2015.2期末考试试题(附加类似题)

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2015学年度八年级语文第二学期期末检测卷及答案

2015学年度八年级语文第二学期期末检测卷及答案

2014~2015学年度第二学期期末教学质量检测试卷八年级语文一、基础知识与能力考查(共24分)1.下列词语中加点字的读音完全正确的一项是()(2分)A.睥.睨(pì)啮.齿(niâ)缄.默(jiān)脂粉奁.(lián)B.家醅.(pēi)吞噬.(shì)博识.(zhì)文绉绉..(zhōu)C.真谛.(dì)胆怯.(qiâ)鬈.发(juǎn)颔.首低眉(hàn)D.酬和.(hâ)招徕.(lái)哂.笑(shěn)即物起兴.(xīng)2.下列词语中,没有错别字的一项是()(2分)A. 叱咤风云谈笑风生消声匿迹戛然而止B. 张慌失措周道如砥本色当行任劳任怨C. 重蹈复辙精神矍烁孜孜不倦妙手回春D. 风声鹤唳莫衷一是脍炙人口风雪载途3.下列句子中加点的词语使用有误的一项是()(2分)A.他生活底子厚实,知识渊博,写起文章来一挥而就....。

B.他是学校的长跑冠军,但与专业的短跑运动员相比,还是显得相形见绌....。

C.目前我国农村家庭普通本科毕业生失业率已高达30.5%,为了中国农村的发展,请某些用人单位摘掉有色眼镜,一视同仁....,给来自农村的学子一个公平竞争的机会!D.用意大利的方式击败意大利,用乌拉圭的方式击败乌拉圭,哥斯达黎加队从有三支世界冠军队的死亡之组脱颖而出,成为世界杯历史上的史诗级黑马,还真令人有鹤立鸡群....的感觉!4.下列句子中没有语病的一项是( ) (2分)A. 4月7日我国著名的田径运动员刘翔通过个人微博,发布题为“我的跑道,我的栏”,正式宣布退役。

B. 是否选择对社会对未来负责的低碳生活方式,是衡量现代人良好文明素质的重要标准。

C. 他的画作风格清新,色彩丰富,色调和谐,得到画界及评论界的一致好评。

D. 通过使用“电子往来港澳通行证”自助通关,使旅客大大缩短了排队等候过关的时间。

2015第二学期八年级物理期末试卷及答案

2015第二学期八年级物理期末试卷及答案

12014—2015学年度第二学期期末检测卷八年级物理试卷一、填空题(每空2分,计30分) 1. 学校每周都要举行升旗仪式,你知道吗?国旗旗杆顶端安装的是_______滑轮,它的作用是____________。

2. 近年来,合肥地区也时有雾霾天气,雾霾的主要成分是PM2.5(直径不大于2.5微米的颗粒物),它们在空中做无规则运动,很难自然沉降地面,吸入后会进入血液对人体形成危害。

PM2.5在空中的运动_______ (选填“属于”或“不属于”)分子的运动。

3. 意大利科学家____________最早通过实验测出大气压的数值,一个标准大气压等于____________Pa 。

4. 生活和生产中的很多物品都运用了物理学知识。

图(a )所示为紫砂茶壶,壶嘴和壶身构成一个________;图(b )所示为注射器,用它抽取药液时应用了_____________的知识。

5. 小明站在地面上准备用一个滑轮组将重物提升到二楼,如图,请在图中画出绕线方法。

6. 掷出的铅球在水平方向能继续前进,是因为_________,铅球最终要落到地面。

是因为铅球受到_______的作用。

7. 有一潜水艇悬浮在水中,当用压缩气体把水舱中的水排出一部分时,潜水艇将________(选填“上浮”或“下沉”),在未露出水面之前,潜水艇所受的浮力将________(选填“变大”、“变小”或“不变”)。

8. 一金属块在空气中受到的重力为39N ,把它全部浸没在水中称时(金属块未接触地面)弹簧测力计读数为34N ,则该金属块受到水对它的浮力为____N ,该金属块的体积为_______m 3。

(g 取10N/kg ,ρ水=1.0×103kg/m 3) 9. 如图所示杠杆,O 是支点,中间挂一重物G ,如果在杠杆的另一端①处加一个力F 使杠杆平衡,且要求所加的力要最小,则这个力应沿_______方向。

二、选择题(每小题3分,计30分;将每小题中符合题意的一个选项序号填写在对应的题号下面)10.在体育考试中,小明投出的实心球在空中的运动轨迹如图所示。

2014~2015学年度第二学期期末考试试卷八年级物理

2014~2015学年度第二学期期末考试试卷八年级物理

2014~2015学年度第二学期期末考试试卷八年级物理注意事项考生在答题前请认真阅读本注意事项:1.本卷共6页,满分为100分,考试时间为100分钟.考试结束后,请将本试卷的答题卡交回.2.答题前,请务必将自己的姓名、考试证号用0.5毫米黑色字迹的签字笔填写在答题卡上指定的位置.本试卷统一取g=10N/kg第I卷(选择题共24分)一、选择题:(12小题,每小题2分,共24分)每小题给出的四个选项中只有一个选项正确.请将正确的答案按要求填涂在答题卡上.1.体温计示数升高时,关于体温计内的水银,下列物理量不变的是:A.体积B.质量C.密度D.温度2.关于粒子和宇宙,下列说法中正确的是A.分子是微观世界中的最小微粒B.毛皮与橡胶棒摩擦后能吸引轻小物体是摩擦创造了电荷C.原子结构与太阳系十分相似,它的中心是原子核D.电子的发现揭示了原子核是有结构的3.如图所示的事例中,属于减小压强的是A.用厚纸垫手B.用刀切芒果C.用线切蛋D.用针绣花4.使用如图所示的装置来提升物体时,既能省力又能改变力的方向的装置是5.日常生活中采取的措施,利用惯性的是A.锤子的木柄撞击硬地面套紧锤头B.禁止汽车超载行驶C.公交车启动提醒乘客抓好扶手D.驾驶前系好安全带6.下列关于运动与力的说法正确的是A.在平衡力作用下,物体一定处于静止状态B.如果要使一个物体持续运动,就必须对它施加力的作用C.力的三要素完全相同的两个力,一定是一对平衡力D.物体不受力的作用,运动状态就一定不改变7.教室的门关不紧,常被风吹开.小明在门与门框之间塞入硬纸片后,门就不易被风吹开了.下列解释合理的是A.门被风吹开是因为门没有受到摩擦力的作用B.门没被吹开是因为风吹门的力小于摩擦力C.塞入硬纸片是通过增大压力来增大摩擦D.塞硬纸片是通过减小接触面的粗糙程度来减小摩擦8.对下列情景涉及的物理知识,描述正确的是A.建筑工人砌墙时,利用重垂线可以把墙砌直,因为重力的方向总是竖直向下的B.课本静止放在水平桌面上,课本对桌面的压力与桌面对它的支持力是一对平衡力C.向墙上按图钉时,手对图钉帽产生的压强等于图钉尖对墙壁产生的压强D.给正在运动的小车再施加一个力,小车就会比原来运动得更快9.在研究液体压强的实验中,进行了如图所示的操作,有关操作与结论正确的是A .要使实验现象明显一些,U 型管内液体的密度应适当大一些B .甲、丙两图的操作可探究液体内部压强与液体深度的关系C .对比丙、丁两图可得液体内部压强与盛液体的容器形状有关D .选用乙、丙两图的操作来探究液体内部压强与液体密度的关系 10、小聪和小明为了探究“温度和物质状态对同种物质密度的影响.在一定的环境下将lg的冰加热,分别记录其温度和体积的数据,利用描点法得到了如图所示的图象.则下列说法中正确的是 ( ▲ )A .小明和小聪的研究结果表明:密度是不会随状态而发生改变的B .当水从0℃上升到4℃的过程中,其密度逐渐增大C .在0℃时,冰块的密度比水大D .当0℃时,在冰变成水的过程中质量变大10.在中考体育“引体向上”的测试中,甲、乙两生的手臂长相同,质量之比是9:8,甲在1min 内完成5个,乙在80秒内完成6个,则甲乙两人克服重力做功的功率之比是:A .9∶8B .5∶4C .4∶5D .5∶611.两容器分别装有甲、乙两种液体,密度分别为第9题图甲 乙 丙 丁甲、乙,现有A、B两个实心小球,质量分别为m A、m B,体积分别为V A、V B,密度分别为、A。

2015二中八下期末卷

2015二中八下期末卷

二中广雅八下期末试卷二.单项选择26. I know a little bit about Italy as my wife and I ____ there several years ago.A. are goingB. had beenC. wentD. have been27. ---Mr. Li will check our home work this afternoon. ____ you ___ it?--- Not yet. I’ m doing it right now.A.Have, finishedB. Did, finishC. will, finishD. Do, finish28. ---What a day! It’s raining again. I’m afraid we can’t go hiking tomorrow.--- Don’t worry. It won’t ____ lon g.stB. rainC. dropD. fall29. --- I just can’t stop worrying about the result of my English test。

-- -———. There’s nothing you can do now but wait.A. RelaxB. Go aheadC. Go for itD. God luck30. They have decided to ___ the job to Mary.A. provideB. offerC. applyD. get31. –May I stop my car here?--- No, you____.A.May notB. mustn’tC. needn’tD. don’t have to32. Police have ___ all hope finding the two drivers alive.A. given inB. given upC. given outD. given away33. The city police ___ roadblocks to check passing vehicles.A. set offB. set upC. set outD. set about34. We’ve made good predictions and are sure to ___ the match.A. beatB. winC. hitD. succeed35. We got the news that a ship carrying 458 people sank in the river with a ____ heart.A. sadB. blueC. heavyD. terrible36. In the TV show ―Tiger Mom Cat Dad‖, we all share and voice their different opinions of the way to____ kids.A. teachB. raiseC. trainD. rise37. – Our school bus will leav e at 8 o’clock tomorrow. Don’t be late.-- OK. I’ll be there ten minutes ___.A. soonerB. slowerC. fasterD. earlier38. They are able to talk openly to one anther whenever ____ of them feels hurt.A. eitherB. bothC. someD. all39.--- What on earth do you want?-- I didn’t ____ the cap ,but the cup.A. askB. meanC. sayD. like40. --- Could you help looks after the homeless kids with less pay?--- With pleasure. I never mind ___.A.What will I do for themB.Why I stay with themC.When will I play with themD.How much I will be paid三、完形填空It Seemed Like a Good Idea at the TimeI really only meant it as a joke. I wasn't trying to steal anything honestly.My friend Matthew started bringing his new cell phone to class last week. He was walking around bragging (吹嘘) about it to everyone. He was saying, "My cell phone can download the newest 41 off the internet." Then he 42 everyone by downloading a game and starting to play it. The pictures and sound were really 43.After class, he would use his cell phone to watch TV. The 44of us didn't have a phone like 45 , so we had to crowd around him. I was just trying to see the screen, but there were so many other kids 46I could not see it clearly. I was getting really jealous.But then yesterday, he forgot his cell phone at the end of class. He left it right on hisdesk. 47 noticed it was there except me. I decided to teach him a lesson. I took his phone quietly off the desk, and put it in my own bag. My 48 was to give it back to him the next day. I just wanted to see his49 . Maybe he would stop 50 such a show-off.But this morning he rushed into class, screaming and yelling (吼叫). He was very 51 and almost mad. He started accusing (指责) different people of 52 his phone, but I had it in my 53 the whole time. He even started 54 with another classmate because Matthew was sure that person had taken it. The teacher sent them to the headmaster's office. They 55 got in a lot of trouble. Now I don't know whatto do! If I tell him that I took the cell phone, he'll think I stole it. If I don't tell him, then I really did steal it. How did I get into such a trouble?( )41. A. ads ( )42. A. gave ( )43. A. good ( )44. A. other ( )45. A. hers ( )46. A. and ( )47. A. Everybody ( )48. A. plan ( )49. A. reaction ( )50. A. to be ( )51. A. happy ( )52. A. losing ( )53. A. desk ( )54. A. beating ( )55. A. both B. songsB. showedB. badB. anotherB. oursB. butB. SomebodyB. suggestionB. answerB. beingB. quietB. stealingB. handB. fightingB. allC. filmsC. lentC. noisyC. restC. hisC. thenC. AnybodyC. dreamC. replyC. gettingC. sadC. playingC. bagC. defeatingC. neitherD. gamesD. askedD. unclearD. restsD. theirsD. thatD. NobodyD. actionD. behaviorD. to getD. angryD. usingD. pocketD. chattingD. none四、阅读理解A.56. We can read the above material mainly ____.A. on TVB. in the newspaperC. in a school reportD. in the guitar facto57. From the reading we know the shop____.A. only sells guitarB. only sells parts of guitarC. also has lessons about musicD. can’t help to repair guitars58. The reading doesn’t tell us_____.A. the address of the shopB. the name of the shopC. the phone number of the shopD. the price of the guitar59. If you want to know some information about the shop, you can____.A. call 604-525-8152B. got to 829-12 ST(Kingsway), New WestminsterC. visit their websiteD. send them am email60. In this shop, you can do thing expect _____.A.getting your guitar repairedB. taking a drum classC. learning something about singingD. buying a piano for yourselfBWhen my son, Mark, was in the third grade, he saved all his pocket money for over three months to buyholiday presents. The third Saturday in December Mark said he had made his list and had twenty dollars in hispocket.I drove him to a nearby supermarket. Mark picked up a hand basket and went in while I waited and watched in the car. It took Mark over 45 minutes to choose his presents. Finally he came to the checkout counter (交款处) and reached into his pocket for his money. It was not there! There was a hole in his pocket, but no money. Mark stood there holding his basket, tears falling down his face.Then a surprising thing happened. A woman came up to Mark and took him in her arms."You would help me a lot if you let me pay for you," said the woman."It would be the most wonderful gift you could give me. I only ask that one day you will pass it on. When you grow up, I would like you to find someone you can help.When you help others, I know you will feel as good about it as I do now."Mark took the money, dried his tears and ran back to the checkout counter as fast as he could. That yearwe all enjoyed our gifts almost as much as Mark enjoyed giving them to us.I would like to say "thank you" to that very kind woman, and tell her that four years later, Mark went houseto house collecting blankets (毯子) and clothes for the homeless people in the fire. And I want to promise her that Mark will never forget to keep passing it on.61. From the reading we can learn the story probably happen ____________.A. on Christmas Day B after New Year’s DayC. before Christmas Day D on New Year’s Day62. When they got to the supermarket, Mark went in____________.A. with the writerB. by himselfC. with the womanD. with his friends63. What happened to Mark in the supermarket?A. His gifts were stolen.B. He broke his basket.C. He lost his money.D. He lost his way.64. Why did the writer want to say "thank you" to the woman?A. Because she bought Mark a nice present.B. Because she always paid money for others.C. Because she taught Mark to help people in need.D. Because she collected clothes for the homeless.65. The best title for the reading is____________.A. A Big SupermarketB. A kind WomanC. A Happy FamilyD. A Wonderful GiftCWhen I was a child, my parents often took me to an old house in a thick forest. No other children ever stayed there.I didn’t even have the choice of playing with a brother or sister.I could never understand what the attraction(吸引) of the house was, even for my parents, who enjoyed nothing better than to sit in silence with a good book. The woman in the house, my father’s distant cousin, was a terrible cook and her food was inedible.One day, when I was wandering around the garden behind the house, I noticed a wooden house which had clearly been abandoned(被遗弃的). As I walked towards it, I heard a noise, like an animal moving hurriedly away. Then I saw a man with a long beard standing at the door. I was greatly surprised.―Please don’t tell them you saw me,‖ he said. ―They never use this place, and I have nowhere else to live.‖―Don’t worry,‖ I said. ―I won’t tell anyone. But are you all right out here? I mean—do you have enough to eat?‖ The old man shook his head.The same evening, I took a small plastic bag into the dining room and, while no one was looking, emptied some of the food into it. Later, I got out of the back door secretly and gave the food to the old man, whose name I had discovered was Taff.I had neve r seen anything else as lovely as the smile of satisfaction on Taff’s face when he ate the food. From then on, my visits to the old house had a purpose, and I enjoyed every minute of the rest of my stay.66. How did the writer feel about staying in the old house at first?A. He was happy to be with his parentsB. He enjoyed reading good books thereC. He was pleased with the woodsD. He felt very lonely67. The underlined word ―inedible‖ is closest in meaning to ―___________‖A. too bad for him to eatB. nice to look atC. not enough to eatD. as delicious as usual68. The writer discovered the old man _________ the old houseA. near the back door ofB. in the dining room ofC. in the garden behindD. among the bushes before69. What can we know about the old man from the passage?A. He was poor and hungryB. He helped to repair the old houseC. He liked to play hide-and-seek with the writerD. He raised many animals70. The story mainly tells us ________A. it’s nice to raise wild animalsB. it’s good to live in the forestC. it’s valuable to help othersD. it’s comfortable to live in the old house72. This is because the island is so _______ to the equator.73. I learned about the inventions that _______ to color movies, too.74. When Sarah was a teenager, she ______ to fight over almost everything with her family.75. Even more serious difficulties include ________ weather conditions and heavy storms.Key:71.cleared 72. close 73. led 74. used 75. freezing六.阅读理解填词A man was really worried about his son, who was sixteen years old but had no courage at all. So he d___76____ to call on a Buddhist monk(和尚) to train his child.The monk said to him, "You should leave your son a___77____ here. I'll make him into a real man within three m___78____. However, you can come to see him during this period. "The boy's father r___79___ after a long time. The monk arranged a boxing m___80____ between the child and an experienced boxer. Each time the fighter struck the boy, he f____81____ down, and he stood up again; and each time a punch knocked him down, the boy stood up again. S____82____ times later, the Buddhist monk asked, "What do you think of your child?""What a shame!" the boy's father said. "I never thought he would be so easily knocked down. I needn't have him here any l___83____.""I'm sorry that that's all you see. Don't you see that each time he falls down; he stands up again i___84____ of crying? That's the courage.‖If each time you are knocked down, you have the courage to stand up again. That’s the r___85___ courage.Key:76. decided 77. alone 78. months 79. returned 80. match81. fell 82. Several 83. longer 84. instead 85. real七.书面表达你的英文名叫Amy,向大家介绍你自己,要点如下:1.今年14岁,是武汉二中八年级的学生2.你乐于助人,在家经常帮助父母做家务,在校时同学有困难也主动帮忙,曾在敬老院当过志愿者3.你勇敢独立,去年独自参加了去北京的夏令营,学到很多关于中国历史的知识,你梦想有一天能攀登世界上最高的山峰,为实现梦想永不言弃。

2014—2015学年度第二学期期末考试

2014—2015学年度第二学期期末考试

2014—2015学年度第二学期期末考试五年级数学试题(时间:90分钟)等级:一、认真思考,填一填。

1.如果电梯上升15层记作+15,那么它下降2层应记作()。

2.把5米长的木料平均截成8段,每段占这根木料的()(),每段长()米。

3.23 =()÷()=()15 5÷8=()()=30()4.用分数表示下面各图中的阴影部分。

5.在里填上“>”、“<”或“=”。

59 58 53 35 78 91013 0.33 2.25 214 0.83 566.在括号里填上合适的容积或体积单位。

一个热水瓶的容积约是2()。

一间教室的体积约是144()。

一本词典的体积大约是900()。

一个墨水瓶的容积约是60()。

7.用棱长1厘米的小正方体木块拼成一个正方体模型,至少要用()块小正方体木块,这个正方体模型的表面积是()平方厘米,体积是()立方厘米。

8.一个长方体的底面积是18平方厘米,体积是45立方厘米。

它的高是()厘米。

9.从第1盒中任意摸出一个球,摸出白球的可能性是(),从第2盒中任意摸出一个球,摸出白球的可能性是()。

二、火眼金睛,判一判。

1.0既不是正数也不是负数。

()2.北偏东30°,也可以说成东偏北30°。

()3.真分数都小于1,假分数都大于1。

()4.如果甲、乙两数的最大公因数是1,那么这两个数的最小公倍数就是它们的积。

()5.长方体有12条棱,8个顶点,6个面,相对面的面积相等。

()三、开动脑筋,选一选。

1.某一天白天的最高气温是9℃,夜晚最低气温-3℃。

白天和夜晚气温相差()℃。

A.6 B.12 C.-122.分子与分母相差1的分数一定是()。

A.真分数B.假分数C.最简分数3.如果a=2×3×5,b=2×2×3,那么a和b的最大公因数和最小公倍数分别是()。

A.4和60 B.6和60 C.6和3604.右面的两个长方体是由一样的小正方体拼成的,这两个长方体()。

2015年初二英语下册期末试卷(含答案)

2015年初二英语下册期末试卷(含答案)

2015年初二英语下册期末试卷(含答案)2014-2015学年度第二学期期末教学质量检测试卷八年级英语(总分:100分时间:100分钟)题号第I卷第II卷总分得分第I卷(共60分)I、单项选择。

(每小题1分,共15分)()1.She lives in a house,but she never feels . A. alone,lonelyB. lonely,aloneC. alone, aloneD. lonely, lonely ()2. I forgot to take the map. So I had difficulty ______the way. We had to ask the policeman for help. A. find B. to find C. finding D. found ()3.We will go climbing as soon as the rain ________.A. stopsB. will stopC. is stoppingD. stopped ()4.―MayI ________ your CD player? ―Sure. But y ou can only _____it fora week. A. borrow; keep B. borrow; lend C. lend; keep D. keep; borrow ()5.I met a good friend of mine while I _____ on the street. A. walks B. walk C. was walking D. an walking ()6. ―Dear students, please read every sentence carefully. ― _________you are, ______mistakes you’ll make. A. The more carefully; the fewer B. The more careful; the less C. The more carefully; the less D. The more careful; the fewer ()7.We didn’t learn __________in this lesson. A. something new B. new something C. anything new D. new anything ()8.I haven’t decided when _____ a holiday yet. A. took B. taking C. to take D. take ()9.Tom ______the USA. He ________back in two months.A. has gone to; comesB. has gone to; will beC. has been to; comesD. has been to; will be ()10.―They didn’t go to the park yesterday. ―___________. A. So we did B. So did we C. Neither we did D. Neither did we ()11.She finds _______hard to finish the work on time. She only has five minutes left. A. that B. this C. it D. its ()12.He eats ________food, so he is _____fat. A. much too; too much B. much too; many too C. too much; much too D. too much; many too ()13.―Is this your book?―No, it is ______book. It belongs to_______. A. his;his B. his; him C. him; his D. him; him ()14.She used to ______ in the morning, but now she is used to ________ at night. A. read; read B. read; reading C. reading; read D. reading; reading ()15.He ______ much food _____the poor family during the hard time. A. provided; to B. offered; with C. provided; with D. provided; for Ⅱ、完形填空。

2015年八年级第二学期期末测试题

2015年八年级第二学期期末测试题

2014—2015年度第二学期八年级期末测评物理试卷一:填空题(第1—8题每空1分,第9—11题每空2分,共26分)1.物理学中,常用新的物理量对不同事物进行比较,比如要比较物体运动的快慢,需要引入速度;要比较做功的快慢.......,需要引.....,需要引入;要比较压力的作用效果入。

2.跳伞运动员在空中匀速下降....的过程中,运动员的动能 (选填“变大”、“变小”或“不变”),重力势能 (选填“变大”、“变小”或“不变”)。

3.如图船闸中,仅阀门A 打开,上游和闸室组成 ,拦河大坝修成“上窄下宽”的形状是因为液体的压强随深度..的增加而(选填“增大”、“减小”或“不变”).第3题图第4题图第5题图4.草坪式浴室防滑垫的正反面如图所示,其正面做成仿草坪式,目的是为了增大;反面的许多小吸盘在作用下,使垫紧贴在地面上,从而达到防滑效果.5.如图所示,底面积和质量都相同....的不同液体,放在水平桌.........的A、B两容器,装有质量相同面上,液面相平....,则液体对容器底部的压强P A P B(选填“大于”“等于”“小于”),容器对桌面的压强P A′P B′(选填“大于”“等于”“小于”).6. 如图所示,用两个完全相同的滑轮,匀速提升质量相等的物体.......。

且物体质量大于滑轮质量,不计绳重和摩擦。

比较甲、乙两种使用方式可知更省力,机械效率更高 (均选填“甲”或“乙”)。

7.刘佳的妈妈从超市买回来一袋胡萝卜,刘佳挑选了一个最大的用细线系好挂在弹簧测力计上,如图所示,可知胡萝卜重为 N,如果在系线处....将胡萝卜切成两段,则G A_______G B(选填“大于”、“小于”或“等于”)第6题图第7题图8. 木块的密度是O.6×103kg/m3,冰块的密度是O.9×103kg/m3,若它们质量相等....,都漂浮在水面上,则木块受到的浮力冰块受到浮力。

若把质量相等....的实心木块和实心铁块,放入水中静止..后,木块受到浮力铁块受到的浮力(选填“大于”、“等于”或“小于”)。

2015学年第二学期期末学业考试试卷.docx

2015学年第二学期期末学业考试试卷.docx

2015学年第二学期期末学业考试试卷七年级科学温馨提示:1.本卷满分100分,考试时间90分钟。

2. 本卷共6页,四大题,37小题。

3. 答题时,请把答案写在答题卷对应的位置上,直接做在试卷上无效。

试卷I-、伦择題(本15 纟题2分,想30分。

镐遑出各题申一个符合题盍的比廉俚观,不 遑、多(i 、他不令分)1.著名作家海伦•凯勒失去了听觉和视觉,但她通过“阅读”盲文学习了人量的知识,她获取信息 的主要手段是() A. 触觉 B.味觉 C.嗅觉 D.心灵感应5. 人站在匀速上升的电梯上,下列哪一对是平衡力? ( )C.电梯的重力与电梯对人的支持力D.电梯的重力与电梯对地球的吸引 6.从“国际劳动节”到“六一儿童节”,太阳直射点在地表的位置及移动方向是()A.位于北半球,并向北移动B.位于南半球,并向南移动A. ①是嫁接,是营养繁殖 C.③中种子萌发最先长出的是胚芽3. 地球自转产生的地理现象是() A. 昼夜长短的变化 B.昼夜更替4. 听觉的形成是在() A.耳蜗 B.鼓室 B. ②是组织培养,植物繁殖的速度很快D.①②是无性生殖,③是有性生殖 C. 正午太阳高度的变化 D.四季的变化 C.人脑皮层的听觉屮枢 D.前庭和半规管A.人的重力与电梯对人的支持力B.人对电梯的压力与电梯对人的支持力2.下列有关植物生殖方式的叙述屮,不正确的是(C.位于北半球,并向南移动D.位于南半球,并向北移动7. 某天晚上,小金在天空屮看见一•轮满月。

此时日、地、月三者的相对位置图正确的是(8. 以下是我们在生活屮可见到的几种现彖:①用力揉血团,血团形状发生变化;②篮球撞击在篮板上被弹冋;③用力握小皮球,球变瘪了;④一阵风把地血上的灰尘吹得漫天飞舞。

在这些现象 中,物体因为受力而改变运动状态的是 () A. B.②③ C.③④ D.②④9. 在站台前有甲、乙两列原来静I 上的火车,突然坐在乙车上的乘客发现站台和甲车都在以相同速度运动,那么,他选择的参照物是() A.甲车B.乙车C. 10.下列说法中正确的是( ) A.光的传播速度总是3.0X108 m/sC.光的传播不需借助媒介11・人的受精卵形成、受精卵开始分裂以及胚胎发育的场所分别是()A.卵巢、输卵管、子宫B.输卵管、输卵管、子宫C.输卵管、子宫、子宫D.输卵管、子宫、阴道 12. 若小球在运动过程中只受到力F 的作用,且运动过程屮力F 始终保持不变,则小球的运动轨迹(用虚线表示)不可能的是( )13. 在红色碧桃砧木上嫁接门色碧桃,嫁接枝条上的花色将是( )A.红色:粉红:口色=1: 2: 1B.红白色各半C.全红色D.全门色 14. 关于运动和力的关系,下列说法屮正确的是()A. 只要有力作用在物体上,物体就能运动B. 只要有力作用在物体上,物体的运动状态一定发生变化C. 只要物体的运动状态发生改变,就一定有力作用在物体上D. 只要物体在运动,就一-定有力作用在物体上 15. 如图所示,粗细均匀的圆柱体AB 放置在凸透镜的主光轴上,卩为2倍焦距点,圆柱体所成像的形状和位置应是( )A.两头细屮间粗,像到镜距离都大于焦距A 冨,A 「站台 D.无法判断 B ・光总是沿玄线传播的D.明亮的月光是光源 ABP F 卄F P扬声滦发声时小咸片上下眺仍图15 的重要发明,远在商周时代就用编钟演奏了。

2015学年二中八年级上英语期末考试试卷及答案

2015学年二中八年级上英语期末考试试卷及答案

武汉二中八年级上学期期末考试英语试卷时间:100分钟分数:100分一、听力部分(20分)笔试部分二、单项选择(每小题1分,共20分)1. —Jim,I want to be __________ engineer when I grow up.—Sounds fantastic.A. aB. anC. theD. /2. —Did your parents go to climb Mount. Tai last Sunday?—No, they _______went to a movie.A. bothB. allC. eitherD. each3. — We can’t pass the exam, ______ we study hardA. becauseB. unlessC. thoughD.or4. —I don’t know how to be good with my family problem.—Could you give me some ______ .A. adviceB. messagesC. informationD. invitation5. —My mother says my friend is similar ______me,but l think she is different ______me.A. to:fromB. as:fromC. to:toD. as:to6. My brother is as as me. We both like telling jokes.A. outgoingB. more outgoingC. most outgoingD. very outgoing7. We must work hard. There _______an important exam in June.A. will haveB.is going to haveC.will beD.has8. —______people came to Baotu Spring during May 1stA. hundredB. hundred ofC. hundred s ofD. Ten hundreds9. — Can you stay here longer?—_______.But I have to prepare for my exam.A. I’d love to.B. I’m afraid not.C. I’m sorry, I can’t.D. No. I’m not available10. I want to go ________ for my winter vacation.A. somewhere differentB. different somewhereC. anywhere differentD. different anywhere11.—_______ lovely day! Let’s go for a walk.A. What aB. How aC. HowD. What an12. Please _________ the light when you leave the classroom.A. turn onB. turn offC. turn downD. turn on13.—Spring Park is the place in the city on weekends. Lots of people enjoy doingdifferent kinds of activities there.A. worstB. most terribleC. quietestD. most popular14.—are you going to do that?—I am going to take acting lessons.A. WhenB. HowC. WhereD. What15.—Mary will go to Sydney if she a five-day trip.A. haveB. hadC. will haveD. has16.—What do you think of China’s Got Talent.—________.They are so boringA. I like it very much.B. I can’t stand it.C. I don’t mind.D. I think it’s ok.17.—Mr. Li is ill in hospital. His daughter is looking after him.— ______.A. I’m sorry to hear thatB. Not at allC. I’m afraidD. It doesn’t matter18. Which of the pictures below tells people not to fish here?A. B. C. D.19. Boys and girls, Listen to me carefully, Let me tell you______ to the Bird Island. .A. how to getB. what to getC. Where to getD. which to get20. —Excuse me. Do you know _____________?—Yes. He came here yesterday.A. why did he come to the zooB. how he came hereC. when he came back homeD. where he will came三、完型填空(每小题1分,共10分)请阅读下面短文,选择最佳答案。

2015年八年级下册数学期末试卷(带答案)

2015年八年级下册数学期末试卷(带答案)

2015年八年级下册数学期末试卷(带答案)2014/2015学年度第二学期期末质量检测八年级数学试卷一、选择题(本大题共有8小题,每小题3分,共24分.在每小题所给出的四个选项中,只有一项是符合题目要求的,请将正确选项的字母代号填涂在答题卡相应位置上) 1.每年4月23日是“世界读书日”,为了了解某校八年级500名学生对“世界读书日”的知晓情况,从中随机抽取了50名学生进行调查,在这次调查中,样本是 A.500名学生 B.所抽取的50名学生对“世界读书日”的知晓情况 C.50名学生 D.每一名学生对“世界读书日”的知晓情况 2.下列安全标志图中,是中心对称图形的是A B C D 3.下列计算正确的是 A. B. C. D. 4.一个盒子内装有大小、形状相同的四个球,其中红球1个、绿球1个、白球2个,小明摸出一个球是白球的概率是 A. B. C. D. 5.分式有意义,则x的取值范围是 A.x=1 B.x≠1 C.x=-1 D.x≠-1 6.若反比例函数的图象过点(2,1),则这个函数的图象一定过点 A.(2,-1) B.(1,-2) C.(-2,1) D.(-2,-1) 7.如图,平行四边形ABCD 中,下列说法一定正确的是 A.AC=BD B.AC⊥BD C.AB=CD D.AB=BC 8.如图,在矩形ABCD中,点E、F分别在边AB,BC上,且AE= AB.将矩形沿直线EF折叠,点B恰好落在AD边上的点P处,连接BP交EF 于点Q.对于下列结论:①EF=2BE,②PF=2PE;③FQ=4EQ;④△PBF 是等边三角形.其中正确的是 A.①② B.②③ C.①③ D.①④ 二、填空题(本大题共有10小题,每小题2分,共20分.不需写出解答过程,请将答案直接写在答题卡相应位置上) 9.若二次根式有意义,则的取值范围是▲ . 10.若菱形两条对角线的长分别为6和8,则这个菱形的面积为▲ . 11.若关于的分式方程有增根,则这个增根是▲ . 12.已知y是x的反比例函数,当x > 0时,y 随x的增大而减小.请写出一个满足以上条件的函数表达式▲ . 13.计算▲ . 14.已知,则的值等于▲ . 15.已知一只纸箱中装有除颜色外完全相同的红色、黄色、蓝色乒乓球共100个.从纸箱中任意摸出一球,摸到红色球、黄色球的概率分别是0.2 、0.3.则纸箱中蓝色球有▲ 个. 16.如图,矩形中,,,是边上的中点,是边上的一动点,,分别是、的中点,则随着点的运动,线段长的取值或取值范围为▲ .17.直线与双曲线交于、两点,则的值是▲ . 18.图1是一个八角星形纸板,图中有八个直角,八个相等的钝角,每条边都相等.如图2将纸板沿虚线进行切割,无缝隙无重叠的拼成图3所示的大正方形,其面积为8+4 ,则图3中线段AB的长为▲ .三、解答题(本大题共有9小题,共76分.请在答题卡指定区域内作答,解答时应写出文字说明、推理过程或演算步骤) 19.(本题满分5分)计算: 20.(本题满分5分)解方程: 21.(本题满分6分) 化简并求值:,其中22.(本题满分6分) 网瘾低龄化问题已引起社会各界的高度关注,有关部门在全国范围内对12�35岁的网瘾人群进行了简单的随机抽样调查,得到了如图所示的两个不完全统计图.请根据图中的信息,解决下列问题:(1)求条形统计图中a的值;(2)求扇形统计图中18�23岁部分所占的百分比;(3)据报道,目前我国12�35岁网瘾人数约为2000万,请估计其中12�23岁的人数.23.(本题满分8分)已知,如图,是的角平分线,点、分别在、上,且∥ ,∥ .求证:24.(本题满分10分) 甲、乙两台机器加工相同的零件,甲机器加工160个零件所用的时间与乙机器加工120个零件所用的时间相等.已知甲、乙两台机器每小时共加工35个零件,求甲、乙两台机器每小时各加工多少个零件?25.(本题满分12分)如图,一次函数的图象与反比例函数y= �C 3x的图像交于、两点,与x轴交于点,且、两点关于y轴对称.(1)求、两点的坐标以及一次函数的函数关系式; (2)求的面积.(3)在 x轴上是否存在点,使得的值最大.若存在,求出点的坐标,若不存在,请说明理由. 26.(本题满分12分)(1)如图1,、是正方形的边及延长线上的点,且,则与的数量关系是▲ . (2)如图2,、是等腰的边及延长线上的点,且,连接交于点,交于点,试判断与的数量关系,并说明理由;(3)如图3,已知矩形的一条边,将矩形沿过的直线折叠,使得顶点落在边上的点处。

2015---2016学年第二学期期末考试题(卷)

2015---2016学年第二学期期末考试题(卷)

2015---2016学年第二学期期末考试题(卷)第一部分选择题(共60分)一.选择题:本大题共12小题,每小题5分,共60分. 在每小题给出的四个选项中,只有一项是符合题目要求的.1.已知全集,集合,,则()A. B. C.D.2.已知Z= (i为虚数单位),则Z的共轭复数在复平面内对应的点位于()A.第一象限B.第二象限C.第三象限 D.第四象限3.已知非零向量与向量平行,则实数的值为()第4题图A.或 B.或C. D.4.执行如图所示的程序框图,输出的S值为( )A.1 B.C.D.5.设的内角,,的对边分别为,,.若,,,且,则()A. B.C.D.6.设数列是等差数列,为其前项和.若,,则()A. B. C. D.7. 抛物线的焦点到其准线的距离是()A. B.C.D.8.已知命题:存在∈(1,2)使得,若是真命题,则实数的取值范围为()第9题图A. (-∞,)B. (-∞,]C. (,+∞)D. [,+∞)9. 已知函数的部分图象如图所示,若将图像上的所有点向右平移个单位得到函数的图像,第10题图则函数的单调递增区间为()A.,B.,C.,D.,10.如图为某几何体的三视图,则该几何体的外接球的表面积为( )A.31π B.32π C.34π D.36π11. 以椭圆内的点为中点的弦所在的直线方程为( )A. B.C. D.12. 设,则关于,的方程所表示的曲线是( )A.长轴在轴上的椭圆 B.长轴在轴上的椭圆C.实轴在轴上的双曲线 D.实轴在轴上的双曲线第二部分非选择题(共90分)二、填空题:本大题共4小题,每小题5分,满分20分. 13.已知直线过圆的圆心,且与直线垂直,则直线的方程为 .14.实数满足,则的最大值为 . 15.设△ABC的内角为A,B,C,所对的边分别是,,.若,则角C=__________.16. 已知椭圆的左、右焦点分别为,点为椭圆上一点,且,,则椭圆的离心率等于.三、解答题:本大题共 8小题,满分 70 分。

2015年第二学期八年级物理期末试卷及答案

2015年第二学期八年级物理期末试卷及答案

2015年第二学期八年级物理期末试卷(力学)(g 取10N/kg )一、选择题(本题共15小题,每小题2分,共30分,每题只有一个正确答案。

) 1.如图所示的实例中,目的是为了增大压强的是( ▲ )2.下列事例中不是利用大气压的是 ( ▲ )A.把吸盘式挂衣钩紧贴到墙上后可挂衣服 B.用胶头滴管吸取药液C.茶壶的盖上留一小孔,水才容易倒出来D.用力压打气筒的活塞,把气充进轮胎中 3.如图1所示,用两食指同时压铅笔两端,左手指受到笔尖的压力为F 1,压强为p 1,右手指受到的压力为F 2,压强为p 2,下列说法正确的是( ▲ ) A .F 1<F 2 B .F l > F 2 C .p 1<p 2 D .p 1>p 24.铅笔盒放在水平桌面上,静止时,在下列各对力中属于平衡力的是( ▲ ) A .桌面对铅笔盒的支持力与铅笔盒对桌面的压力 B .桌子受到的重力与铅笔盒受到的重力 C .铅笔盒受到的重力与桌面对铅笔盒的支持力 D .铅笔盒对桌面的压力与地面对桌子的支持力5.如图2所示,小车上的木块突然向左倾倒,发生这一现象的原因是( ▲ ) A .小车突然向左运动 B .小车突然向右运动 C .向右运动的小车突然停下 D .以上原因都有可能6.歼击机在进入战斗状态时要丢掉副油箱,这样做是为了( ▲ )A.减小质量,使运动状态易于改变B.减小质量,使运动状态不易改变C.增大惯性,使运动状态易于改变D.增大惯性,使运动状态不易改变 7.小刚用水平推力推静止在水平地面上的讲台桌,结果没有推动(如图3所示)。

则下列说法正确的是 ( ▲ )A .讲台桌不受摩擦力B .推力与讲台桌的重力大小相等A 铁轨下铺枕木B 坦克装有履带 D 书包背带很宽C 刀刃磨得很薄图1图2图3C .推力小于地面对讲台桌的摩擦力D .推力与地面对讲台桌的摩擦力大小相等8.体育课上常有爬绳索和爬滑杆两种运动.体重相同的小明和小华两人想比赛看谁爬杆爬的快.两人先后以相同的姿势匀速向上爬,以下说法正确的是( ▲ ) A .小华爬绳和小明爬杆受到的摩擦力一样大 B .小华爬绳受到的摩擦力的方向是竖直向下C .若小华和小明爬杆和爬绳的速度不一样,则速度大的人受到的摩擦力要大些D .小明爬绳时自身的重力和手对绳的拉力是一对平衡力 9.关于力和运动的关系,下列说法中正确的是 ( ▲ ) A.力是维持物体运动状态的原因 B.力是改变物体运动状态的原因 C.只有在力的作用下物体才能运动D.只要有力作用在物体上,物体的运动状态就一定改变10.沙漠中有一个沙丘(如图4),当水平方向的风不断吹过沙丘时,沙丘会慢慢:( ▲ ) A 、向左移动 B 、向右移动 C 、仍停原处 D 、无法确定11. 如图5所示,有一热气球正以8m/s 速度匀速竖直上升,至某一高度时,从气球里掉出一个物体,这个物体离开气球后将 ( ▲ ) A. 立即下落 B.继续上升一段距离,然后下落 C.以原来速度一直上升 D.以上说法均不对12.在水平轨道上做匀速直线运动的列车车厢的天花板上悬吊一个小球a ,地板上有b 、c 、d 三点,其中b 点位于小球a 的正下方,如图6所示,若空气阻力不计,烧断细线后,小球a 将 ( ▲ ) A.落在b 点上 B.可能落在bc 两点之间 C.落在d 点上 D.可能落在bd 两点之间13.高度、材料相同的实心长方体A 和B 放在水平桌面上,它们的大小如图7所示。

2015学年广东华侨中学八年级第二学期期末考(附答案)

2015学年广东华侨中学八年级第二学期期末考(附答案)

2015学年广东华侨中学八年级第二学期期末考试英语试卷一、语法选择(共15小题;每小题1分,满分15分)阅读下面短文,按照句子结构的语法性和上下文连贯的要求,从每题所给的四个选项中选出最佳选项。

We are lucky to live in a rich country where we have many things. _____1_____, most of us usually waste a lot.Electricity is one thing that we waste _____2_____. Lights, TVs, radios and other things are often _____3_____ on even when no one is using them. We should turn them off when we do not need them. It _____4_____ less than a second to do it. Anyhow, not wasting electricity saves money, because we do not _____5_____ keep the electricity on when we do not use it.The second thing that we often waste is water. Fresh water is valuable, _____6_____ it shouldn’t be wasted. It is only a simple matter of turning off a tap. I am sure everybody can do this _____7_____ if he wants to._____8_____ big waste is food. My mother used to cook so much food _____9_____ much of it was thrown away. I told her we _____10_____ so much food. She thought I was right and now she only cook what we can eat._____11_____ is not right to be wasteful. I find there is _____12_____ simple way of not wasting things. That is to use only _____13_____ we need . Do not touch what we do not need. _____14_____ this way we can stop _____15_____ wasteful.1. A. Instead B. Therefore C. However D. Besides2. A. most B. more C. many D. lot3. A. keep B. kept C. keeping D. to keep4. A. take B. to take C. taking D. takes5. A. have to B. must C. can D. may6. A. or B. so C. because D. but7. A. easy B. easier C. easily D. more easily8. A. The other B. Other C. Others D. Another9. A. which B. that C. what D. when10. A. waste B. wastes C. was wasted D. were wasting11. A. It B. That C. There D. She12. A. an B. the C. a D. /13. A. that B. what C. which D. when14. A. By B. On C. From D. In15. A. be B. to be C. being D. been二、完形填空(共10小题,每小题1.5分,满分15分)阅读下面短文,掌握其大意,然后从每题所给的四个选项中选出最佳选项。

2015年北师大版八年级下物理期末试卷

2015年北师大版八年级下物理期末试卷

第二学期期末考试·八年级物理·试卷题号一二三四五总分总分人复核人得分一、选择题(每题2分,共30分)1.如图所示,人眼处在合适位置,都能观察到清晰的像,下列说法正确的是( )A.图①成正立缩小的实像B.图②成正立等大的实像C.图③成倒立缩小的实像D.图④成正立放大的虚像2.如图所示,表示近视眼矫正的是( )3.某同学将物体放在凸透镜前,使物距分别为6cm、18cm、24cm时,依次得到放大虚像、放大实像和缩小实像,该凸透镜的焦距为f则( )A.6cm<f<9cmB.9cm<f<12cmC.12cm<f<18cmD.18cm<f<24cm4.下课时,有同学用力推课桌的下部,课桌会沿地面滑动;而推课桌的上部,课桌可能会翻倒,这说明力的作用效果( )A.与力的大小有关B.与力的作用点有关C.与力的方向有关D.与受力面积有关5.某物体在平衡力的作用下,做匀速直线运动。

若它所受的平衡力突然全部消失,则物体将( )A.立即停止运动B.逐渐减慢,最终停下来C.仍然做匀速直线运动D.在水平方向上匀速直线运动下去6.如图所示,小明用水平力推车而车未动,下列说法中正确的是( ) A.小明的推力做了功 B.车不受摩擦力C.小明的推力小于车受到的摩擦力D.地面对车的支持力与车受到的重力是一对平衡力7.你在上体育课时,遇到了下列一些场景,并由此联想到学过的物理知识,下列联想错误的是( )A.“跳远助跑”时利用了惯性的原理B.“引体向上”时手搓镁粉利用了增大摩擦的道理C.“踢足球”时利用了力使物体运动状态发生改变的道理D.“仰卧起坐”时利用了大气压的原理8.下列四幅图中,利用相关部件减小压强的是( )9.关于压力的说法中,正确的是:()A 压力的大小总等于物体重力大小B 压力的方向总是竖直向下C 压力的方向总垂直于物体表面D 压力的大小决定了压强大小10.静止液体内部某点的压强,与下面哪个因素有关:()A 全部液体的重力B 液体的体积C 容器底面积的大小D 液体的密度11.如图所示,甲、乙两支完全相同的试管,分别装有质量相等的液体,甲试管竖直放置,乙试管倾斜放置,两试管液面相平。

2015学年各地区期末试题J022——贵州省安顺市2015年八年级下期末考试数学试题及答案

2015学年各地区期末试题J022——贵州省安顺市2015年八年级下期末考试数学试题及答案

2014-2015学年度第二学期期末教学质量检测试卷八年级 数 学(时间:100分钟,满分100分)一、选择题(本大题共10题,每小题3分,共30分) 1.下列各式3225,5,,2,21⑤④③②①-+y x x 其中二次根式的个数有 A 、1个 B 、2个 C 、3个 D 、4个 2.下列各组数据中的三个数,可构成直角三角形的是( )A 、4,5,6B 、2,3,4C 、11,12,13D 、8,15,17 3.下列给出的条件中,能判定四边形ABCD 是平行四边形的是( )A 、AB ∥CD ,AD=BC B 、AB=AD ,CB=CD C 、AB=CD ,AD=BC D 、∠B=∠C ,∠A=∠D 4.若m -3为二次根式,则m 的取值为( )A 、m≤3B 、m <3C 、m≥3D 、m >3 5. 下列计算正确的是( ) ①694)9)(4(=-⋅-=--; ②694)9)(4(=⋅=--;③145454522=-⋅+=-; ④145452222=-=-;A 、1个B 、2个C 、3个D 、4个 6.一次函数y=-5x+3的图象经过的象限是( )A 、一、二、三B 、二、三、四C 、一、二、四D 、一、三、四 7. 在Rt △ABC 中,AB=3,AC=4,则BC 的长为( ). A 、5B 、7C 、5或7D 、无法确定8.数据10,10,x ,8的众数与平均数相同,那么这组数的中位数是( ) A 、10 B 、8 C 、12 D 、49.如果三角形的两边分别为4和6,那么连接该三角形三边中点所得三角形的周长 可能是( )A 、6B 、8C 、10D 、1210.函数y =ax +b 与y =bx +a 的图象在同一坐标系内的大致位置正确的是( )A. B. C. D.二、填空题(本大题共8题,每小题3分, 共24分) 11.计算:312-=_______。

12.若2m x y =是正比例函数,则m=_______。

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2015.2期末考试试题
附加:如图甲所示的电路中,电源电压保持不变,R0为定值电阻,R为滑动变阻器.闭合开关S后,在移动滑片P的过程中,电流表的示数I与R的阻值关系如图乙所示,电压表的示数U与R的阻值关系如图丙所示,则R0的阻值为Ω,电源电压为V.
解:由电路图可知,R与R0串联,电压表测R0两端的电压,电流表测电路中的电流.
由图乙可知,滑动变阻器接入电路中的阻值R1=20Ω时,电路中的电流I1=0.4A,
因串联电路中总电阻等于各分电阻之和,
所以,由I=可得,电源的电压:
U=I1(R0+R1)=0.4A×(R0+20Ω),
由图丙可知,滑动变阻器接入电路中的电阻R2=30Ω时,电压表的示数U0=3V,
因串联电路中各处的电流相等,
所以,电路中的电流:
I2==,
电源的电压:U=I2(R0+R2)=×(R0+30Ω),
因电源的电压不变,所以,0.4A×(R0+20Ω)=×(R0+30Ω),
整理可得:R02﹣25Ω×R0+450Ω2=0,解得:R0=22.5Ω,R0=﹣10Ω舍去,
电源的电压U=I1(R0+R1)=0.4A×(22.5Ω+20Ω)=17V.故答案为:22.5;17.
(附加3)如图(a)所示的电路,电源电压保持不变,闭合开关S,调节滑动变阻器,两电压表的
示数随电路中电流变化的图象如图(b)所示.由图(b)可以看出:电源电压为______V,R
2
接入电路的阻值变化范围是______Ω.
由a电路图可知,当滑动变阻器的滑片P,向右移动时,连入电阻变大,电路中电流变小,R
1
两端的电压
同时变小,电源电压保持不变,R
2两端的电压就要变大;结合图b可知,甲是R
1
的U-I图象,乙是R
2

U-I图象.
(1)由图象可知,当U
1
=U2=3V时,I=0.3A,由此可求电源电压:U=U1+U2=6V;
(2)当U
2
=4V时滑动变阻器全连入,此时I=0.2A,
根据欧姆定律可得:
滑动变阻器的最大电阻是R=4V/0.2A=20Ω,
所以R
2
接入电路的阻值变化范围是0~20Ω.
故答案为:6;0~20.
2、如图a所示的电路中,电源电压保持不变.闭合开关S,调节滑动变阻器,两电压表的示数随电路中电
试题分析:(1)由a电路图可知,当滑动变阻器的滑片P,向右移动时,连入电阻变大,电路中电流变小,R1两端的电压同时变小,电源电压保持不变,R2两端的电压就要变大;
结合图b可知,甲是R1的U-I图象即电压表V1示数变化的图象,乙是R2的U-I图象即压表V2示数变化的图象;
(2)由图象可知,当U1=U2=3V时,I=0.15A,
∵串联电路中总电压等于各分电压之和,
∴电源电压U=U1+U2=3V+3V=6V;
∵I=U/R,∴R1=U1/I=3V/0.15A=20Ω.
举一反三:如图甲所示的电路,电源电压保持不变.闭合开关S,调节滑动变阻器,两电压表的示数随电路中电流变化的图线如图乙所示.根据图线的信息可知()
A.电阻R1与R2是并联连接的
B.甲是电压表V2示数变化的图线
C.电阻R1的阻值为10Ω
D.电源电压为3V
查看答案
如图a所示的电路,电源电压保持不变.闭合开关S,当滑动变阻器的滑片P从a端滑到b端的过程中,两电压表的示数随电路中电流变化的图线如图b所示,根据图线的信息可知:_____(选填“甲”或“乙”)是电压表V2示数变化的图线,电源电压为_____V,滑动变阻器的最大阻值为_____Ω.
查看答案
如图甲所示的电路,电源电压保持不变.闭合开关S,调节滑动变阻器,两电压表的示数随电路中电流变化的图线如图乙所示.根据图线的信息可知:_____(甲/乙)是电压表V2示数变化的图线,电源电压为
_____V.。

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