个球中恰有1个红球的概率； (III)设ξ为取出的4个球中红球的个数，求ξ的分布列和数学期望. 15.为防止风沙危害，某地决定建设防护绿化带，种植杨树、沙柳等植物.某人一次种植了n 株沙柳，各株沙柳成活与否是相互独立的，成活率为p ，设ξ为成活沙柳的株数，数学期望3E ξ=，标准差V ξ （Ⅰ）求n ,p 的值并写出ξ的分布列； （Ⅱ）若有3株或3株以上的沙柳未成活，则需要补种，求需要补种沙柳的概率.