2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷(解析版)
每日一学:浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题_压轴题解答
每日一学:浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题_压轴题解答答案浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题_压轴题~~ 第1题 ~~(2020宁波.九上期中) 在平面直角坐标系中,正方形ABCD 的四个顶点坐标分别为A(-2,4),B(-2,-2),C(4,-2),D(4,4).(1) 填空:正方形的面积为;当双曲线(k≠0)与正方形ABCD 有四个交点时,k 的取值范围是.(2) 已知抛物线L : (a>0)顶点P 在边BC 上,与边AB ,DC 分别相交于点E ,F ,过点B 的双曲线 (k≠0)与边DC 交于点N.①点Q(m ,-m -2m+3)是平面内一动点,在抛物线L 的运动过程中,点Q 随m 运动,分别求运动过程中点Q 在最高位置和最低位置时的坐标.②当点F 在点N 下方,AE=NF ,点P 不与B ,C 两点重合时,求的值.③求证:抛物线L 与直线 的交点M 始终位于 轴下方.考点: 反比例函数图象上点的坐标特征;二次函数与一次函数的综合应用;二次函数的实际应用-动态几何问题;~~ 第2题 ~~(2020宁波.九上期中) 二次函数的图象如图,对称轴为x=1.若关于x 的一元二次方程x +bx ﹣t=0(为实数)在﹣1<x <4的范围内有解,则t 的取值范围是________ .~~ 第3题 ~~(2020宁波.九上期中) 如图,△ABC 中,∠BAC=60°,∠ABC=45°,AB=4,D 是线段BC 上的一个动点,以AD 为直径画⊙O 分别交AB ,AC 于E ,F ,连接EF ,则线段EF 长度的最小值为( )A . B . C . D . 22浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题_压轴题解答~~ 第1题 ~~答案:解析:答案:解析:~~ 第3题 ~~答案:D解析:。
浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷(解析版)
2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷试题卷 I一、完型填空(本题有15小题,每小题15分,共计15分)阅读下面文章,掌握大意,然后从A、B、C、D四个选项中选出最佳选项.1. There was once a young man who began to feel self﹣satisfied after some small achievements.One day, the young man took a walk with a (1)_______ man from the town. On the way the young man was bragging(吹嘘) about himself,(2)_______ the wise man didn't say a word. When they (3)_______ the top, the wise man asked, "Look down. What do you see ?" "I see trees, farmland, houses and people as (4)_______ as ants working in the fields," the young man said."What do you feel?" the wise man asked."Everything is (5)_______ me. I feel I rule the world," the young man answered.The wise man said (6)_______.After a minute,he asked the young man to look (7)_______."What do you see this time?" the wise man asked."I see(8)_______ flying around high mountains,the white clouds on the mountains and the(9)_______ sky above the white clouds," the young man answered.Then he asked the wise man's (10)_______. "I feel small and powerless," the wise man answered. "A person who knows to look upward can (11)_______ understand his position(位置).When a person knows the blue sky is always overhead, he won't be so (12)_______ as to believe he rules over the world or other people."The young man felt foolish for his (13)_______. From then on ,(14)_______ he began to feel as if the world owed(亏欠) him something, he looked up at the sky and remembered (15)_______ small he really was. Try to look upward when you feel too good about yourself.(1)A.busyzyC.wiseD.hard﹣working(2)A.ifB.butC.soD.or(3)A.got toB.got offC.arrived inD.got up(4)A.fatB.lightC.smallD.strong(5)A.belowB.aboveC.betweenD.against(6)A.EverythingB.anythingC.somethingD.nothing(7)A.upB.downC.outD.after(8)A.monkeysB.tigersC.chicksD.birds(9)A.redB.blueC.greenD.black(10)A.waysC.feelingsD.address(11)A.badlyB.angrilyC.hardlyD.clearly(12)A.cleverB.smartC.sillyeful(13)A.prideB.successC.luckD.smell(14)A.whateverB.wheneverC.whereverD.however(15)A.whyB.whereC.howD.what二、阅读理解(本题有15小题,每小题6分,共计30分)(1)Which problem is NOT mentioned in the passage?________A. Air pollution.B. Water pollution.C. Destruction of forests.D. Global warming..(2)How long will the lecture last?________A. For half an hour.B. For 80 minutesC. For an hour.D. For 120 minutes..(3)The passage is probably a(n)________?A. noticeB. poemC. diaryD. advertisement.When your pen is broken, you think that's the end of its life. You throw it away. Itthen joins tons of other garbage that is becoming a big problem in cities.Each day, about 10,000 tons of waste is produced in Guangzhou, and 17,000 tons of household waste is produced in Beijing. In other countries, the case is similar. "If you're like most of us, most Americans, you're making seven pounds (3.17kg) of trash a day," US writer Edward Humes told CNN. So, an American makes 102 tons of trash in a lifetime.If you simply throw away that broken pen, it goes to a landfill(垃圾填埋场) and is buried together with many other trash. To prevent polluting the groundwater, workers cover the trash with soil and keep it dry. And your pen will stay there for a long, long time, without having further use. But it could have a better destination: the recycling bin.Have you ever noticed the different colors of trash bins in the street? Many cities in China have been running a waste﹣sorting (垃圾分类) campaign. They divide trash into "recyclable waste" and "unrecyclable waste". So in Yiwu there are many "Little Yellow Dog" appearing all around the city, even in our campus.Recycling waste can save energy, reduce greenhouse gas, and keep space free for theunrecyclable trash. Take your pen as an example. At the recycling factory, its metal parts could be taken out and reused to make other things.But recycling is not enough, experts say. Making less waste in the first place is the way forward. "The best thing to do is just keep using your stuff for as long as you can," US writer Adam Minter told Time Out magazine.(1)How much trash does each American make every year on average?________A. 7 kgB. 3.17kgC. 102 tonsD. over 1 ton.(2)According to the story, how should we deal with broken pens?________A. Throw them away.B. Bury them in a landfill.C. Put them into a recycling bin.D. Give them to our friend..(3)Waste should be recycled because this can________.a. save energyb. produce greenhouse gasc. save landfill spaced. save waterA. abB. bcC. adD. ac.(4)What is the best way to reduce waste?________A. Recycle different kinds of waste.B. Keep using your things as long as you can.C. Keep waste inside your house.D. Tell people about the importance of recycling.Parents of very young children know this: You catch your child in the act of stealing the cookie﹣﹣the evidence of candy written on his or her face. However, you get a wide﹣eyed ________:" I didn't do it!"Learning to tell the truth, even at the risk of punishment, is an important part of moral (道德) development, and new research suggests it can take seven or more years for kids to get there.Early 2017 Professor Craig E.Smith published a study. He and his workmates chose 48 children between four and nine years of age. They told the kids a story about a boy or girl doing something wrong, such as taking a classmate's toy or candy, and then either lying about the wrong doing to a parent or confessing (承认) it. In each case, they asked the children, how would the child feel? How would the mother feel?The children's answers were generally divided according to age, which is in agreement with the stolen candy, lying and getting unpunished. They imagined the parent in the study would be angry with the child who confessed. However, the seven﹣to﹣nine﹣year ﹣olds were more likely (可能的) to think the child would feel better confessing thecrime and that the parent would have positive (积极的) feelings towards a confessor.Smith says, "kids of all ages who expect that a parent would feel happy about a child's confession are more likely to tell the truth rather than lie. Reward the honesty even if you feel you must punish the wrong action." He adds, what parents can learn from these studies is to listen calmly without getting angry right away when their child confesses.(1)What does the underlined word "denial" in Paragragh 1 mean?________A. 委屈B. 责备C. 否认D. 拒绝.(2)Paragragh 2 mainly tell us________.A. kids can't tell "right" from "wrong"B. it takes time for kids to learn to tell the truthC. it's wrong to punish kids for telling the truthD. all the kids are willing to confess to a bad act.(3)What did Smith and his workmates find in their study?________A. Older kids are more likely than younger children to confess to a bad act.B. Younger children are more likely than older kids to confess to a bad act.C. The four﹣to﹣five﹣year﹣olds would feel better confessing the crime.D. The seven﹣to﹣nine﹣year﹣olds thought parents would be angry with their confessions..(4)According to Professor Smith, what can parents learn from these studies?________A. Parents should at once punish the children who lied.B. Parents should tell children the wrongness of lying.C. Parents should never get angry after their children's confessions.D. Parents should show positive feeling about their children's confessions.I'm sure most people like music. Music can not only bring us wonderful enjoyment, but also bring us happiness when we are tired or sad. And many people have the habit of enjoying music when they are free. But to our surprise, one English school allows children to listen to music or even to have the TV on while they are studying, and they find it is helpful to improve the students' grades.According to a research at Millfield School in the UK, around 20% of teenagers work better with background music, and 10% ________when allowed to finish their work with short walks around the room while up to 80% can concentrate(集中注意)better if allowed to play with a small object.The research has made the school use a very new way, encouraging students to discover which learning styles suit them best, and then do their homework listening to music or evenlying down. Some parents don't believe, but many are now accepting it at home where children are allowed to do their homework with the television on."I prefer to work on the floor with music on," said Sam, a 13﹣year﹣old boy. "At first my parent thought I didn't study hard, but my teacher asked them to look at my homework and when they saw it was OK, they agreed at last."(1)What advantage of music hasn't been mentioned in the passage?________A. Music can bring us enjoyment.B. Music can bring us happiness.C. Music can make people excited.D. Music can help to improve students' grades..(2)What does the underlined word "excel" probably mean?________A. It means "be good at doing something".B. It means "do badly in doing something".C. It means "give up doing something".D. It means "play with something"..(3)Which of the following is true?________A.B. One fifth of the students can work better with background music.C. 20% can concentrate better if allowed to play with a small object.D. No parents accept the idea..(4)What can you infer from the passage?________A. The students at Millfield School are against the new idea of allowing children to listen to music.B. More and more parents will allow children to listen to music while doing homework.C. The new idea will spread all over the world.D. More and more children will realize the importance of working hard.三、任务型阅读(本题有5小题,每小题5分,共计5分)请仔细阅读习主席给青年的建议,从A到F的六个选项中选出符合各段主题的句子,完成题.(其中一项为多余选项.)President Xi encouraged the country's youth to study hard and take in the knowledge like sponge(海绵). Xi has valued the development of Chinese youth. Now, let's have a look at what he has said to us.(1)_______Youth is an important time to train a person's thinking and abilities, and young peopleshould be thirsty for knowledge and eager to learn about the new things.(2)_______Young people should have a good understanding of the history and progress of the Chinese people's hard work in modern times. They should give themselves away to the motherland,the people and the nation.(3)_______The road of life for young people is long. Along the way, there is sunshine as well as rains and winds, joy as well as sadness.(4)_______Young people should smile and never give up when facing difficulties. They should dare to dream and work very hard to realize their dreams.(5)_______Learning is necessary for young people's growth and progress. The qualities and abilities of young people will have a direct influence on realizing the Chinese Dream.号内所给汉语注释,写出空白处各单词的正确形式(每空一词).Do you know the________ (意思) of the word?Can you________ (重复) what you said just now? I didn't hear you clearly.It is________ (有礼貌的) to say "Excuse me" when you ask for help.Mark Twain is a________ (有幽默感的) writer.Tom is a shy boy and he is afraid of giving________ (讲话,发言) in public.Chinese is________ (广泛地) spoken now by many people in the world.The pieces are usually cute children or________ (生气勃勃的) characters.Americans can hardly________(避免) buying products made in China.We can understand him well because of his good________ (发音)."It was________ (精确地) what I needed," he said.B.根据短文内容,用方框中所给单词的适当形式填空,每词限用一次。
浙江省宁波市奉化区2019-2020学年九年级上学期期末数学试题(word无答案)
浙江省宁波市奉化区2019-2020学年九年级上学期期末数学试题(word无答案)一、单选题(★) 1 . 正五边形的每个外角度数为()A.B.C.D.(★★) 2 . 在同一平面上,外有一定点到圆上的距离最长为10,最短为2,则的半径是()A.5B.3C.6D.4(★★) 3 . 若将抛物线y=x 2平移,得到新抛物线,则下列平移方法中,正确的是()A.向左平移3个单位B.向右平移3个单位C.向上平移3个单位D.向下平移3个单位(★) 4 . 一个不透明的盒子装有个除颜色外完全相同的球,其中有4个白球.每次将球充分搅匀后,任意摸出1个球记下颜色后再放回盒子,通过如此大量重复试验,发现摸到白球的频率稳定在0.2左右,则的值约为()A.8B.10C.20D.40(★) 5 . 二次函数部分图象如图所示,有以下结论:① ;② ;③ ,其中正确的是()A.①②③B.②③C.①②D.①③(★) 6 . 如图,在中,点,,分别在边,,上,且,,若,则的值为()A.B.C.D.(★) 7 . 已知点,,,在二次函数的图象上,则,,的大小关系是()A.B.C.D.(★) 8 . 在圆内接四边形中,与的比为,则的度数为()A.B.C.D.(★★) 9 . 如图,在菱形中,已知,,以为直径的与菱形相交,则图中阴影部分的面积为()A.B.C.D.(★) 10 . 如图,为线段上一点,与交与点,,交与点,交与点,则下列结论中错误的是()A.B.C.D.(★) 11 . 如图,小江同学把三角尺含有角的一端以不同的方向穿入进另一把三角尺(含有角)的孔洞中,已知孔洞的最长边为,则三角尺穿过孔洞部分的最大面积为()A.B.C.D.(★★★★) 12 . 如图,平行四边形的四个顶点分别在正方形的四条边上. ,分别交,,于点,,,且.要求得平行四边形的面积,只需知道一条线段的长度.这条线段可以是()A.B.C.D.二、填空题(★) 13 . 若,则的值为__________.(★) 14 . 从,0,,,1.6中随机取一个数,取到无理数的概率是__________.(★★) 15 . 如图所示,某河堤的横断面是梯形,,迎水坡长26米,且斜坡的坡度为,则河堤的高为米.(★) 16 . 如图,的直径垂直弦于点,且,,则弦__________ .(★) 17 . 如图,已知点是函数图象上的一个动点.若,则的取值范围是__________.(★) 18 . 如图,已知等边的边长为4,,且.连结,并延长交于点,则线段的长度为__________.三、解答题(★) 19 . 计算:;(★) 20 . 小王准备给小李打电话,由于保管不善,电话本上的小李手机号中,有两个数字已经模糊不清,如果用,表示这两个看不清的数字,那么小李的号码为(手机号码由11个数字组成),小王记得这11个数字之和是20的整数倍.(1)求的值;(2)求出小王一次拨对小李手机号的概率.(★★) 21 . 某工厂生产某种多功能儿童车,根据需要可变形为图1的滑板车或图2的自行车,已知前后车轮半径相同,,,车杆与所成的,图1中、、三点共线,图2中的座板与地面保持平行.问变形前后两轴心的长度有没有发生变化?若不变,请写出的长度;若变化,请求出变化量?(参考数据:,,)(★) 22 . 如图,有一座圆弧形拱桥,它的跨度为,拱高为,当洪水泛滥到跨度只有时,就要采取紧急措施,若某次洪水中,拱顶离水面只有,即时,试通过计算说明是否需要采取紧急措施.(★★) 23 . 如图二次函数的图象与轴交于点和两点,与轴交于点,点、是二次函数图象上的一对对称点,一次函数的图象经过、(1)求二次函数的解析式;(2)写出使一次函数值大于二次函数值的的取值范围;(3)若直线与轴的交点为点,连结、,求的面积;(★★) 24 . 某商店经销一种学生用双肩包,已知这种双肩包的成本价为每个30元.市场调查发现,这种双肩包每天的销售量y(个)与销售单价x(元)有如下关系:y=﹣x+60(30≤x≤60).设这种双肩包每天的销售利润为w元.(1)求w与x之间的函数关系式;(2)这种双肩包销售单价定为多少元时,每天的销售利润最大?最大利润是多少元?(3)如果物价部门规定这种双肩包的销售单价不高于42元,该商店销售这种双肩包每天要获得200元的销售利润,销售单价应定为多少.(★★★★) 25 . 定义:有两个相邻内角和等于另两个内角和的一半的四边形称为半四边形,这两个角的夹边称为对半线.(1)如图1,在对半四边形中,,求与的度数之和;(2)如图2,为锐角的外心,过点的直线交,于点,,,求证:四边形是对半四边形;(3)如图3,在中,,分别是,上一点,,,为的中点,,当为对半四边形的对半线时,求的长.(★★) 26 . 如图1,在平面直角坐标系中,已知的半径为5,圆心的坐标为,交轴于点,交轴于,两点,点是上的一点(不与点、、重合),连结并延长,连结,,.(1)求点的坐标;(2)当点在上时.①求证:;②如图2,在上取一点,使,连结.求证:;(3)如图3,当点在上运动的过程中,试探究的值是否发生变化?若不变,请直接写出该定值;若变化,请说明理由.。
【附20套中考模拟试卷】浙江省宁波鄞州区五校联考2019-2020学年中考化学模拟试卷含解析
浙江省宁波鄞州区五校联考2019-2020学年中考化学模拟试卷一、选择题(本题包括12个小题,每小题3分,共36分.每小题只有一个选项符合题意)1.物质存放在烧杯中一段时间后,质量变大且变质的是①浓盐酸②浓硫酸③烧碱④食盐⑤生石灰⑥稀硫酸A.①⑥B.②③⑤C.③⑤D.②③④2.用“W”型玻璃管进行微型实验,如下图所示。
下列说法不正确的是A.a处红棕色粉末变为黑色B.a处的反应为CO +Fe2O3=2Fe+CO2C.b处澄清石灰水变浑浊证明有CO2生成D.可利用点燃的方法进行尾气处理3.下列实验基本操作中,错误的是( )A.稀释浓硫酸B.滴加液体C.检验氧气D.称氢氧化钠固体4.下列关于“化学与生活”的认识不正确的是()A.在食品加工中,加入大量的食品添加剂,使食品既保鲜又美观B.食用铁强化酱油,有助于预防缺铁性贫血C.抵制使用一次性塑料袋,有利于长沙市创建文明城市D.回收处理废旧电池,有利于长沙市“两型”社会的建设5.归纳法是学习化学的重要方法之一,如图所示正确的是为( )A.B.C.D.6.下列各组物质的鉴别方法与结论均正确的是选项物质方法与结论A 黄铜与铜相互刻画,留下痕迹的是黄铜B 高锰酸钾与二氧化锰取样加热,伸入带火星木条复燃的是高锰酸钾C 氯化钠与硝酸铵取样溶解,试管外壁有水雾的是氯化钠D 稀盐酸与稀硫酸取样测pH,pH大的是稀盐酸A.A B.B C.C D.D7.下列说法中,正确的是()A.铁和铝在空气中都能形成致密的氧化物薄膜B.氧化钙和氢氧化钠固体都能作食品干燥剂C.浓盐酸和浓硫酸都有挥发性,敞口放置浓度都会变小D.二氧化碳和一氧化碳分子构成不同,化学性质不同8.木炭还原氧化铜和一氧化碳还原氧化铜的实验装置如下图所示。
下列说法正确的是A.木炭、一氧化碳与氧化铜的反应都属于置换反应B.两个实验的相关反应中,只有碳元素的化合价发生改变9.小雨的妈妈买了一条黄金项链,小雨想通过实验探究这条黄金项链是否为锌铜合金制成的仿制品,她不能选用的试剂是A.A1C13溶液B.Cu(NO3)2溶液C.H2SO4溶液D.AgNO3溶液10.下列实验现象的描述与事实不符的是()A.红磷在氧气中燃烧产生大量白烟B.氢气在空气中燃烧产生淡蓝色火焰C.二氧化碳通入紫色石蕊溶液中变蓝色D.打开盛有浓盐酸的试剂瓶后,瓶口出现白雾11.下列各组物质要借助酸碱指示剂才能判断反应发生的是A.石灰石和盐酸B.氧化铁和盐酸C.氢氧化钡和稀硫酸D.氢氧化钠和稀盐酸12.美国科学家卡尔•克利特在真空条件下,成功制得盐粒状的“氮5”(化学式为N5),在制取“氮5”的实验中,它曾发生了爆炸,摧毁了实验室的设备.因此科学家认为,如果能让这种物质保持稳定,它可以成为火箭和导弹的理想燃料.有关“氮5”的说法正确的是()A.“氮5”的化学性质非常稳定B.每个N5分子由5个氮原子构成C.“氮5”是一种化合物D.真空条件下“氮5”是一种气体二、填空题(本题包括4个小题,每小题7分,共28分)13.化学让我们知道了不少“是什么”和“为什么”。
浙江省宁波市奉化市2019-2020学年九年级下学期科学毕业生诊断性试卷及参考答案
浙江省宁波市奉化市2019-2020学年九年级下学期科学毕业生诊断性试卷一、选择题(本题共15小题,第1-10小题,每小题4分,第11-15小题,每小题3分,共55分。
请选出每小题中一个符合题意的选项,不选、错选均不给分)1. 2020年新型冠状病毒引发肺炎疫情在全球爆发,引起人们极大的关注。
查阅资料得知使用抗生素能够抑制细胞壁合成,下列有关说法中正确的是( )A . 新型冠状病毒是该病的传染源B . 勤洗手从传染病预防措施来看属于切断传播途径C . 使用抗生素可以有效治疗新冠肺炎D . 某位患者在某一时段体温维持在37.7℃,此时段他的产热大于散热2. 玻璃工艺如今做的越来越精美,在玻璃雕刻过程中用到的是氢氟酸,发生的反应为4HF+SiO =SiF ↑+nH O ,则下列说法正确的是( )A . SiO 中Si 的化合价为+2价B . 该反应属于置换反应C . 该反应前后原子总数不变D . 硅是地壳中含量最高的非金属元素3. 清澈平静的海面上空,一只海鸥与海平面呈75度角向下俯冲捕食,下列有关说法中正确的是( )A . 海鸥在海水中的像是由于光的折射形成的B . 俯冲过程中,海鸥与它的像距离逐渐增大C . 俯冲过程中,海鸥在海水中的像越来越大D . 海鸥和海水中像的连线与海平面始终垂直4.在我国的广西、福建、台湾,以及越南、印度等地生长着一种会跳舞的草,人们叫它舞草。
该植物茎单一或分枝,圆柱形,微具条纹,无毛。
种子长4-4.5mm ,宽2.5-3mm 。
花期7-9月,果期10-11月。
从以上信息中我们可以判断舞草属于( )A . 蕨类植物B . 苔藓植物C . 裸子植物D . 被子植物5. 小刚同学想利用下表中的液体进行科学探究,他选取了其中两种液体装入甲、乙两支试管中,将乙液体缓慢倒入甲中,发现混合液的pH 值随倒入乙液体质量变化如右图所示,则下列说法中错误的是( )物质厕所清洁剂柠檬汁橘汁酱油蒸馏水肥皂水草木灰浸出液PH 1.7 2.5 3.5 4.87.09.210.6A . 甲液体能使紫色石蕊试液变蓝色,乙可能是柠檬汁B . 甲液体可能是肥皂水,乙液体肯定呈酸性C . 甲液体可能是草木灰浸出液,乙液体可能是蒸馏水D . 乙液体和蒸馏水都不能使无色酚酞试液变红色6. 如图为月球表面拍摄的地球照片,图中地球的相貌为一轮满地(类似于满月),则当天地球上的人们看到的月相为( )A . 满月B . 上弦月C . 下弦月D . 新月7. 如图所示,三个相同的容器内水面高度相同,甲容器内只有水,乙容器内有木块漂浮在水面上,丙容器中悬浮着一个小球,则下列四种说法正确的是( )A . 三个容器对桌面的压强关系为p =p =pB . 三个容器中,乙容器中水对杯底的压力最大C . 如果向乙容器中加入盐水,木块所受浮力将变大D . 如果向丙容器中加入酒精,小球所受浮力将不变8. 下列对甲、乙、丙、丁四个实验的相关说法中,正确的是( )2422甲乙丙A . 向试管中滴加液体,正确的基本操作应如图甲所示,这样可保证将液体滴入试管B . 按图乙所示进行过滤操作,玻璃棒的倾斜角度不合适,这样很可能使液体外漏C . 如图丙所示,浓硫酸使白纸、木筷变黑,是因为浓硫酸吸收了纸和木筷中的水D . 图丁所示的三次读数,a 为俯视,b 读数方法正确,c 的读数比实际液体体积大9.在学习牛顿第一定律的时候,我们做了如下实验,下列叙述中错误的是( )A . 小车最终停止运动,说明力是维持物体运动的原因B . 每次实验,小车需要从斜面同一位置自由滑下C . 实验表明,小车所受阻力越小,运动距离越远D . 根据甲、乙、丙无法直接得出牛顿第一定律10. 图1所示装置可用于测定空气中氧气的含量,其中与广口瓶相连的压强传感器等电子设备能将广口瓶内气体压强精确地记录并保存下来。
浙江省宁波城区五校联考2019学年初三上数学月考试题及答案
(第6题图)(第5题图)(第8题图)(第9题图)2019学年第一学期初三数学月考试题(2019.12)温馨提示:本卷共26题,满分150分,考试时间120分钟,不能使用计算器.一.选择题(每题4分,共48分)1.点P (1,3)在反比例函数ky x=(0k ≠)的图象上,则k 的值是( ) A .13B .13- C .3D .3-2.如图,△ABC 的顶点都是正方形网格中的格点,则cos ∠ABC 等于( ) A.55 B.552 C.5 D.323. 抛物线y=3(x -2)2+1图象上平移2个单位,再向左平移2个单位所得的解析式为 ( ) A .y=3x 2+3 B .y=3x 2-1 C .y=3(x -4)2+3 D . y=3(x -4)2-1 4. 某市气象局预报称:明天本市的降水概率为80%,这句话指的是( ) A.明天本市80%的时间下雨,20%的时间不下雨 B.明天本市一定下雨C.明天本市80%的地区下雨,20%的地区不下雨D.明天本市不下雨的可能性只有20%5.如图所示,给出下列条件:①B ACD ∠=∠; ②ADC ACB ∠=∠; ③AC ABCD BC=; ④2AC AD AB =∙.其中单独能够判定ABC ACD △∽△的有( )A .①②③④B .①②③C .①②④D .①②6.如图,直角坐标系中,两条抛物线有相同的对称轴,下列关系式中不正确...的是( ) A .m h =B .h n >C .n k >D .0,0>>k h7.从长度分别为3、6、7、9的4条线段中任取3条作三角形的边,能组成三角形的概率为( ) A .34B .12 C .13D .148.图中给出的直线b x k y +=1和反比例函数xk y 2=的图像,判断下列结论正确..的有( ) ①2k >b >1k >0; ②直线 b x k y +=1与坐标轴围成的△ABO 的面积是4; ③方程组⎪⎩⎪⎨⎧=+=xk y b x k y 21的解为⎩⎨⎧-=-=1611y x ,⎩⎨⎧==3222y x ; ④当-6<x <2时,有b x k +1>x k 2 . (第2题图)(第10题图) (第11题图) (第12题图) (第15题图) (第17题图)(第16题图)A.1个 B.2个 C.3个 D.4个9. 如图,用一块直径为a的圆桌布平铺在对角线长为a的正方形桌面上,若四周下垂的最大长度相等,则桌布下垂的最大长度x为()A.12aB.C.)1a D.(2a-10. 如图,AC是菱形ABCD的对角线,AE EF FC==,则S△BMN:S菱形ABCD的值是()A.34B.37C.38D.31011.如图,水平地面上有一面积为30π2cm的灰色扇形OAB,其中OA的长度为6cm,且OA与地面垂直.若在没有滑动的情况下,将图(甲)的扇形向右滚动至点A再一次接触地面,如图(乙)所示,则O点移动了()cmA. 11π B. 12π C. 10π + π12. 如图,将弧BC 沿弦BC折叠交直径AB于点D,若AD=6, DB=7,则BC的长是()二.填空题(每题4分,共24分)13.在围棋盒中有6颗黑色棋子和a颗白色棋子,随机地取出一颗棋子,如果它是白色棋子的概率是35,则a= ▲ .14.把底面直径为6㎝,高为4㎝的空心无盖圆锥纸筒剪开摊平在桌面上,摊平后它能遮住的桌面面积是▲㎝215.如图,在以AB为直径的⊙O中,点C是⊙O上一点,弦AC长6 cm,BC长8 cm,∠ACB 的平分线交AB于E,交⊙O于D.则弦AD的长是▲ cm.16.如图,坡面CD的坡比为BC上有一棵小树AB,当太阳光线与水平线夹角成60°时,测得小树的在坡顶平地上的树影BC是3米,斜坡上的树影CD则(第18题图)小树AB 的高是___▲ _米.17. 如图,在面积为24的菱形ABCD 中,E 、F 分别是边AD 、BC 的中点,点G 、H 在DC 边上,且GH =21DC .则图中阴影部分面积为 ▲ . 18.如图, Rt △ABC 的直角边BC 在x 轴上,斜边AC 上的中线BD 交y 轴于点E,双曲线ky x=(k>0)的图象经过点A.若△BEC的面积为,则k 的值为 ▲三.解答题(共8道大题,19—21题,每题8分,22—23题,每题9分,24题10分,25题12分,26题14分,共78分)19. (本题8分)(1)已知3a =5b =7c ,求cb cb a +-+2的值.(2)已知A BC∠∠∠,,是锐角ABC ∆的三个内角,且满足20=(,求C ∠的度数.20. (本题8分)已知图中的曲线是函数5m y x-=(m 为常数)图象的一支. (1)求常数m 的取值范围;(2)若该函数的图象与正比例函数2y x =图象在第一象限的交点 为A (2,n ),求点A 的坐标及反比例函数的解析式.21. (本题8分)如图所示的转盘,分成三个相同的扇形,指针位置固定,转动转盘后任其自由停止,其中的某个扇形会恰好停在指针所指的位置,并相应得到一个数(指针指向两个扇形的交线时,视为无效,重新转动一次转盘),此过程称为一次操作. (1)求事件“一次操作,得到的数恰好是0”发生的概率; (2)用树状图或列表法,求事件“两次操作,第一次操作得到的数 与第二次操作得到的数绝对值相等”发生的概率.x(第21题图)22.(本题9分)如图,点E 是矩形ABCD 中CD 边上一点,△BCE 沿BE 折叠为△BFE ,点F 落在AD 上.(1)求证:△ABF ∽△DFE(2)若△BEF 也与△ABF 相似,请求出CDBC的值 .23. (本题9分)如图,已知斜坡AB 长60米,坡角(即BAC ∠)为30°,BC ⊥AC ,现计划在斜坡中点D 处挖去部分坡体(用阴影表示)修建一个平行于水平线CA 的平台DE 和一条新的斜坡BE .(1)若修建的斜坡BE 的坡角(即BEF ∠)不大于45°,则平台DE 的长最多为多少米? (2)一座建筑物GH 距离坡角A 点27米远(即AG =27米),小明在D 点测得建筑物顶部H 的仰角(即DHM ∠)为30°,点B 、C 、A 、G 、H 在同一个平面内,点C 、A 、G 在同一条直线上,且HG ⊥CG ,问建筑物GH 高为多少米?24. (本题10分)如图,BC 是⊙O 的弦,OD ⊥BC 于E ,交BC ⌒ 于D ,点A 是优弧BmC 上的动点(不与B 、C 重合), BC =34,ED=2. (1)求⊙O 的半径;(2)求cos ∠A 的值及图中阴影部分面积的最大值.(第22题图)(第23题图)(第24题图)25. (本题12分)如图,在边长为24cm 的正方形纸片ABCD 上,剪去图中阴影部分的四个全等的等腰直角三角形,再沿图中的虚线折起,折成一个长方体形状的包装盒(A 、B 、C 、D 四个顶点正好重合于上底面上一点)。
【20套试卷合集】浙江省宁波鄞州区五校联考2019-2020学年物理九上期中模拟试卷含答案
2019-2020学年九上物理期中模拟试卷含答案一、选择题(每题2分)1.下列四种现象中属于扩散现象的是()A.我国北方地区频发的“沙尘暴天气”B.春天柳絮漫天飞舞C.气体压缩到一定程度后,难以再压缩D.端午节,粽叶飘香2.下列事例中,通过热传递改变物体内能的是()A.钻木取火B.双手互搓发热C.冬天用热水袋取暖D.铁丝反复弯折后发热3.下列说法正确的是()A.物体放出热量,温度一定降低B.物体内能增加,温度一定升高C.热传递中,热量从内能多的物体传给内能少的物体D.热传递中,热量从高温物体传给低温物体4.汽油机是由四个冲程不断循环而工作的,图中表示机械能转化为内能的冲程是:()A.B.C.D.5.下列四组物质中,通常情况下都属于导体的一组是()A.玻璃、陶瓷、人体B.水银、大地、石墨C.塑料、空气、橡胶D.盐水、煤油、蒸馏水6.如图所示为滑动变阻器的结构示意图,要使滑片P向左移动时连入电路的电阻变小,接线柱连接正确的是()A.B.C.D.7.如图所示,一带负电橡胶棒靠近用细线挂住的轻细吸管A端时,吸管发生了转动.对吸管A端带电性质判断正确的是()A.若相互吸引,一定带正电B.若相互吸引,一定带负电C.若相互排斥,一定带正电D.若相互排斥,一定带负电8.小强同学在做某电学实验时,按图连接好了电路,合上开关S后,发现两灯均不发光.为检测出电路故障,他将电压表接到灯L1两端来测量电压,发现电压表有明显示数,而电流表示数几乎为零,则电路故障可能是()A.灯L1短路 B.灯L1断路 C.灯L2短路 D.灯L2断路9.一段均匀的电阻线,接在6V的电源上,通过它们的电流为200mA.若将这段电阻线等分成3段后,并联接在原电源上,则此时电路中的总电流为()A.600mA B.0.18A C.1.8A D.1.2A10.根据欧姆定律可以得到R=,由此下列判断准确的是()A.导体的电阻跟加在它两端的电压成正比,电压为零时电阻就等于零B.导体的电阻跟通过它的电流成反比,没有电流通过时就没有电阻C.导体的电阻等于加在它两端电压跟通过它的电流的比值D.导体的电阻是导体本身的一种性质,与导体两端的电压和通过导体的电流无关11.下列措施中不能提高热机的效率是()A.用热值大的燃料B.提高热机的功率C.减少各种热损失D.燃烧更多的燃料12.如图所示的电路中,电源两端的电压保持不变,闭合开关S,将滑动变阻器的滑片P向右移,下列说法中正确的是()A.电流表A的示数变小B.电压表V l的示数不变C.电压表V2的示数变大D.电压表V l与电压表V2的示数之和保持不变二、填空题(每题3分)13.两滴水银靠近时,能自动结合成一滴较大的水银,这一事实说明分子之间存在着,物体不能无限地被压缩,说明分子间存在,一匙糖加入水中,能使整杯水变甜,这是现象,该现象说明,酒精和水混合后,总体积会,说明.14.已知水的比热容是4.2×103J/(kg•℃),质量为1kg的20℃的水,温度升高20℃,需要吸收J的热量.汽车发动机利用循环流动的水进行冷却,这是因为水的大,在相同条件下能带走较多的,所以冷却效果好.15.在物理学中常提到的“热”学,通常有“内能”“温度”和“热量”等含义,请将下列“热”的含义填入空格内.(1)今天天气很热,这里的“热”是指;(2)液体蒸发吸热,这里的“热”是指;(3)摩擦生热,这里的“热”是指.16.一台汽油机的转速是3000转/分钟,这台汽油机的活塞每秒钟经过个冲程,完成个工作循环,做了次功.17.汽油的热值是4.6×107 J/kg,它表示的物理意义是.现有5 kg汽油,完全燃烧2 kg汽油放出的热量是,剩下的3 kg汽油的热值是.18.一导体两端电压为3V时,通过的电流为0.3A,则此导体的电阻为Ω;当该导体两端电压为0时,导体的电阻为Ω.19.在如图所示的电路中,有三个开关S1、S2、S3,如果仅将开关S3闭合,S1、S2断开,则灯L1、L2联.如果将开关S1、S2闭合,S3断开,则灯L1、L2联.20.如图所示电路,当开关S闭合,甲、乙两表是电压表时,两表示数之比U甲:U乙=3:2,则R1:R2=;当开关S断开,甲、乙两表是电流表时,两表示数之比I甲:I乙=.21.某照明灯额定电压是36V,正常发光时灯丝电阻为24Ω,则照明灯的额定电流为A.如果电源电压是48V,为使照明灯正常发光,可以在电路中联一个阻值为Ω的电阻.22.如图电路中,当S1闭合、S2断开时,电压表的示数为2.5V;当S1断开、S2闭合时,电压表示数为6V,则灯L1两端电压为V,灯L2两端的电压为V,电源电压为V.三、作图题23.根据电路图连接实物图.24.如图所示器材,按要求连接实物,并在右侧方框中画出对应的电路图.要求:(1)L1与L2串联;(2)滑动变阻器的滑片向右滑动时,两只小灯泡同时变暗,电压表测小灯泡L2两端的电压.四、简答题25.在烈日炎炎的夏天,如果你赤脚走在沙滩上,会觉得砂子烫脚;再从沙滩走入河水中,则感到凉快舒服,这是为什么?五、计算题26.某物理兴趣小组的同学,用煤炉给10kg的水加热,同时绘制了如图所示的加热过程中水温随时间变化的图线,若在6min内完全燃烧了0.56kg的煤,煤的热值约为3×107J/kg,水的比热容为4.2×103J/(kg•℃),求:(1)煤完全燃烧产生的热量;(2)经过6min时间加热,水所吸收的热量;(3)煤炉烧水时的热效率.27.为了测定炉内的温度,先把铜块放入炉内加热到与炉温相同时取出,并立即放入水中,已知m铜=50g,c铜=0.39×103J/(kg•℃),水的质量为100g,初温为10℃,测得达到热平衡时的温度为49℃,不计热量损失,则炉内温度为多少?[水的比热容c水=4.2×103J/(kg•℃)].28.在如图电路中,R1=10Ω,R2=20Ω,闭合开关后,电流表的示数为0.3A.(1)电阻R1两端的电压是多少?(2)通过R2的电流是多少?六、实验题29.在“探究影响导体电阻大小的因素”实验中,某实验小组提出了如下猜想:猜想一:导体电阻跟导体的长度有关;猜想二:导体电阻跟导体的粗细有关;猜想三:导体电阻跟导体的材料有关.同学们想利用如图所示的电路和表中的导体验证上述猜想.(1)请将猜想一的实验设计思路补充完整.选取和相同、不同的导体,分别将其接入如图所示的电路中.通过比较电路中的大小,判断导体电阻的大小.(2)验证猜想三时,若需对比三个实验数据,则应从表中选取导体(填写导体代号)来进行实验.(3)本实验主要用的实验方法是.(4)如果把此实验中的电流表换成小灯泡,通过小灯泡的亮暗来判断电阻大小,是否科学?.为什么?.30.小明探究“并联电路中电流的关系”,设计了如图甲所示电路.(1)小明首先测量C点的电流,当刚正确连接完所有的导线,两个灯泡立即发光,电流表指针偏向零刻度线左方,其原因是和.(2)改进后,小明测出了C点的电流.接下来,小明准备测量A点的电流.请你在图乙中用笔画线代替导线,完成实物电路的连接.(已知L1的电流约0.3A)(3)实验结束后小明记录A、B、C各点的电流值如下表所示:根据表中数据,小明得出以下两个结论:①并联电路各支路电流相等;②.(4)请你对上述实验的不足之处进行评价,写出两点评价意见:①;②.31.某同学在做“比较不同液体吸热能力”的实验时,使用相同的电加热器给液体甲和乙加热(2)分析第2、3次或第5、6次实验数据,可以得出的初步结论是:同种物质升高相同温度时,物质的越大,吸收的热量就越.(选填:“多”或“少”)(3)通过比较第2、4次实验数据可知,的吸热能力更强(选填“甲”或“乙”).(4)在探究物质比热容的实验中,我们得到了两个结论:不同质量的同种物质,吸收相同的热量,它们升高的温度;相同质量的不同物质,吸收相同的热量,它们升高的温度.32.在“探究电流与电压关系”的实验中,小明同学连接的电路如图所示.(1)在连接电路时,开关要处于(“断开”或“闭合”)状态,检查各处连线接触良好后,按照要求将变阻器的滑片P移至最端(选填“A”和“B”),试触开关时,会看到的现象是:电压表,电流表.(“有读数”或“无读数”)(2)根据试触时看到的现象,小明判断电路的连接存在某些错误,请你帮他检查电路,在图中改动一根接线,使得电路图变正确(在错误的一根连线上打“×”,然后画出正确的接线).小明同学利用如图所示的电路,进行探究电阻一定时,电流与电压的关系,得到的数据如表.(3)分析表中的数据,可以得出的结论是:.(4)滑动变阻器R在此实验中的主要作用是:a;b.参考答案与试题解析一、选择题(每题2分)1.下列四种现象中属于扩散现象的是()A.我国北方地区频发的“沙尘暴天气”B.春天柳絮漫天飞舞C.气体压缩到一定程度后,难以再压缩D.端午节,粽叶飘香【考点】扩散现象.【分析】(1)不同的物质相互接触时彼此进入对方的现象叫做扩散,扩散现象说明了组成物质的分子在不停地做无规则运动.(2)任何物质的分子间都存在引力和斥力.物质分子引力和斥力发生作用的距离是:当分子间距离小于10﹣10米时,分子间的作用力表现为斥力,当分子间距离大于10﹣10米时,分子间的作用力表现为引力.【解答】解:A、我国北方地区频发的“沙尘暴天气”,“沙尘”是肉眼可见的物体的运动,不属于分子运动,不符合题意;B、春天柳絮漫天飞舞,“柳絮”也是可见的物体的运动,不符合题意;C、气体压缩到一定程度后,由于分子间存在斥力,因此难以再压缩,与扩散无关,不符合题意;D、端午节粽叶飘香,是气体分子运动的结果,属于扩散现象,符合题意.故选D.2.下列事例中,通过热传递改变物体内能的是()A.钻木取火B.双手互搓发热C.冬天用热水袋取暖D.铁丝反复弯折后发热【考点】热传递改变物体内能.【分析】热传递是能的转移过程,即能量从高温物体向低温物体转移,在此过程中能的形式不发生变化;做功实质是能的转化过程,做功的过程中能量的形式改变了.【解答】解:A、钻木取火是通过做功的方式改变物体的内能,不合题意;B、双手互搓发热是通过做功的方式改变物体的内能,不合题意;C、冬天用热水袋取暖是通过热传递的方式改变物体的内能,符合题意;D、铁丝反复弯折后发热是通过做功的方式改变物体的内能,不合题意.故选C.3.下列说法正确的是()A.物体放出热量,温度一定降低B.物体内能增加,温度一定升高C.热传递中,热量从内能多的物体传给内能少的物体D.热传递中,热量从高温物体传给低温物体【考点】温度、热量与内能的关系.【分析】(1)物体吸收热量,内能一定增加,但有些物体的温度并不升高,例如晶体的熔化过程和液体的沸腾过程,不断吸收热量,但是温度保持熔点和沸点不变;(2)热量是一个过程量,存在于热传递过程中,只能说吸收或者放出热量,不能说含有或者具有热量;(3)热传递发生的条件是存在温度差异,热量由高温物体传递给低温物体,或者由同一个物体上的高温部分传递给低温部分,与物体自身内能的大小无关.【解答】解:A、物体放出热量,温度不一定降低,如晶体凝固时,放出热量,但温度不变,故A错误;B、物体内能增加,温度不一定升高,如晶体熔化时,吸热,内能增加,但温度不变,故B错误;CD、热传递中,热量从高温物体传给低温物体,而不是从内能多的物体传给内能少的物体,故C错误、D正确.故选D.4.汽油机是由四个冲程不断循环而工作的,图中表示机械能转化为内能的冲程是:()A.B.C.D.【考点】内燃机的四个冲程.【分析】本题应抓住汽油机的一个工作循环由如图所示的四个冲程组成:吸气冲程、压缩冲程、做功冲程、排气冲程.【解答】解:机械能转化为内能的冲程是:压缩冲程.A图:气门都关闭,活塞向上运行,气缸容积减小,是压缩冲程.符合题意.B图:排气门打开,活塞向上运动,气缸容积减小,是排气冲程.不符合题意.C图:气门都关闭,活塞向下运行,气缸容积增大,是做功冲程.不符合题意.D图:进气门打开,活塞向下运行,气缸容积增大,是吸气冲程.不符合题意.故选A.5.下列四组物质中,通常情况下都属于导体的一组是()A.玻璃、陶瓷、人体B.水银、大地、石墨C.塑料、空气、橡胶D.盐水、煤油、蒸馏水【考点】导体和绝缘体的区别.【分析】根据导体和绝缘体的定义:容易导电的物体是导体,不容易导电的物体是绝缘体即可作出判断.【解答】解:通常情况下常见的导体包括:人体、大地、各种金属、石墨、酸碱盐的溶液等.A、玻璃、陶瓷属于绝缘体,人体属于导体;B、水银、大地、石墨都属于导体;C、塑料、空气、橡胶都属于绝缘体;D、盐水属于导体,煤油、蒸馏水属于绝缘体.所以都属于导体的一组是B.故选B.6.如图所示为滑动变阻器的结构示意图,要使滑片P向左移动时连入电路的电阻变小,接线柱连接正确的是()A.B.C.D.【考点】滑动变阻器的使用.【分析】滑动变阻器的原理是靠改变连入电路中的电阻丝的长度来改变电阻的,它的正确接法是“一上一下”.哪一段电阻丝被接入电路中是由下面的接线柱决定的.若接左下接线柱,滑片向右移动,电阻变大;若接右下接线柱,滑片向左移动,电阻变大.【解答】解:A、图中连入电路中的是一个定值电阻(最大电阻),这种接法是不能变阻的,也就无法改变电流,故A不正确.B、图中连入电路中的电阻丝是左半部分.当滑片P向左滑动时,电阻丝长度变短,电阻变小,故B正确.C、图中连入电路的上面的金属杆,没有电阻丝接入电路,这种接法是不能变阻的,故C不正确.D、图中连入电路中的电阻丝是右半部分.当滑片向左滑动时,电阻丝长度变长,电阻变大,故D不正确.故选B.7.如图所示,一带负电橡胶棒靠近用细线挂住的轻细吸管A端时,吸管发生了转动.对吸管A端带电性质判断正确的是()A.若相互吸引,一定带正电B.若相互吸引,一定带负电C.若相互排斥,一定带正电D.若相互排斥,一定带负电【考点】物体带电现象.【分析】带电体能够吸引轻小物体;同种电荷相互排斥,异种电荷相互吸引.【解答】解:带电体能够吸引轻小物体,异种电荷相互吸引;带负电橡胶棒靠近用细线挂住的轻细吸管A端,若相互吸引,A端有可能不带电或带正电;故AB错误;若相互排斥,A端一定带负电,故C错误,D正确.故选:D.8.小强同学在做某电学实验时,按图连接好了电路,合上开关S后,发现两灯均不发光.为检测出电路故障,他将电压表接到灯L1两端来测量电压,发现电压表有明显示数,而电流表示数几乎为零,则电路故障可能是()A.灯L1短路 B.灯L1断路 C.灯L2短路 D.灯L2断路【考点】电流表、电压表在判断电路故障中的应用.【分析】此电路的故障可概括为:电压表有示数(L1处)而电流表(干路电流)无示数;说明电路中有电流通过,但很小,可根据这个观点进行分析、判断.【解答】解:将电压表接到L1两端时,电压表有示数,说明电路中有电流通过,即此电路为通路;而此时电流表示数几乎为零,说明了通过干路的电流很小;综合上面两点可知:灯L1断路,在L1两端接上电压表后,电路变为通路,但电压表的电阻很大,所以造成了电流表几乎没有示数,只有B选项符合情况;故选B.9.一段均匀的电阻线,接在6V的电源上,通过它们的电流为200mA.若将这段电阻线等分成3段后,并联接在原电源上,则此时电路中的总电流为()A.600mA B.0.18A C.1.8A D.1.2A【考点】欧姆定律的应用.【分析】首先根据R=求出电阻线的电阻,等分成3段后,每一段电阻丝的电阻变为原来的三分之一,并联后,求出并联后的总电阻,再根据I=求可出时最后的电流.【解答】解:电阻线的电阻为:R===30Ω,等分为三段后,每一段的电阻为:R1==10Ω,三等分后的电阻再并联,此时并联电路的总电阻为:R并==Ω,则此时电路中的总电流为:I总===1.8A.故选C.10.根据欧姆定律可以得到R=,由此下列判断准确的是()A.导体的电阻跟加在它两端的电压成正比,电压为零时电阻就等于零B.导体的电阻跟通过它的电流成反比,没有电流通过时就没有电阻C.导体的电阻等于加在它两端电压跟通过它的电流的比值D.导体的电阻是导体本身的一种性质,与导体两端的电压和通过导体的电流无关【考点】欧姆定律的变形公式.【分析】(1)电阻是导体本身的一种性质,只与导体的材料、长度、横截面积和温度有关,与两端的电压和通过的电流无关;(2)R=这个公式只说明导体电阻的大小是导体两端的电压与通过导体的电流大小的比值.【解答】解:电阻是导体本身的一种性质,只与导体的材料、长度、横截面积、温度有关,与导体两端的电压和通过的电流无关,故AB错误、D正确;由R=可知,导体的电阻等于加在它两端电压跟通过它的电流的比值,这只是计算导体电阻的一种方法,故C 正确.故选CD.11.下列措施中不能提高热机的效率是()A.用热值大的燃料B.提高热机的功率C.减少各种热损失D.燃烧更多的燃料【考点】热机的效率.【分析】热机效率是指用来做有用功的能量与燃料完全燃烧放出的能量之比,要提高热机的效率,就要提高燃料的利用率,减少热损失.【解答】解:A.采取热值大的燃料,其利用率不一定高,所以不一定能提高热机的效率,故A符合题意;B.提高热机的功率,增大热机在单位时间内做的功,其效率不一定提高,故B符合题意;C.减少各种热损失,可以提高热机的效率,故C不符合题意;D.燃烧更多的燃料,其利用率不一定高,所以不一定能提高热机的效率,故D符合题意.故选ABD.12.如图所示的电路中,电源两端的电压保持不变,闭合开关S,将滑动变阻器的滑片P向右移,下列说法中正确的是()A.电流表A的示数变小B.电压表V l的示数不变C.电压表V2的示数变大D.电压表V l与电压表V2的示数之和保持不变【考点】电路的动态分析;欧姆定律的应用.【分析】闭合开关S后,滑动变阻器R2与电阻R1串联,电流表测量电路中的电流,电压表V1测量R1两端的电压,电压表V2测量R2两端的电压;根据滑片的移动确定接入电路中电阻的变化,根据欧姆定律可知电路中电流的变化和定值电阻R1两端的电压变化,根据串联电路的电压特点可知滑动变阻器R2两端的电压变化以及电压表V l与电压表V2的示数之和的变化.【解答】解:由电路图可知,滑动变阻器R2与电阻R1串联,电流表测电路中的电流,电压表V1测R1两端的电压,电压表V2测R2两端的电压;将滑动变阻器的滑片P向右移时,接入电路中的电阻变大,电路中的总电阻变大,由I=可知,电路中的电流变小,即电流表A的示数变小,故A正确;由U=IR可知,定值电阻R1两端的电压变小,即电压表V l的示数变小,故B错误;因串联电路中的总电压等于各分电压之和,所以,滑动变阻器R2两端的电压变大,即电压表V2的示数变大,故C正确;因电压表V l与电压表V2的示数之和等于电源的电压,且电源的电压不变,所以,电压表V l与电压表V2的示数之和保持不变,故D正确.故选ACD.二、填空题(每题3分)13.两滴水银靠近时,能自动结合成一滴较大的水银,这一事实说明分子之间存在着引力,物体不能无限地被压缩,说明分子间存在斥力,一匙糖加入水中,能使整杯水变甜,这是扩散现象,该现象说明分子在做永不停息的无规则运动,酒精和水混合后,总体积会减小,说明酒精分子和水分子之间有间隙.【考点】分子动理论的基本观点.【分析】分子热运动理论的内容:一是物质是由分子构成的;二是构成物质的分子都在不停地做无规则运动;三是分子间存在相互作用力﹣﹣引力和斥力.不同物体互相接触时彼此进入对方的现象叫扩散,扩散现象说明分子在不停的做无规则运动.【解答】解:两滴水银能够自动结合成一滴较大的水银,是由于分子之间存在吸引力的缘故.物体的体积不能无限压缩,说明分子间有斥力.把糖加入到水中后,糖分子就会在水中发生扩散现象,扩散现象说明分子在做永不停息的无规则运动.正是由于酒精分子和水分子之间有间隙,才会导致混合合总体积变小故答案为:引力;斥力;分子在做永不停息的无规则运动;减小,酒精分子和水分子之间有间隙.14.已知水的比热容是4.2×103J/(kg•℃),质量为1kg的20℃的水,温度升高20℃,需要吸收8.4×104J 的热量.汽车发动机利用循环流动的水进行冷却,这是因为水的比热容大,在相同条件下能带走较多的热量,所以冷却效果好.【考点】热量的计算;水的比热容的特点及应用.【分析】(1)知道水的质量、水的温度变化、水的比热容,利用吸热公式求水吸收的热量;(2)因水的比热容比其它物质的比热容大,所以相同质量的水和其它物质比较,升高或降低相同的温度,水吸收或放出的热量多,据此分析.【解答】解:(1)水吸收的热量:Q吸=cm△t=4.2×103J/(kg•℃)×1kg×20℃=8.4×104J;(2)因为水的比热容较大,相同质量的水和其它物质比较,升高相同的温度,水吸收的热量多,能带走较多的热量,所以用水冷却发动机,冷却效果好.故答案为:8.4×104;比热容;热量.15.在物理学中常提到的“热”学,通常有“内能”“温度”和“热量”等含义,请将下列“热”的含义填入空格内.(1)今天天气很热,这里的“热”是指温度;(2)液体蒸发吸热,这里的“热”是指热量;(3)摩擦生热,这里的“热”是指内能.【考点】温度;热量的概念;内能的概念.【分析】根据三个物理量的概念进行分析.内能是指物体内部所有分子做无规则运动所具有的动能和分子势能的总和;温度指物体的冷热程度;热量是指在热传递或做功的过程中,内能改变的多少.【解答】解:(1)今天天气很热,很热是反映天气的冷热程度,所以这个“热”指温度;(2)液体蒸发吸热,是指液体吸收热量时温度升高,故这里的“热”指热量;(3)摩擦生热是通过克服摩擦做功,使物体的内能增加,所以这里的“热”指内能.故答案为:(1)温度;(2)热量;(3)内能.16.一台汽油机的转速是3000转/分钟,这台汽油机的活塞每秒钟经过100个冲程,完成25个工作循环,做了25次功.【考点】内燃机的四个冲程.【分析】在四冲程汽油机曲轴转一圈,完成2个冲程,1个工作循环中包括4个冲程并对外做功1次.【解答】解:汽油机的转速是3000r/min,即每秒钟转速为50r/s;在汽油机的一个工作循环中,曲轴转动2周,活塞往复运动2次,完成4个冲程,对外做功1次;所以汽油机1s内完成100个冲程,完成25个工作循环,做功25次.故答案为:100;25;25.17.汽油的热值是4.6×107 J/kg,它表示的物理意义是质量为1kg的汽油完全燃烧放出的热量是4.6×107J.现有5 kg汽油,完全燃烧2 kg汽油放出的热量是9.2×107J,剩下的3 kg汽油的热值是 4.6×107J/kg.【考点】燃料的热值;热量的计算.【分析】(1)根据热值的物理意义分析答题;燃料的热值是燃料的属性,不会随着质量的改变而改变;(2)根据Q放=mq即可求出汽油完全燃烧放出的热量.【解答】解:(1)汽油的热值是4.6×107J/g,其物理意义是:质量为1kg的汽油完全燃烧放出的热量是4.6×107J.热值是物体的特性,不随物质的量而变化,若汽油燃烧2kg后,剩余3kg汽油的热值仍为4.6×107J/kg.(2)完全燃烧2kg的汽油能放出的热量是:Q放=mq=2kg×4.6×107J/kg=9.2×107J.故答案为:质量为1kg的汽油完全燃烧放出的热量是4.6×107J;9.2×107J;4.6×107.18.一导体两端电压为3V时,通过的电流为0.3A,则此导体的电阻为10Ω;当该导体两端电压为0时,导体的电阻为10Ω.【考点】欧姆定律的应用;电阻;影响电阻大小的因素.【分析】(1)已知电阻两端的电压和通过导体的电流,根据欧姆定律的公式变形R=计算出导体的阻值;(2)导体的电阻是导体本身的一种性质,电阻大小取决于导体的材料、长度、横截面积,与两端的电压和通过的电流无关,据此可知当导体两端的电压改变时,电阻的阻值不变.【解答】解:(1)∵U=3V,I=0.3A,。
浙江省宁波市奉化区溪口中学2025届九年级物理第一学期期中学业质量监测模拟试题含解析
浙江省宁波市奉化区溪口中学2025届九年级物理第一学期期中学业质量监测模拟试题学期期中学业质量监测模拟试题注意事项:1.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.回答选择题时,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,再选涂其它答案标号。
回答非选择题时,将答案写在答题卡上,写在本试卷上无效。
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一、选择题(每题1.5分,共30题,45分)1.如图所示,水沸腾后会将软木塞冲开,其能量转化情况和四冲程内燃机的哪一个工作冲程相似()A.吸气冲程B.压缩冲程C.做功冲程D.排气冲程2.杜老师家的书房灯如图所示,共有6灯,两个开关,每个开关控制三盏灯,每盏灯的额定电压都是220V,电路应为A.B.C.D.3.以下温度中,最接近25℃的是()A.冰水混合物的温度B.健康成年人的体温C.让人感觉温暖而舒适的室内温度D.蜡烛外焰的温度4.在学过欧姆定律后,同学们有以下认识,其中不正确的是()A.欧姆定律揭示了导体中的电流与电压、电阻的关系B.当电压一定时,导体中的电流与电阻成反比C.在研究导体中的电流与电压、电阻的关系过程中使用了控制变量法D.根据欧姆定律的变形公式URI可知:导体的电阻随电压和电流的变化而变化5.如图所示,用与毛皮摩擦过的橡胶棒接触金属箔已张开的验电器的金属球,发现验电器的金属箔先闭合,后又张开,以下说法正确的是A.摩擦过程中创造了电荷B.验电器的金属箔开始时带负电荷C.验电器的工作原理是异种电荷相互排斥D.此过程中,瞬间产生的电流方向是从箔片流向橡胶棒6.滑动变阻器的工作原理是改变接入电路中电阻丝的A.长度B.粗细C.温度D.密度7.如图所示是四冲程汽油机一个工作循环中的三个冲程,缺少的一个冲程的名称及顺序,下列判断正确的是A.吸气冲程,应在甲图之前B.压缩冲程,应在甲、乙图之间C.做功冲程,应在乙、丙图之间D.排气冲程,应在丙图之后8.下列说法中正确的是()A.自由电子定向移动的方向为电流的方向B.木质铅笔里的石墨芯属于导体C.物体的内能增大,温度一定升高D.发生热传递的条件是两个物体含有的热量不同9.保护环境、节约能源要从我做起.下面的做法中,需要改正的是()A.及时关掉未关紧的水龙头B.尽可能用太阳能热水器代替电热水器C.及时将生活垃圾、废电池装在一起丢弃到垃圾箱中D.用洗脸水冲厕所,合理利用水资源10.下列做法中,使电阻丝的电阻变大的是A.把电阻丝拉长B.把电阻丝对折C.把电阻丝剪掉一段D.把电阻丝绕成螺丝管11.下面关于导体与绝缘体的说法正确的是A.绝缘体内没有电子所以不能导电B.导体内电荷都会发生移动,所以导体能导电C.导体容易导电靠的是自由电子D.绝缘体不易导电是因为内部的自由电荷很少12.如图所示电路,闭合开关,甲乙两灯均发光,两电表均有示数。
浙江省宁波鄞州区五校联考2019-2020学年中考数学模拟试卷
浙江省宁波鄞州区五校联考2019-2020学年中考数学模拟试卷一、选择题1.使两个直角三角形全等的条件是 A.一锐角对应相等 B.两锐角对应相等 C.一条边对应相等D.两条边对应相等2.下表是某水库一周内水位高低的变化情况(用正数记水位比前一日上升数,用负数记下降数).那么本周星期几水位最低( )3.只用下列一种正多边形不能镶嵌成平面图案的是( )A .正三角形B .正方形C .正五边形D .正六边形4.如图,正的边长为2,过点的直线,且与关于直线对称,为线段上一动点,则的最小值是( )A. B.2C. D.45.分式方程的解是( ) A.3B.-3C. D.96.如果340x y -=,那么代数式23()x y y x y-⋅+的值为( )A .1B .2C .3D .47.如图是某几何体的三视图,则该几何体的表面积为( )A .B .C .D .8.边长为2的正方形内接于⊙O ,则⊙O 的半径是( )A .1B C .2D .9.2019世界月季洲际大会4月28日将在中国某市举办!甲,乙,丙,丁四名同学将参加志愿者活动,若四名同学被随机分成两组,每组两人,则甲、乙恰好在同一组的概率是( )A .12B .13C .14D .1610.下列说法正确的是( )A .对角线互相垂直的四边形是平行四边形B .对角线相等且互相平分的四边形是矩形C.对角线相等且互相垂直的四边形是菱形D.对角线互相垂直的平行四边形是正方形11.下列图案,既是轴对称图形又是中心对称图形的有( )A.1个B.2个C.3个D.4个12.已知二次函数y=﹣(x﹣1)2+2,当t<x<5时,y随x的增大而减小,则实数t的取值范围是()A.t≤0B.0<t≤1C.1≤t<5 D.t≥5二、填空题13.不等式组112(3)33xx x+⎧⎨+->⎩…的解集是_____.14.计算的结果等于______.15.将一个四边形的纸片一刀剪去一个角后,所得的多边形的内角之和是_____.16.如图,AB是圆O的弦,AB=,点C是圆O上的一个动点,且∠ACB=45°,若点M、N分别是AB、BC的中点,则MN的最大值是_____.17.若点P(m,2)与点Q(3,n)关于x轴对称,则P点关于原点对称的点M的坐标为_____.18.如图,从多边形一个顶点出发作多边形的对角线,试根据下面几种多边形的顶点数、线段数及三角形个数统计结果,推断f,e,v三个量之间的数量关系是:______________多边形:顶点个数f1: 4 5 6 …线段条数e: 5 7 9 …三角形个数v1: 2 3 4 …三、解答题19.尺规作图(只保留作图痕迹,不要求写出作法)如图,已知∠a和线段a、b求作:(1)△ABC,使∠A=∠α,AB=a,AC=b.(2)在(1)的条件下,作AB边上的中线CD.20.已知矩形ABCD的一条边AD=8,将矩形ABCD折叠,使得顶点B落在CD边上的P点处.如图,已知折痕与边BC交于点O,连结AP、OP、OA.(1)求证:△OCP∽△PDA;(2)若tan ∠PAO =12,求边AB 的长.21.已知反比例函数ky x=的图象经过点P (2,3),函数y =ax+b 经过反比例函数图象上一点Q (1,m ),交x 轴于A 交y 轴于B (A ,B 不重合).(1)求出点Q 的坐标.(2)若OA =OB ,直接写出b 的值. 22.已知关于x 的二次函数y =﹣x 2+(k ﹣1)x+k . (1)试判断该函数的图象与x 轴的交点的个数;(2)求该函数的图象顶点M 的坐标(用k 的代数式表示); (3)当﹣3≤k<3时,求顶点M 的纵坐标的取值范围.23.计算:14011(2018)|12sin 602π-︒⎛⎫-+---+- ⎪⎝⎭24.如图,在等腰△ABC 中,AB =AC ,以AB 为直径的圆O 交BC 于点D ,过点C 作CF ∥AB ,与⊙O 的切线BE 交于点E ,连接DE . (1)求证:BD =CD ; (2)求证:△CAB ∽△CDE ;(3)设△ABC 的面积为S 1,△CDE 的面积为S 2,直径AB 的长为x ,若∠ABC =30°,S 1、S 2 满足S 1+S 2=x 的值.25.为弘扬“绿水青山就是金山银山”精神,某地区鼓励农户利用荒坡种植果树,某农户考察三种不同的果树苗A 、B 、C ,经引种试验后发现,引种树苗A 的自然成活率为0.8,引种树苗B 、C 的自然成活率均为0.9.(1)若引种树苗A 、B 、C 各10棵. ①估计自然成活的总棵数;②利用①的估计结论,从没有自然成活的树苗中随机抽取两棵,求抽到的两棵都是树苗A 的概率: (2)该农户决定引种B 种树苗,引种后没有自然成活的树苗中有75%的树苗可经过人工栽培技术处理,处理后成活的概率为0.8,其余的树苗不能成活.若每棵树苗引种最终成活后可获利300元,不成活的每棵亏损50元,该农户为了获利不低于20万元,问至少引种B 种树苗多少棵?【参考答案】***一、选择题13.0≤x<314.4x515.180°或360°或540°16.2017.(﹣3,﹣2)18.f+v-e=1三、解答题19.(1)如图,△ABC为所作;见解析;(2)如图,CD为所作;见解析.【解析】【分析】(1)先作∠BAC=∠α,然后分别截取AB=a,AC=b,从而得到△ABC;(2)作AB的中垂线得到AB的中点,从而得到中线CD.【详解】(1)如图,△ABC为所作;(2)如图,CD为所作.【点睛】本题考查作图﹣复杂作图:复杂作图是在五种基本作图的基础上进行作图,一般是结合了几何图形的性质和基本作图方法.解决此类题目的关键是熟悉基本几何图形的性质,结合几何图形的基本性质把复杂作图拆解成基本作图,逐步操作.20.(1)见解析;(2)AB=10.【解析】【分析】(1)只需要证明两对对应角分别相等即可证明相似(2)根据题①可知CP=4,设BO=x,则CO=8﹣x,PD=2(8﹣x),即可解答【详解】(1)证明:∵四边形ABCD为矩形,∴∠B=∠C=∠D=90°.由折叠,可知:∠APO=∠B=90°,∴∠APD+∠CPO=90°.∵∠APD+∠DAP=90°,∴∠DAP=∠CPO,∴△OCP∽△PDA;(2)解:由折叠,可知:∠APO=∠B=90°,AP=AB,PO=BO,tan∠PAO=POAP=BOAB=12.∵△OCP∽△PDA,∴12 PO OC CPAP PD DA===∵AD=8,∴CP=4.设BO=x,则CO=8﹣x,PD=2(8﹣x),∴AB=2x=CD=PD+CP=2(8﹣x)+4,解得:x=5,∴AB=10.【点睛】此题考查相似三角形的判定与性质和折叠问题,解题关键在于证明全等21.(1)Q点坐标为(1,6);(2)b=5或7.【解析】【分析】(1)根据待定系数法可求反比例函数的解析式,由点Q(1,m)在反比例函数kyx=的图象上,代入可求出点Q的坐标;(2)由题意OA=OB,可得直线y=ax+b的比例系数为1或﹣1,再分两种情况:①当a=1时,②当a=﹣1时,进行讨论可求b的值.【详解】如图:(1)将P(2,3)代入kyx=中得32k=,解得:k=6,∴反比例函数的解析式为6yx =,将点Q(1,m)代入6yx =,∴661m==,∴Q点坐标为(1,6);(2)由题意OA=OB,∴直线y =ax+b 的比例系数为1或﹣1, ①当a =1时,y =x+b ,将Q (1,6)代入得,6=1+b ,∴b =5, ∴解析式为y =x+5; ②当a =﹣1时,y =﹣x+b ,将Q (1,6)代入得,6=﹣1+b ,∴b =7, ∴解析式为y =﹣x+7. 【点睛】此题考查了反比例函数与一次函数的交点问题,此题要能够根据点在图象上求得待定系数的值,以及分类思想的运用.22.(1)1个或2个(2)(12k -,2(1)4k +)(3)当﹣3≤k<3时,顶点M 的纵坐标t 的取值范围为0≤t<4 【解析】 【分析】(1)计算判别式的值得到△=(k+1)2≥0,然后根据判别式的意义确定该函数的图象与x 轴的交点的个数;(2)利用配方法,把一般式配成顶点式即可得到该函数的图象顶点M 的坐标; (3)设顶点M 的纵坐标为t ,利用(2)的结论得到t =14(k+1)2,则t 为k 的二次函数,然后利用二次函数的性质求解. 【详解】解:(1)∵△=(k ﹣1)2﹣4×(﹣1)×k=k2+2k+1=(k+1)2≥0, ∴该函数的图象与x 轴的交点的个数为1个或2个; (2)∵y =﹣x 2+(k ﹣1)x+k222k 1k 1x (k 1)x k 22--⎡⎤--⎛⎫⎛⎫=--++⎢⎥ ⎪ ⎪⎝⎭⎝⎭⎢⎥⎣⎦221(1)=24k k x -+⎛⎫--+ ⎪⎝⎭ ∴该函数的图象顶点M 的坐标为2k 1(k 1),24⎛⎫-+ ⎪⎝⎭; (3)设顶点M 的纵坐标为t , 则t =14(k+1)2, 当k =﹣1时,t 有最小值0;当﹣3≤k<﹣1,t 随k 的增大而减小,则0<t≤1; 当﹣1<k <3时,t 随k 的增大而减小,则0<t <4, ∴t 的范围为0≤t<4,即当﹣3≤k<3时,顶点M 的纵坐标t 的取值范围为0≤t<4. 【点睛】本题考查了抛物线与x 轴的交点:把求二次函数y =ax 2+bx+c (a ,b ,c 是常数,a≠0)与x 轴的交点坐标问题转化为解关于x 的一元二次方程.△=b 2﹣4ac 决定抛物线与x 轴的交点个数(△=b 2﹣4ac >0时,抛物线与x 轴有2个交点;△=b 2﹣4ac =0时,抛物线与x 轴有1个交点;△=b 2﹣4ac <0时,抛物线与x轴没有交点).也考查了二次函数的性质.23.1【解析】【分析】直接利用零指数幂、负指数幂的性质以及绝对值的性质和特殊角的三角函数值分别化简得出答案.【详解】解:原式=11(2)12-+---=﹣﹣1=1.【点睛】此题主要考查了实数运算,正确应用整数指数幂和绝对值的性质化简各数是解题关键.24.(1)详见解析;(2)详见解析;(3)x=8..【解析】【分析】(1)因为AB=AC,欲证明BD=DC,只要证明AD⊥BC即可.(2)可以根据两角对应相等的两个三角形相似进行证明.(3)分别用x表示S1、S2,列出方程即可解决问题.【详解】(1)证明:∵AB是直径,∴∠ADB=90°,∴AD⊥BC,∵AB=AC,∴BD=CD.(2)∵AB∥CE,∴∠2=∠1,∵AB=AC,∴∠1=∠3,∵BE是⊙O切线,∴∠ABE=90°,∵AB∥CE,∴∠BEC+∠ABE=90°,∴∠BEC=90°,∵BD=DC,∴DE=DB=DC,∴∠2=∠4,∴∠3=∠2,∠1=∠4,∴△CAB∽△CDE.(3)∵S1=211x x224⋅=.∵△CAB∽△CDE,∴212432SS==,∴S2=216x,22x x+=∴x=±8,∵x>0,∴x=8.【点睛】本题考查圆的综合题、等腰三角形的判定和性质、相似三角形的判定和性质、平行线的性质等知识,解题的关键是灵活运用这些知识解决问题,属于基础题目,难度不大,是中考常考题型.25.(1)①自然成活的有26棵;②16;(2)至少引种B种树苗700棵.【解析】【分析】(1)①根据成活率求得答案即可;②列出树状图,利用概率公式求解即可;(2)设引B树苗x棵,则最终成活棵数为:0.9x+0.1x×0.75×0.8=0.96x,未能成活棵数为0.04x,利用农户为了获利不低于20万元列出不等式求解即可.【详解】解:(1)①10×0.8+10×0.9+10×0.9=26(棵),答:自然成活的有26棵;②在这12种情况下,抽到的2棵均为树苗A的有2种,∴P=16;(2)设引B树苗x棵,则最终成活棵数为:0.9x+0.1x×0.75×0.8=0.96 x,未能成活棵数为0.04 x 300(0.96 x)﹣50(0.04x)≥200000x≥100000143=69943143∴x=700棵答:该户至少引种B种树苗700棵.【点睛】本题考查了利用频率估计概率及列表法求概率的知识,解题的关键是能够正确的通过列树状图将所有等可能的结果列举出来,难度不大.。
2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校九年级(上)期中数学试卷(PDF版 含解析)
2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校九年级(上)期中数学试卷一、选择题:(每题4分,共48分)1.(4分)223y x x =-+的对称轴是直线()A .1x =-B .1x =C .1y =-D .1y =2.(4分)一个布袋中有4个红球与8个白球,除颜色外完全相同,那么从布袋中随机摸一个球是白球的概率是()A .112B .13C .23D .123.(4分)在Rt ABC ∆中,Rt C ∠=∠,3AC cm =,5AB cm =,若以C 为圆心,4cm 为半径画一个圆,则下列结论中,正确的是()A .点A 在圆C 内,点B 在圆C 外B .点A 在圆C 外,点B 在圆C 内C .点A 在圆C 上,点B 在圆C 外D .点A 在圆C 内,点B 在圆C 上4.(4分)如果将抛物线2y x =向上平移1个单位,那么所得抛物线对应的函数关系式是()A .21y x =+B .21y x =-C .2(1)y x =+D .2(1)y x =-5.(4分)已知圆弧的度数为120︒,弧长为6cm π,则圆的半径为()A .6cmB .9cmC .12cmD .15cm6.(4分)把一个小球以20米/秒的速度竖直向上弹出,它在空中的高度h (米)与时间t (秒),满足关系2205h t t =-,当小球达到最高点时,小球的运动时间为()A .1秒B .2秒C .4秒D .20秒7.(4分)如图,已知O 是ABD ∆的外接圆,AB 是O 的直径,CD 是O 的弦,58ABD ∠=︒,则BCD ∠等于()A .116︒B .32︒C .58︒D .64︒8.(4分)设1(2,)A y -,2(1,)B y -,3(1,)C y 是抛物线2(1)y x m =+-上的三点,则1y ,2y ,3y 的大小关系为()A .123y y y >>B .132y y y >>C .321y y y >>D .312y y y >>9.(4分)如图,将一把两边都带有刻度的直尺放在半圆形纸片上,使其一边经过圆心O ,另一边所在直线与半圆相交于点D 、E ,量出半径5OC cm =,弦8DE cm =,则直尺的宽度为()A .1cmB .2cmC .3cmD .4cm10.(4分)如图,已知抛物线2y ax bx c =++的顶点为(2,1)-,抛物线与y 轴的交点为(0,3),当函数值3y <时,自变量x 的取值范围是()A .02x <<B .03x <<C .04x <<D .13x <<11.(4分)如图是二次函数2y ax bx c =++图象的一部分,图象过点(3,0)A -,对称轴为直线1x =-,给出四个结论:①24b ac >;②20a b +=;③0a b c ++=;④5a b <.其中正确的个数有()A .1个B .2个C .3个D .4个12.(4分)如图,60BAC ∠=︒,45ABC ∠=︒,42AB =,D 是线段BC 上的一个动点,以AD 为直径画圆O 分别交AB ,AC 于E ,F ,连接EF ,则线段EF 长度的最小值为()A .22B .23C 3D 2二、填空题:(每题4分,共24分)13.(4分)二次函数22(2)3y x =-+图象的顶点坐标是.14.(4分)如图,在O 中, AC BD=,若40AOB ∠=︒,则COD ∠=︒.15.(4分)已知二次函数22y x x m =-++的部分图象如图所示,则关于x 的一元二次方程220x x m -++=的解为.16.(4分)抛物线21(1)22y m x x m =-++图象与坐标轴有且只有2个交点,则m =.17.(4分)如图,AD 是ABC ∆的高,且42AB =,5AC =,4AD =,则O 的直径是.18.(4分)二次函数2y x bx =+的图象如图,对称轴为直线1x =.若关于x 的一元二次方程20(x bx t t +-=为实数)在14x -<<的范围内有解,则t 的取值范围是.三、解答题(本大题有8小题,共78分)19.(6分)如图在平面直角坐标系中,ABC ∆的顶点坐标分别为(2,0)A ,(3,1)B ,(1,3)C ;(1)将ABC ∆沿x 轴负方向平移两个单位至△111A B C ,画图并写出点1C 的坐标;(2)以点1A 为旋转中心,将△11A B C 逆时针方向旋转90︒得△122A B C ,画图并写出点2C 的坐标.20.(8分)已知关于x 的二次函数2(1)3y x k x =+-+,其图象经过点(1,8).(1)求k 的值;(2)求出函数图象的顶点坐标.21.(8分)已知:如图,在O 中,AB CD =,AB 与CD 相交于点M .(1)求证: AC BD=;(2)求证:AM DM =.22.(10分)为了在校体育节的排球比赛上取得好成绩,甲、乙、丙、丁四人一起训练传接球.传接球规则如下:接球者把球随机传给另外三人中的一人.现由甲开始传球,请回答下列问题(假设每次传球都能接到球):(1)写出第一次接球者是乙的概率;(2)用列表或画树状图的方法求第二次接球者是甲的概率.23.(10分)如图,直线3y x =-+与x 轴,y 轴分别交于B ,C 两点,抛物线2y x bx c =-++经过B ,C 两点,点A 是抛物线与x 轴的另一个交点.(1)求出点B 和点C 的坐标.(2)求此抛物线的函数解析式.(3)在抛物线x 轴上方存在一点P (不与点C 重合),使PAB CAB S S ∆∆=,请求出点P 的坐标.24.(10分)某商品的进价为每件40元,当售价为每件50元时,每个月可卖出210件;如果每件商品的售价每上涨1元,则每个月少卖10件(每件售价不能高于65元).设每件商品的售价上涨x 元(x 为正整数),每个月的销售利润为y 元.(1)求y 与x 的函数关系式并直接写出自变量x 的取值范围;(2)每件商品的售价定为多少元时,每个月可获得最大利润?最大的月利润是多少元?(3)每件商品的售价定为多少元时,每个月的利润恰为2200元?25.(12分)如图:三角形ABC 内接于圆O ,BAC ∠与ABC ∠的角平分线AE ,BE 相交于点E ,延长AE 交外接圆O 于点D ,连接BD ,DC ,且60BCA ∠=︒(1)求BED ∠的大小;(2)证明:BED ∆为等边三角形;(3)若30ADC ∠=︒,圆O 的半径为r ,求等边三角形BED 的边长.26.(14分)在平面直角坐标系中,正方形ABCD 的四个顶点坐标分别为(2,4)A -,(2,2)B --,(4,2)C -,(4,4)D .(1)填空:正方形的面积为;当双曲线(0)ky k x=≠与正方形ABCD 有四个交点时,k 的取值范围是:;(2)已知抛物线2:()(0)L y a x m n a =-+>顶点P 在边BC 上,与边AB ,DC 分别相交于点E ,F ,过点B 的双曲线(0)ky k x=≠与边DC 交于点N .①点2(,23)Q m m m --+是平面内一动点,在抛物线L 的运动过程中,点Q 随m 运动,分别切运动过程中点Q 在最高位置和最低位置时的坐标;②当点F 在点N 下方,AE NF =,点P 不与B ,C 两点重合时,求BE CFBP CP-的值;③求证:抛物线L 与直线1x =的交点M 始终位于x 轴下方.2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校九年级(上)期中数学试卷参考答案与试题解析一、选择题:(每题4分,共48分)1.(4分)223y x x =-+的对称轴是直线()A .1x =-B .1x =C .1y =-D .1y =【解答】解:223y x x =-+ 的对称轴是直线2bx a=-,2121x -∴=-=⨯.故选:B .2.(4分)一个布袋中有4个红球与8个白球,除颜色外完全相同,那么从布袋中随机摸一个球是白球的概率是()A .112B .13C .23D .12【解答】解:因为共有12个球,抽到的可能性相同,其中是白球的可能性有8种,所以抽到白球的概率是82123=.故选:C .3.(4分)在Rt ABC ∆中,Rt C ∠=∠,3AC cm =,5AB cm =,若以C 为圆心,4cm 为半径画一个圆,则下列结论中,正确的是()A .点A 在圆C 内,点B 在圆C 外B .点A 在圆C 外,点B 在圆C 内C .点A 在圆C 上,点B 在圆C 外D .点A 在圆C 内,点B 在圆C 上【解答】解:由勾股定了得:222BC AB AC =-,∴4BC ==,∴若以C 为圆心,4cm 为半径画一个圆,点A 在圆C 内,点B 在圆C 上,故选:D .4.(4分)如果将抛物线2y x =向上平移1个单位,那么所得抛物线对应的函数关系式是()A .21y x =+B .21y x =-C .2(1)y x =+D .2(1)y x =-【解答】解: 抛物线2y x =向上平移1个单位后的顶点坐标为(0,1),∴所得抛物线对应的函数关系式是21y x =+.故选:A .5.(4分)已知圆弧的度数为120︒,弧长为6cm π,则圆的半径为()A .6cmB .9cmC .12cmD .15cm【解答】解:180n RL π= ,则18069120R ππ⨯==.故选:B .6.(4分)把一个小球以20米/秒的速度竖直向上弹出,它在空中的高度h (米)与时间t (秒),满足关系2205h t t =-,当小球达到最高点时,小球的运动时间为()A .1秒B .2秒C .4秒D .20秒【解答】解:22205520h t t t t =-=-+ 中,又50-< ,∴抛物线开口向下,有最高点,此时,2022(5)t =-=⨯-.故选:B .7.(4分)如图,已知O 是ABD ∆的外接圆,AB 是O 的直径,CD 是O 的弦,58ABD ∠=︒,则BCD ∠等于()A .116︒B .32︒C .58︒D .64︒【解答】解:AB 是O 的直径,90ADB ∴∠=︒,58ABD ∠=︒ ,9032A ABD ∴∠=︒-∠=︒,32BCD A ∴∠=∠=︒.故选:B .8.(4分)设1(2,)A y -,2(1,)B y -,3(1,)C y 是抛物线2(1)y x m =+-上的三点,则1y ,2y ,3y 的大小关系为()A .123y y y >>B .132y y y >>C .321y y y >>D .312y y y >>【解答】解: 函数的解析式是2(1)y x m =+-,∴对称轴是1x =-,∴点C 关于对称轴的点C '是1(3,)y -,那么点A 、B 、C '都在对称轴的左边,而对称轴左边y 随x 的增大而减小,于是312y y y >>.故选:D .9.(4分)如图,将一把两边都带有刻度的直尺放在半圆形纸片上,使其一边经过圆心O ,另一边所在直线与半圆相交于点D 、E ,量出半径5OC cm =,弦8DE cm =,则直尺的宽度为()A .1cmB .2cmC .3cmD .4cm【解答】解:过点O 作OF DE ⊥,垂足为F ,OF 过圆心,8DE cm = ,142EF DE cm ∴==,5OC cm = ,5OE cm ∴=,2222543OF OE EF cm ∴=-=-=.故选:C .10.(4分)如图,已知抛物线2y ax bx c =++的顶点为(2,1)-,抛物线与y 轴的交点为(0,3),当函数值3y <时,自变量x 的取值范围是()A .02x <<B .03x <<C .04x <<D .13x <<【解答】解: 抛物线2y ax bx c =++的顶点为(2,1)-,∴对称轴为2x =,抛物线与y 轴的交点为(0,3),∴当3y =时x 的值为0或4,∴当函数值3y <时,04x <<,故选:C .11.(4分)如图是二次函数2y ax bx c =++图象的一部分,图象过点(3,0)A -,对称轴为直线1x =-,给出四个结论:①24b ac >;②20a b +=;③0a b c ++=;④5a b <.其中正确的个数有()A .1个B .2个C .3个D .4个【解答】解:A .由函数图象可知240b ac ->,故24b ac >成立,则①正确;由对称轴1x =-知,12b a -=-,故2a b =,又因函数图象开口向下知0a <,故20a b +<,则②错误;由题目可知函数图象与x 轴的另一个交点是(1,0),故0a b c ++=,则③正确;由对称轴1x =-知,12b a -=-,故2a b =,又因函数图象开口向下知0a <,故52a a <,即5a b <成立,故④正确.故选项错误;B .由函数图象可知240b ac ->,故24b ac >成立,则①正确;由对称轴1x =-知,12b a-=-,故2a b =,又因函数图象开口向下知0a <,故20a b +<,则②错误;由题目可知函数图象与x 轴的另一个交点是(1,0),故0a b c ++=,则③正确;由对称轴1x =-知,12b a -=-,故2a b =,又因函数图象开口向下知0a <,故52a a <,即5a b <成立,故④正确.故选项错误;C .由函数图象可知240b ac ->,故24b ac >成立,则①正确;由对称轴1x =-知,12b a-=-,故2a b =,又因函数图象开口向下知0a <,故20a b +<,则②错误;由题目可知函数图象与x 轴的另一个交点是(1,0),故0a b c ++=,则③正确;由对称轴1x =-知,12b a -=-,故2a b =,又因函数图象开口向下知0a <,故52a a <,即5a b <成立,故④正确.故选项正确;D .由函数图象可知240b ac ->,故24b ac >成立,则①正确;由对称轴1x =-知,12b a-=-,故2a b =,又因函数图象开口向下知0a <,故20a b +<,则②错误;由题目可知函数图象与x 轴的另一个交点是(1,0),故0a b c ++=,则③正确;由对称轴1x =-知,12b a -=-,故2a b =,又因函数图象开口向下知0a <,故52a a <,即5a b <成立,故④正确.故选项错误;故选:C .12.(4分)如图,60BAC ∠=︒,45ABC ∠=︒,42AB =,D 是线段BC 上的一个动点,以AD 为直径画圆O 分别交AB ,AC 于E ,F ,连接EF ,则线段EF 长度的最小值为()A .B .CD 【解答】解:由垂线段的性质可知,当AD 为ABC ∆的边BC 上的高时,直径AD 最短,如图,连接OE ,OF ,过O 点作OH EF ⊥,垂足为H ,则EH FH =,在Rt ADB ∆中,45ABC ∠=︒,AB =42AD BD AB ∴===,即此时圆的直径为4,2OE ∴=,由圆周角定理可知1602EOH EOF BAC ∠=∠=∠=︒,∴在Rt EOH ∆中,sin 22EH OE EOH =∠=⨯=由垂径定理可知2EF EH ==.故选:B .二、填空题:(每题4分,共24分)13.(4分)二次函数22(2)3y x =-+图象的顶点坐标是(2,3).【解答】解: 二次函数的顶点式为22(2)3y x =-+,∴其顶点坐标为:(2,3).故答案为:(2,3).14.(4分)如图,在O 中, AC BD =,若40AOB ∠=︒,则COD ∠=40︒.【解答】解: 在O 中, AC BD=,∴AB CD =,40AOB ∠=︒ ,40COD AOB ∴∠=∠=︒.故答案为:40.15.(4分)已知二次函数22y x x m =-++的部分图象如图所示,则关于x 的一元二次方程220x x m -++=的解为11x =-或23x =.【解答】解:依题意得二次函数22y x x m =-++的对称轴为1x =,与x 轴的一个交点为(3,0),∴抛物线与x 轴的另一个交点横坐标为1(31)1--=-,∴交点坐标为(1,0)-∴当1x =-或3x =时,函数值0y =,即220x x m -++=,∴关于x 的一元二次方程220x x m -++=的解为11x =-或23x =.故答案为:11x =-或23x =.16.(4分)抛物线21(1)22y m x x m =-++图象与坐标轴有且只有2个交点,则m =1-或2或0.【解答】解: 抛物线21(1)22y m x x m =-++图象与坐标轴有且只有2个交点,而抛物线与y 轴始终有一个交点,∴与x 轴只有一个交点,∴△42(1)0m m =--=,1m ∴=-或2,另外当0m =时,22y x x =-+与x 轴的一个交点(0,0)正好是与y 轴的交点,即此时也与坐标轴只有两个交点,故答案为:1m =-或2或0.17.(4分)如图,AD 是ABC ∆的高,且AB =,5AC =,4AD =,则O 的直径是【解答】解:如图,连接AO 并延长交 于E ,连接BE .AE 是直径,AD BC ⊥,90ADC ABE ∴∠=∠=︒,C E ∠=∠ ,ADC ABE ∴∆∆∽,∴AC ADAE AB =,即5AE =AE ∴=,O ∴ 的直径为.18.(4分)二次函数2y x bx =+的图象如图,对称轴为直线1x =.若关于x 的一元二次方程20(x bx t t +-=为实数)在14x -<<的范围内有解,则t 的取值范围是18t -< ..【解答】解: 对称轴为直线121b x =-=⨯,2b ∴=-,∴二次函数解析式为22y x x =-.当1x =-时,123y =+=;当4x =时,16248y =-⨯=;当1x =时,121y =-=-.20x bx t +-= 相当于2y x bx =+与直线y t =的交点的横坐标,∴当18t -< 时,在14x -<<的范围内有解.故答案为:18t -< .三、解答题(本大题有8小题,共78分)19.(6分)如图在平面直角坐标系中,ABC ∆的顶点坐标分别为(2,0)A ,(3,1)B ,(1,3)C ;(1)将ABC ∆沿x 轴负方向平移两个单位至△111A B C ,画图并写出点1C 的坐标(1,3)-;(2)以点1A 为旋转中心,将△11A B C 逆时针方向旋转90︒得△122A B C ,画图并写出点2C 的坐标.【解答】解:(1)△111A B C 如图所示,点1(1,3)C -;(2)△122A B C 如图所示,点2(3,1)C --.故答案为:(1,3)-;(3,1)--.20.(8分)已知关于x 的二次函数2(1)3y x k x =+-+,其图象经过点(1,8).(1)求k 的值;(2)求出函数图象的顶点坐标.【解答】解:(1)把(1,8)代入二次函数2(1)3y x k x =+-+得:8113k =+-+解得:5k =;(2)把5k =代入二次函数得:243y x x =++,则2243(2)1y x x x =++=+-.∴二次函数得顶点坐标为(2,1)--.21.(8分)已知:如图,在O 中,AB CD =,AB 与CD 相交于点M .(1)求证: AC BD=;(2)求证:AM DM =.【解答】证明:(1) 在O 中,AB CD =,∴AB CD =,∴AB BC CD BC -=-,∴AC BD =;(2)连接AC ,BD ,AC BD=,AC BD ∴=,在ACM ∆和DBM ∆中,A D AC DBC B ∠=∠⎧⎪=⎨⎪∠=∠⎩,()ACM DBM ASA ∴∆≅∆,AM DM ∴=.22.(10分)为了在校体育节的排球比赛上取得好成绩,甲、乙、丙、丁四人一起训练传接球.传接球规则如下:接球者把球随机传给另外三人中的一人.现由甲开始传球,请回答下列问题(假设每次传球都能接到球):(1)写出第一次接球者是乙的概率;(2)用列表或画树状图的方法求第二次接球者是甲的概率.【解答】解:(1)P (第一次接球者是乙)13=;(2)画树状图如下:P ∴(第二次接球者是甲)3193==.23.(10分)如图,直线3y x =-+与x 轴,y 轴分别交于B ,C 两点,抛物线2y x bx c =-++经过B ,C 两点,点A 是抛物线与x 轴的另一个交点.(1)求出点B 和点C 的坐标.(2)求此抛物线的函数解析式.(3)在抛物线x 轴上方存在一点P (不与点C 重合),使PAB CAB S S ∆∆=,请求出点P 的坐标.【解答】解:(1)在直线3y x =-+中,当0x =时3y =,当0y =时3x =,(3,0)B ∴,(0,3)C ;(2) 抛物线2y x bx c =-++经过(3,0)B 、(0,3)C ,∴9303b c c -++=⎧⎨=⎩.∴解得:23b c =⎧⎨=⎩.∴此抛物线的解析式为223y x x =-++.(3)当0y =时,2230x x -++=,解得:11x =-,23x =.(1,0)A ∴-,设(P x ,)(0)y y >,PAB CAB S S ∆∆= ,∴1144322y ⨯⨯=⨯⨯,3y ∴=,当3y =时,2233x x -++=,解得:10x =,22x =,(0,3)P ∴或(2,3),点P 不与点C 重合,(2,3)P ∴.24.(10分)某商品的进价为每件40元,当售价为每件50元时,每个月可卖出210件;如果每件商品的售价每上涨1元,则每个月少卖10件(每件售价不能高于65元).设每件商品的售价上涨x 元(x 为正整数),每个月的销售利润为y 元.(1)求y 与x 的函数关系式并直接写出自变量x 的取值范围;(2)每件商品的售价定为多少元时,每个月可获得最大利润?最大的月利润是多少元?(3)每件商品的售价定为多少元时,每个月的利润恰为2200元?【解答】解:(1)2(21010)(5040)101102100(015y x x x x x =-+-=-++< 且x 为整数);(2)由(1)中的y 与x 的解析式配方得:210( 5.5)2402.5y x =--+.100a =-< ,∴当 5.5x =时,y 有最大值2402.5.015x < ,且x 为整数,当5x =时,5055x +=,2400y =(元),当6x =时,5056x +=,2400y =(元),∴当售价定为每件55或56元,每个月的利润最大,最大的月利润是2400元.(3)当2200y =时,21011021002200x x -++=,解得:11x =,210x =.∴当1x =时,5051x +=,当10x =时,5060x +=,∴当售价定为每件51元或60元,每个月的利润为2200元.25.(12分)如图:三角形ABC 内接于圆O ,BAC ∠与ABC ∠的角平分线AE ,BE 相交于点E ,延长AE 交外接圆O 于点D ,连接BD ,DC ,且60BCA ∠=︒(1)求BED ∠的大小;(2)证明:BED ∆为等边三角形;(3)若30ADC ∠=︒,圆O 的半径为r ,求等边三角形BED 的边长.【解答】解:(1)60BCA ∠=︒ ,180********BAC ABC BCA ∴∠+∠=︒-∠=︒-︒=︒,BAC ∠ 与ABC ∠的角平分线AE ,BE 相交于点E ,11()1206022ABE BAE BAC ABC ∴∠+∠=∠+∠=⨯︒=︒,60BED ABE BAE ∴∠=∠+∠=︒;(2)证明:60BCA ∠=︒ ,60ADB BCA ∴∠=∠=︒,180180606060DBE BED ADB ∴∠=︒-∠-∠=︒-︒-︒=︒,BED ∴∆为等边三角形;(3)30ADC ∠=︒ ,60ADB ∠=︒,306090BDC ADC ADB ∴∠=∠+∠=︒+︒=︒,BC ∴是O 的直径,60BCA ∠=︒ ,906030ABC ∴∠=︒-︒=︒,BE 平分ABC ∠,15CBE ∴∠=︒,601545DBC DBE CBE ∴∠=∠-∠=︒-︒=︒,cos 4522BD BC r ∴=︒== .即等边BED ∆.26.(14分)在平面直角坐标系中,正方形ABCD 的四个顶点坐标分别为(2,4)A -,(2,2)B --,(4,2)C -,(4,4)D .(1)填空:正方形的面积为36;当双曲线(0)k y k x =≠与正方形ABCD 有四个交点时,k 的取值范围是:;(2)已知抛物线2:()(0)L y a x m n a =-+>顶点P 在边BC 上,与边AB ,DC 分别相交于点E ,F ,过点B 的双曲线(0)k y k x=≠与边DC 交于点N .①点2(,23)Q m m m --+是平面内一动点,在抛物线L 的运动过程中,点Q 随m 运动,分别切运动过程中点Q 在最高位置和最低位置时的坐标;②当点F 在点N 下方,AE NF =,点P 不与B ,C 两点重合时,求BE CF BP CP-的值;③求证:抛物线L 与直线1x =的交点M 始终位于x 轴下方.【解答】解:(1)由点(2,4)A -,(2,2)B --可知正方形的边长为6,∴正方形面积为36;有四个交点时04k <<或80k -<<;故答案为36,04k <<或80k -<<;(2)①由题意可知,24m - ,2223(1)4Q y m m m =--+=-++,当1m =-,Q y 最大4=,在运动过程中点Q 在最高位置时的坐标为(1,4)-,当1m <-时,Q y 随m 的增大而增大,当2m =-时,Q y 最小3=,当1m >-时,Q y 随m 的增大而减小,当4m =时,Q y 最小21=-,321∴>-,Q y ∴最小21=-,点Q 在最低位置时的坐标(4,21)-,∴在运动过程中点Q 在最高位置时的坐标为(1,4)-,最低位置时的坐标为(4,21)-;②当双曲线k y x=经过点(2,2)B --时,4k =,(4,1)N ∴, 顶点(,)P m n 在边BC 上,2n ∴=-,2BP m ∴=+,4CP m =-,抛物线2()2(0)y a x m a =-->与边AB 、DC 分别交于点E 、F ,(2E ∴-,2(2)2)a m ---,(4F ,2(4)2)a m --,2(2)BE a m ∴=--,2(4)CF a m =-,∴22(2)(4)24BE CF a m a m BP CP m m ----=-+-,(2)(4)222(1)a m a m am a a m ∴+--=-=-,AE NF = ,点F 在点N 下方,226(2)3(4)a m a m ∴---=--,12(1)3a m ∴-=,1(1)4a m ∴-=,∴12BE CF BP CP -=;③由题意得,(1M ,2(1)2)a m --,2(1)2(24)M y a m m ∴=--- ,即2(1)2(24)M y a m m =--- ,0a > ,∴对应每一个(0)a a >值,当1m =时,M y 最小2=-,当2m =-或4时,M y 最大92a =-,当4m =时,2(4)2y a x =--,(4,2)F ∴-,(2,362)E a --,点E 在边AB 上,且此时不与B 重合,23624a ∴-<- ,106a ∴< ,12922a ∴-<--,12M y ∴- ,同理2m =-时,2(2)2y y a x ==+-,(2,2)E ∴--,(4,362)F a -,点F 在边CD 上,且此时不与C 重合,23624a ∴-<- ,解得106a < ,12922a ∴-<-- ,12M y ∴- ,综上所述,抛物线L 与直线1x =的交点M 始终位于x 轴下方;。
浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题
浙江省宁波市奉化区溪口中学、尚田中学等五校2019-2020学年九年级上学期期中数学试题一、单选题(共12题;共24分)1.抛物线y=x2﹣2x+3的对称轴是直线()A. x=﹣2B. x=2C. x=﹣1D. x=12.一个布袋中有4个红球与8个白球,除颜色外完全相同,那么从布袋中随机摸一个球是白球的概率是()A. B. C. D.3.在Rt△ABC中,∠C=90°,AC=3cm,AB=5cm,若以C为圆心,4cm为半径画一个圆,则下列结论中,正确的是()A. 点A在圆C内,点B在圆C外B. 点A在圆C外,点B在圆C内C. 点A在圆C上,点B在圆C外D. 点A在圆C内,点B在圆C上4.把抛物线向上平移1个单位长度得到的抛物线的表达式为()A. B. C. D.5.已知圆弧的度数为120°,弧长为6πcm,则圆的半径为()A. 6cmB. 9cmC. 12cmD. 15cm6.把一个小球以20米/秒的速度竖起向上弹出,它在空中的高度h(米)与时间t(秒),满足关系h=20t -5t ,当小球达到最高点时,小球的运动时间为()A. 1秒B. 2秒C. 4秒D. 20秒7.如图,已知⊙O是△ABD的外接圆,AB是⊙O的直径,CD是⊙O的弦,∠ABD=58°,则∠BCD等于()A. 116°B. 32°C. 58°D. 64°8.设A(-2,),B(-1,),C(1,)是抛物线上的三点,则,,的大小关系为()A. >>B. >>C. >>D. >>9.如图,将一把两边都带有刻度的直尺放在半圆形纸片上,使其一边经过圆心O,另一边所在直线与半圆相交于点D、E,量出半径OC=5cm,弦DE=8cm,则直尺的宽度是( )A. 4cmB. 3cmC. 2cmD. 1cm10.如图,已知抛物线的顶点为(2,-1),抛物线与y轴的交点为(0,3),当函数值时,自变量x的取值范围是()A. B. C. D.11.如图是二次函数y=ax2+bx+c图象的一部分,图象过点A(﹣3,0),对称轴为x=﹣1.给出四个结论:①b2>4ac;②2a+b=0;③a﹣b+c=0;④5a<b.其中正确的有()A. 1个B. 2个C. 3个D. 4个12.如图,△ABC中,∠BAC=60°,∠ABC=45°,AB=4 ,D是线段BC上的一个动点,以AD为直径画⊙O 分别交AB,AC于E,F,连接EF,则线段EF长度的最小值为()A. B. C. D.二、填空题(共6题;共7分)13.二次函数y=2(x-2)2+3图象的顶点坐标是________.14.如图,在⊙O中,,若∠AOB=40°,则∠COD=________.15.已知二次函数的部分图象如图所示,则关于的一元二次方程的根为________.16.抛物线y=(m﹣1)x2+2x+ m图象与坐标轴有且只有2个交点,则m=________.17.如图,AD是△ABC的高,且AB= ,AC=5,AD=4,则⊙的直径AE是________.18.二次函数的图象如图,对称轴为x=1.若关于x的一元二次方程x2+bx﹣t=0(为实数)在﹣1<x<4的范围内有解,则t的取值范围是________ .三、解答题(共8题;共74分)19.在平面直角坐标系中,已知A(2,0),B(3,1),C(1,3)①将△ABC沿x轴负方向平移2个单位至△,画图并写出的C1坐标。
2020-2021学年浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷含解析
2020-2021学年浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷试题卷I一、完型填空(本题有15小题,每小题15分,共计15分)阅读下面文章,掌握大意,然后从A、B、C、D四个选项中选出最佳选项.1. There was once a young man who began to feel self﹣satisfied after some small achievements.One day, the young man took a walk with a (1)_______ man from the town.On the way the young man was bragging(吹嘘)about himself, (2)_______ the wise man didn't say a word.When they (3)_______ the top, the wise man asked, "Look down.What do you see ? " "I see trees, farmland, houses and people as (4)_______ as ants working in the fields, " the young man said."What do you feel? " the wise man asked."Everything is (5)_______ me.I feel I rule the world, " the young man answered.The wise man said (6)_______.After a minute, he asked the young man to look (7)_______."What do you see this time? " the wise man asked."I see(8)_______ flying around high mountains, the white clouds on the mountains and the(9)_______ sky above the white clouds, " the young man answered.Then he asked the wise man's (10)_______."I feel small and powerless, " the wise man answered."A person who knows to look upward can (11)_______ understand his position(位置).When a person knows the blue sky is always overhead, he won't be so (12)_______ as to believe he rules over the world or other people."The young man felt foolish for his (13)_______.From then on , (14)_______ he began to feel as if the world owed(亏欠)him something, he looked up at the sky and remembered (15)_______ small he really was.Try to look upward when you feel too good about yourself.(1)A.busyzyC.wiseD.hard﹣working(2)A.ifB.butC.soD.or(3)A.got toB.got offC.arrived inD.got up(4)A.fatB.lightC.smallD.strong(5)A.belowB.aboveC.betweenD.against(6)A.EverythingB.anythingC.somethingD.nothing(7)A.upB.downC.outD.after(8)A.monkeys B.tigers C.chicks D.birds (9)A.redB.blueC.greenD.black (10)A.waysC.feelingsD.address (11)A.badlyB.angrilyC.hardlyD.clearly (12)A.cleverB.smartC.sillyeful (13)A.prideB.successC.luckD.smell (14)A.whateverB.wheneverC.whereverD.however (15)A.whyB.whereC.howD.what二、阅读理解(本题有15小题,每小题6分,共计30分)2.(1)Which problem is NOT mentioned in the passage?________A. Air pollution.B. Water pollution.C. Destruction of forests.D. Global warming..(2)How long will the lecture last?________A. For half an hour.B. For 80 minutesC. For an hour.D. For 120 minutes..(3)The passage is probably a(n)________?A. noticeB. poemC. diaryD. advertisement.3. When your pen is broken, you think that's the end of its life.You throw it away.It then joins tons of other garbage that is becoming a big problem in cities.Each day, about 10, 000 tons of waste is produced in Guangzhou, and 17, 000 tons of household waste is produced in Beijing.In other countries, the case is similar."If you're like most of us, most Americans, you're making seven pounds (3.17kg)of trash a day, " US writer Edward Humes told CNN.So, an American makes 102 tons of trash in a lifetime.If you simply throw away that broken pen, it goes to a landfill(垃圾填埋场)and is buried together with many other trash.To prevent polluting the groundwater, workers cover the trash with soil and keep it dry.And your pen will stay there for a long, long time, without having further use.But it could have a better destination: the recycling bin.Have you ever noticed the different colors of trash bins in the street? Many cities in China have been running a waste﹣sorting (垃圾分类)campaign.They divide trash into "recyclable waste" and "unrecyclable waste".So in Yiwu there are many "Little Yellow Dog" appearing all around the city, even in our campus.Recycling waste can save energy, reduce greenhouse gas, and keep space free for the unrecyclable trash.Take your pen as an example.At the recycling factory, its metal parts could be taken out and reused to make other things.But recycling is not enough, experts say.Making less waste in the first place is the way forward."The best thing to do is just keep using your stuff for as long as you can, " US writer Adam Minter told Time Out magazine.(1)How much trash does each American make every year on average?________A. 7 kgB. 3.17kgC. 102 tonsD. over 1 ton.(2)According to the story,how should we deal with broken pens?________A. Throw them away.B. Bury them in a landfill.C. Put them into a recycling bin.D. Give them to our friend..(3)Waste should be recycled because this can________.a.save energyb.produce greenhouse gasc.save landfill spaced.save waterA. abB. bcC. adD. ac.(4)What is the best way to reduce waste?________A. Recycle different kinds of waste.B. Keep using your things as long as you can.C. Keep waste inside your house.D. Tell people about the importance of recycling.4. Parents of very young children know this: You catch your child in the act of stealing the cookie﹣﹣the evidence of candy written on his or her face.However, you get a wide﹣eyed ________: " I didn't do it!"Learning to tell the truth, even at the risk of punishment, is an important part of moral (道德)development, and new research suggests it can take seven or more years for kids to get there.Early 2017 Professor Craig E.Smith published a study.He and his workmates chose 48 children between four and nine years of age.They told the kids a story about a boy or girl doing something wrong, such as taking a classmate's toy or candy, and then either lying about the wrong doing to a parent or confessing (承认)it.In each case, they asked the children, how would the child feel? How would the mother feel?The children's answers were generally divided according to age, which is in agreement with the stolencandy, lying and getting unpunished.They imagined the parent in the study would be angry with the child who confessed.However, the seven﹣to﹣nine﹣year﹣olds were more likely (可能的)to think the child would feel better confessing the crime and that the parent would have positive (积极的)feelings towards a confessor.Smith says, "kids of all ages who expect that a parent would feel happy about a child's confession are more likely to tell the truth rather than lie.Reward the honesty even if you feel you must punish the wrong action." He adds, what parents can learn from these studies is to listen calmly without getting angry right away when their child confesses.(1)What does the underlined word "denial" in Paragragh 1 mean?________A. 委屈B. 责备C. 否认D. 拒绝.(2)Paragragh 2 mainly tell us________.A. kids can't tell "right" from "wrong"B. it takes time for kids to learn to tell the truthC. it's wrong to punish kids for telling the truthD. all the kids are willing to confess to a bad act.(3)What did Smith and his workmates find in their study?________A. Older kids are more likely than younger children to confess to a bad act.B. Younger children are more likely than older kids to confess to a bad act.C. The four﹣to﹣five﹣year﹣olds would feel better confessing the crime.D. The seven﹣to﹣nine﹣year﹣olds thought parents would be angry with their confessions..(4)According to Professor Smith,what can parents learn from these studies?________A. Parents should at once punish the children who lied.B. Parents should tell children the wrongness of lying.C. Parents should never get angry after their children's confessions.D. Parents should show positive feeling about their children's confessions.5. I'm sure most people like music.Music can not only bring us wonderful enjoyment, but also bring us happiness when we are tired or sad.And many people have the habit of enjoying music when they are free.But to our surprise, one English school allows children to listen to music or even to have the TV on while they are studying, and they find it is helpful to improve the students' grades.According to a research at Millfield School in the UK, around 20% of teenagers work better with background music, and 10% ________when allowed to finish their work with short walks around the room while up to 80% can concentrate(集中注意)better if allowed to play with a small object.The research has made the school use a very new way, encouraging students to discover which learning styles suit them best, and then do their homework listening to music or even lying down.Some parents don't believe, but many are now accepting it at home where children are allowed to do their homework with the television on."I prefer to work on the floor with music on, " said Sam, a 13﹣year﹣old boy."At first my parent thought I didn't study hard, but my teacher asked them to look at my homework and when they saw it was OK, they agreed at last."(1)What advantage of music hasn't been mentioned in the passage?________A. Music can bring us enjoyment.B. Music can bring us happiness.C. Music can make people excited.D. Music can help to improve students' grades..(2)What does the underlined word "excel" probably mean?________A. It means "be good at doing something".B. It means "do badly in doing something".C. It means "give up doing something".D. It means "play with something"..(3)Which of the following is true?________A.B. One fifth of the students can work better with background music.C. 20% can concentrate better if allowed to play with a small object.D. No parents accept the idea..(4)What can you infer from the passage?________A. The students at Millfield School are against the new idea of allowing children to listen to music.B. More and more parents will allow children to listen to music while doing homework.C. The new idea will spread all over the world.D. More and more children will realize the importance of working hard.三、任务型阅读(本题有5小题,每小题5分,共计5分)请仔细阅读习主席给青年的建议,从A到F的六个选项中选出符合各段主题的句子,完成题.(其中一项为多余选项.)6. President Xi encouraged the country's youth to study hard and take in the knowledge like sponge(海绵).Xi has valued the development of Chinese youth.Now,let's have a look at what he has said to us.(1)_______Youth is an important time to train a person's thinking and abilities,and young people should be thirsty for knowledge and eager to learn about the new things.(2)_______Young people should have a good understanding of the history and progress of the Chinese people's hard work in modern times.They should give themselves away to the motherland,the people and the nation.(3)_______The road of life for young people is long.Along the way,there is sunshine as well as rains and winds,joy as well as sadness.(4)_______Young people should smile and never give up when facing difficulties.They should dare to dream and work very hard to realize their dreams.(5)_______Learning is necessary for young people's growth and progress.The qualities and abilities of young people will have a direct influence on realizing the Chinese Dream.试题卷Ⅱ四、词汇运用(本题有15小题,每小题1分,共计15分)A. 根据句意和括号内所给汉语注释,写出空白处各单词的正确形式(每空一词).7. Do you know the________ (意思)of the word?8. Can you________ (重复)what you said just now?I didn't hear you clearly.9. It is________ (有礼貌的)to say "Excuse me" when you ask for help.10. Mark Twain is a________ (有幽默感的)writer.11. Tom is a shy boy and he is afraid of giving________ (讲话,发言)in public.12. Chinese is________ (广泛地)spoken now by many people in the world.13. The pieces are usually cute children or________ (生气勃勃的)characters.14. Americans can hardly________(避免)buying products made in China.15. We can understand him well because of his good________ (发音).16. "It was________ (精确地)what I needed," he said.B.根据短文内容,用方框中所给单词的适当形式填空,每词限用一次。
浙江省宁波市2021年九年级上学期期中五校联考科学试题(溪口中学、尚田中学等五校)
浙江省宁波市【最新】九年级上学期期中五校联考科学试题(溪口中学、尚田中学等五校)学校:___________姓名:___________班级:___________考号:___________一、选择题1.下列实验操作正确的是()A.稀释浓硫酸B.配置食盐水C.检验装置气密性D.测定溶液pH值2.在柠檬中插入两种不同的金属可以制得水果电池。
相同条件下,水果电池的电压与两种金属的活动性差异大小有关。
下列柠檬电池的两种金属,活动性差异最大的是A.B.C.D.3.酸碱指示剂可以检测溶液的酸碱性,下列溶液能使紫色石蕊试液变蓝色的是()A.柠檬汁B.肥皂水C.白醋D.稀硫酸4.做肠胃射线透视时,要服用“钡餐”,服用后不容易被X射线透过,其主要成分是()A.BaCO3B.BaSO4C.Ba(NO3)2D.BaCl25.在学习科学的过程中,建立正确的科学观念是很重要的,下列基本科学观念所对应的叙述正确的是()A.能量观:盐酸和氢氧化钠溶液反应时温度升高,说明是吸热反应B.守恒观:化学反应前后,元素种类、原子数目均保持不变C.微粒观:二氧化硫气体是由一个硫原子、两个氧原子构成的D.分类观:生石灰、熟石灰都属于无机物中的碱类6.15%的H2O2溶液在二氧化锰催化作用下会剧烈反应产生O2。
实验室欲利用15%的H2O2溶液制取O2, 则下列装置中,仪器选择和药品放置最合理的是()A.B.C.D.7.下列各组物质中,俗名,化学名称和化学式表示的是同一种物质的是()A.烧碱、氢氧化钠、Na2OB.纯碱、氢氧化钠、NaHOC.小苏打、碳酸氢钠、NaHCO3D.熟石灰、氧化钙、CaO8.下列表中物质、用途、反应方程式和基本反应类型完全正确的是CO+CuO Cu+CO2A.A B.B C.C D.D9.下列物质在敞口容器中久置,因发生化学变化而使溶液质量减小的是()A.浓硫酸B.浓盐酸C.氢氧化钠溶液D.石灰水10.将36.5克稀盐酸和40克氢氧化钠溶液混合,充分反应,则所得溶液的pH值()A.一定等于7 B.一定大于7 C.可能等于7 D.一定小于7 11.将下列试剂分别加入KOH溶液、饱和石灰水和稀H2SO4中,能出现三种不同现象的是( )A.紫色石蕊试液B.Na2CO3溶液C.CuCl2溶液D.NaCl溶液12.在反应X+2Y=R+2M中,已知R和M的相对分子质量之比为22:9,当1.6gX与Y完全反应后,生成4.4gR,则在此反应中Y和M的质量比是()A.16:9B.23:9C.32:9D.46:913.提纯下列物质,所选用试剂及操作方法均正确的是A.A B.B C.C D.D14.(绍兴-19)下列图像不能正确反映对应变化关系的是( )A.在一定量AgNO3和Zn(NO3)2的混合溶液中加入铁粉B.向等质量的锌粉和铁粉中,分别加入相同质量分数的稀盐酸C.常温下,向硝酸钾的不饱和溶液中加入硝酸钾晶体D.向一定量的稀盐酸中加入过量的NaOH溶液15.在烧杯中盛有HCl和BaCl2溶液,向其中逐滴滴入一定溶质质量分数的碳酸钠溶液,测得溶液pH与加入的碳酸钠溶液的质量关系如图所示,则下列说法正确的是()A.A点时,加入酚酞溶液,溶液呈红色B.B点时,溶液中只含有NaClC.C点时,加入稀盐酸,有气泡产生D.A.B.C三点中,溶质的种类分别为3、2、1二、填空题16.汽车作为一种常见交通工具,已走进千家万户。
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2019-2020学年浙江省宁波市奉化区溪口中学、尚田中学等五校联考九年级(上)期中英语试卷试题卷I一、完型填空(本题有15小题,每小题15分,共计15分)阅读下面文章,掌握大意,然后从A、B、C、D四个选项中选出最佳选项.1. There was once a young man who began to feel self﹣satisfied after some small achievements.One day, the young man took a walk with a (1)_______ man from the town.On the way the young man was bragging(吹嘘)about himself, (2)_______ the wise man didn't say a word.When they (3)_______ the top, the wise man asked, "Look down.What do you see ? " "I see trees, farmland, houses and people as (4)_______ as ants working in the fields, " the young man said."What do you feel? " the wise man asked."Everything is (5)_______ me.I feel I rule the world, " the young man answered.The wise man said (6)_______.After a minute, he asked the young man to look (7)_______."What do you see this time? " the wise man asked."I see(8)_______ flying around high mountains, the white clouds on the mountains and the (9)_______ sky above the white clouds, " the young man answered.Then he asked the wise man's (10)_______."I feel small and powerless, " the wise man answered."A person who knows to look upward can (11)_______ understand his position (位置).When a person knows the blue sky is always overhead, he won't be so (12)_______ as to believe he rules over the world or other people."The young man felt foolish for his (13)_______.From then on , (14)_______ he began to feel as if the world owed(亏欠)him something, he looked up at the sky and remembered (15)_______ small he really was.Try to look upward when you feel too good about yourself.(1)A.busyzyC.wiseD.hard﹣working(2)A.ifB.butC.soD.or(3)A.got toB.got offC.arrived inD.got up(4)A.fatB.lightC.smallD.strong(5)A.belowB.aboveC.betweenD.against(6)A.EverythingB.anythingC.somethingD.nothing(7)A.upB.downC.outD.after(8)A.monkeysB.tigersC.chicksD.birds(9)A.redB.blueC.greenD.black(10)A.waysC.feelingsD.address(11)A.badlyB.angrilyC.hardlyD.clearly(12)A.cleverB.smartC.sillyeful(13)A.prideB.successC.luckD.smell(14)A.whateverB.wheneverC.whereverD.however(15)A.whyB.whereC.howD.what二、阅读理解(本题有15小题,每小题6分,共计30分)(1)Which problem is NOT mentioned in the passage?________A. Air pollution.B. Water pollution.C. Destruction of forests.D. Global warming..(2)How long will the lecture last?________A. For half an hour.B. For 80 minutesC. For an hour.D. For 120 minutes..(3)The passage is probably a(n)________?A. noticeB. poemC. diaryD. advertisement.When your pen is broken, you think that's the end of its life.You throw it away.It then joins tons of other garbage that is becoming a big problem in cities.Each day, about 10, 000 tons of waste is produced in Guangzhou, and 17, 000 tons of household waste is produced in Beijing.In other countries, the case is similar."If you're like most of us, most Americans, you're making seven pounds (3.17kg)of trash a day, " US writer Edward Humes told CNN.So, an American makes 102 tons of trash in a lifetime.If you simply throw away that broken pen, it goes to a landfill(垃圾填埋场)and is buried together with many other trash.To prevent polluting the groundwater, workers cover the trashwith soil and keep it dry.And your pen will stay there for a long, long time, without having further use.But it could have a better destination: the recycling bin.Have you ever noticed the different colors of trash bins in the street? Many cities in China have been running a waste﹣sorting (垃圾分类)campaign.They divide trash into "recyclable waste" and "unrecyclable waste".So in Yiwu there are many "Little Yellow Dog" appearing all around the city, even in our campus.Recycling waste can save energy, reduce greenhouse gas, and keep space free for the unrecyclable trash.Take your pen as an example.At the recycling factory, its metal parts could be taken out and reused to make other things.But recycling is not enough, experts say.Making less waste in the first place is the way forward."The best thing to do is just keep using your stuff for as long as you can, " US writer Adam Minter told Time Out magazine.(1)How much trash does each American make every year on average?________A. 7 kgB. 3.17kgC. 102 tonsD. over 1 ton.(2)According to the story,how should we deal with broken pens?________A. Throw them away.B. Bury them in a landfill.C. Put them into a recycling bin.D. Give them to our friend..(3)Waste should be recycled because this can________.a.save energyb.produce greenhouse gasc.save landfill spaced.save waterA. abB. bcC. adD. ac.(4)What is the best way to reduce waste?________A. Recycle different kinds of waste.B. Keep using your things as long as you can.C. Keep waste inside your house.D. Tell people about the importance of recycling.Parents of very young children know this: You catch your child in the act of stealing the cookie﹣﹣the evidence of candy written on his or her face.However, you get a wide﹣eyed ________: " I didn't do it!"Learning to tell the truth, even at the risk of punishment, is an important part of moral (道德)development, and new research suggests it can take seven or more years for kids to get there.Early 2017 Professor Craig E.Smith published a study.He and his workmates chose 48 children between four and nine years of age.They told the kids a story about a boy or girl doing something wrong, such as taking a classmate's toy or candy, and then either lying about the wrong doing to a parent or confessing (承认)it.In each case, they asked the children, how would the child feel? How would the mother feel?The children's answers were generally divided according to age, which is in agreement with the stolen candy, lying and getting unpunished.They imagined the parent in the study would be angry with the child who confessed.However, the seven﹣to﹣nine﹣year﹣olds were more likely (可能的)to think the child would feel better confessing the crime and that the parent would have positive (积极的)feelings towards a confessor.Smith says, "kids of all ages who expect that a parent would feel happy about a child's confession are more likely to tell the truth rather than lie.Reward the honesty even if you feel you must punish the wrong action." He adds, what parents can learn from these studies is to listen calmly without getting angry right away when their child confesses.(1)What does the underlined word "denial" in Paragragh 1 mean?________A. 委屈B. 责备C. 否认D. 拒绝.(2)Paragragh 2 mainly tell us________.A. kids can't tell "right" from "wrong"B. it takes time for kids to learn to tell the truthC. it's wrong to punish kids for telling the truthD. all the kids are willing to confess to a bad act.(3)What did Smith and his workmates find in their study?________A. Older kids are more likely than younger children to confess to a bad act.B. Younger children are more likely than older kids to confess to a bad act.C. The four﹣to﹣five﹣year﹣olds would feel better confessing the crime.D. The seven﹣to﹣nine﹣year﹣olds thought parents would be angry with their confessions..(4)According to Professor Smith,what can parents learn from these studies?________A. Parents should at once punish the children who lied.B. Parents should tell children the wrongness of lying.C. Parents should never get angry after their children's confessions.D. Parents should show positive feeling about their children's confessions.I'm sure most people like music.Music can not only bring us wonderful enjoyment, but also bring us happiness when we are tired or sad.And many people have the habit of enjoying music when they are free.But to our surprise, one English school allows children to listen to music or even to have the TV on while they are studying, and they find it is helpful to improve the students' grades.According to a research at Millfield School in the UK, around 20% of teenagers work better with background music, and 10% ________when allowed to finish their work with short walks around the room while up to 80% can concentrate(集中注意)better if allowed to play with a small object.The research has made the school use a very new way, encouraging students to discover which learning styles suit them best, and then do their homework listening to music or even lying down.Some parents don't believe, but many are now accepting it at home where children are allowed to do their homework with the television on."I prefer to work on the floor with music on, " said Sam, a 13﹣year﹣old boy."At first my parent thought I didn't study hard, but my teacher asked them to look at my homework and when they saw it was OK, they agreed at last."(1)What advantage of music hasn't been mentioned in the passage?________A. Music can bring us enjoyment.B. Music can bring us happiness.C. Music can make people excited.D. Music can help to improve students' grades..(2)What does the underlined word "excel" probably mean?________A. It means "be good at doing something".B. It means "do badly in doing something".C. It means "give up doing something".D. It means "play with something"..(3)Which of the following is true?________A.B. One fifth of the students can work better with background music.C. 20% can concentrate better if allowed to play with a small object.D. No parents accept the idea..(4)What can you infer from the passage?________A. The students at Millfield School are against the new idea of allowing children to listen to music.B. More and more parents will allow children to listen to music while doing homework.C. The new idea will spread all over the world.D. More and more children will realize the importance of working hard.三、任务型阅读(本题有5小题,每小题5分,共计5分)请仔细阅读习主席给青年的建议,从A到F的六个选项中选出符合各段主题的句子,完成题.(其中一项为多余选项.)President Xi encouraged the country's youth to study hard and take in the knowledge like sponge(海绵).Xi has valued the development of Chinese youth.Now,let's have a look at what he has said to us.(1)_______Youth is an important time to train a person's thinking and abilities,and young people should be thirsty for knowledge and eager to learn about the new things.(2)_______Young people should have a good understanding of the history and progress of the Chinese people's hard work in modern times.They should give themselves away to the motherland,the people and the nation.(3)_______The road of life for young people is long.Along the way,there is sunshine as well as rains and winds,joy as well as sadness.(4)_______Young people should smile and never give up when facing difficulties.They should dare to dream and work very hard to realize their dreams.(5)_______Learning is necessary for young people's growth and progress.The qualities and abilities of young people will have a direct influence on realizing the Chinese Dream.试题卷Ⅱ四、词汇运用(本题有15小题,每小题1分,共计15分)A. 根据句意和括号内所给汉语注释,写出空白处各单词的正确形式(每空一词).Do you know the________ (意思)of the word?Can you________ (重复)what you said just now?I didn't hear you clearly.It is________ (有礼貌的)to say "Excuse me" when you ask for help.Mark Twain is a________ (有幽默感的)writer.Tom is a shy boy and he is afraid of giving________ (讲话,发言)in public.Chinese is________ (广泛地)spoken now by many people in the world.The pieces are usually cute children or________ (生气勃勃的)characters.Americans can hardly________(避免)buying products made in China.We can understand him well because of his good________ (发音)."It was________ (精确地)what I needed," he said.B.根据短文内容,用方框中所给单词的适当形式填空,每词限用一次。