北京市东城2012--2013学年第二学期初三综合练习(二)(含答案)word版
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2013年初三物理二模试卷(含答案东城区)北京市东城区2012-2013学年第二学期初三综合练习(二)物理试卷学校班级姓名考号一、单项选择题(下列各小题中只有一个选项符合题意。
共28分,每小题2分。
)1.在国际单位制中力的单位是A.牛顿(N)B.帕斯卡(Pa)C.焦耳(J)D.瓦特(W)2.图1所示的四种现象中,不符合安全用电原则的是3.图2所示的四种现象中,属于光的折射现象的是4.将经过冷冻的瓶装矿泉水从冰箱中取出后,发现瓶子的外表面附着了一层小水滴,其物态变化过程正确的是A.液化放出热量B.熔化吸收热量C.凝华放出热量D.升华吸收热量5.如图3所示是小东制作的昆虫观察盒,在盒盖上端安装凸透镜便于观察盒内小昆虫放大的像,盒盖到盒底的距离为10cm。
他应该选择A.焦距为5cm的凸透镜B.焦距为8cm的凸透镜C.焦距为10cm的凸透镜D.焦距为12cm的凸透镜6.下列说法正确的是A.吹长笛时发出的声音是长笛管内空气柱振动产生的B.吉它能弹奏出不同的音阶,是拔弦时用力大小不同C.我们能区别两个同学的声音,是因为他们的音调不同D.我们听不到真空罩内的铃声,是因为只有空气能传声7.将一金属块挂在竖直的弹簧测力计挂钩上,并处于静止状态。
金属块所受的重力为G,金属块对弹簧测力计的拉力为F1,弹簧测力计对金属块的拉力为F2,下列说法正确的是A.F1与F2是一对平衡力B.G与F2是一对平衡力C.G与F1是一对平衡力D.G与F1是一对相互作用力8.图4是某物理小组设计的拍摄机动车辆闯红灯设备的原理示意图。
红灯亮时,光控开关接收到红光会闭合;机动车驶过时,安装在路面下方的压力开关受到机动车的压力会闭合。
当摄像系统的电路自动拍摄违章车辆时,关于开关的状态下列说法中正确的是A.只有光控开关处于闭合状态B.只有压力开关处于闭合状态C.光控开关和压力开关同时处于闭合状态D.若将两开关并联也能达到相同的效果9.如图5所示是一种风速测定装置。
北京市东城区2012-2013学年第二学期初三综合练习(二)物 理 试 卷学校 班级 姓名 考号一、单项选择题(下列各小题中只有一个选项符合题意。
共28分,每小题2分。
) 1.在国际单位制中力的单位是A .牛顿(N)B .帕斯卡(Pa)C .焦耳(J)D .瓦特 (W)2.图1所示的四种现象中,不.符合安全用电原则的是3.图2所示的四种现象中,属于光的折射现象的是4.将经过冷冻的瓶装矿泉水从冰箱中取出后,发现瓶子的外表面附着了一层小水滴,其物态变化过程正确的是A .液化 放出热量B .熔化 吸收热量C .凝华 放出热量D .升华 吸收热量5.如图3所示是小东制作的昆虫观察盒,在盒盖上端安装凸透镜便于观察盒内小昆虫放大的像,盒盖到盒底的距离为10cm 。
他应该选择A .焦距为5cm 的凸透镜B .焦距为8cm 的凸透镜C .焦距为10cm 的凸透镜D .焦距为12cm 的凸透镜6.下列说法正确的是A .吹长笛时发出的声音是长笛管内空气柱振动产生的B .吉它能弹奏出不同的音阶,是拔弦时用力大小不同C .我们能区别两个同学的声音,是因为他们的音调不同图2A .日全食现象C .树在水中的倒影 B .铅笔在水面“折断”D .花瓶在镜子中的像 图1B .擦拭用电器D .用绝缘棒挑开绝缘棒 A .电器金属外壳C .在高压线附图3图6 D .我们听不到真空罩内的铃声,是因为只有空气能传声7.将一金属块挂在竖直的弹簧测力计挂钩上,并处于静止状态。
金属块所受的重力为G ,金属块对弹簧测力计的拉力为F 1,弹簧测力计对金属块的拉力为F 2,下列说法正确的是A .F 1与F 2是一对平衡力B .G 与F 2是一对平衡力C .G 与F 1是一对平衡力D .G 与F 1是一对相互作用力8.图4是某物理小组设计的拍摄机动车辆闯红灯设备的原理示意图。
红灯亮时,光控开关接收到红光会闭合;机动车驶过时,安装在路面下方的压力开关受到机动车的压力会闭合。
北京市东城区2011--2012学年第二学期初三综合练习(二)数学试卷参考答案一、选择题(本题共32分,每小题4分)二、填空题(本题共16分,每小题4分)三、解答题:(本题共30分,每小题5分)13.解:原式=164-分=1……5分14. 解:+①②得:23x x+=1x=.……2分将1x=代入②得:12y-=,1y=……4分11xy=⎧∴⎨=-⎩……5分15. 证明:∵AC平分BCD BC∠,平分ABC∠,∴ACB DBC=∠∠……2分在ABC△与DCB△中,A B C D C BA CB D B CB C B C=⎧⎪=⎨⎪=⎩∠∠∠∠ABC∴△DCB≌△……4分AB DC ∴=.……5分16. 解:原式=()()()()()()22111111111x x x x x x x x x x x x -+---+÷==+--·……3分当2x =-时,原式=211.22-+=-……5分 17. 解:据题意,得1(8)(6)862x x --=⨯⨯.解得12122x x ==,.1x 不合题意,舍去.2x ∴=.18.解: (1)∵4=3k- 12k =- ∴12y x-=……2分(2)∵BC =a -(-3)=a +3 AC =4, ∴14(3)2ACB S a ∆=⨯⨯+ ……4分=2a +6 (a >-3)……5分四、解答题(本题共20分,每小题5分) 19.解:(1) 15,0.16;……2分 (2)144︒;……3分(3)271000[(1584)50]100054050⨯++÷=⨯=(人)……5分 答:该校平均每周做家务时间不少于4小时的学生约有540人 20.解: 在△ABE 中,AE BC ⊥,5AB =,53cos =B ∴BE=3,AE=4.∴EC=BC-BE =8-3=5. ∵平行四边形ABCD, ∴CD=AB=5.∴△CED 为等腰三角形.……2分∴∠CDE =∠CED .∵ AD//BC, ∴∠ADE =∠CED . ∴∠CDE =∠ADE .在Rt △ADE 中,AE =4,AD=BC =8,41tan .82CDE ∴∠== 21.解:(1)直线CE 与O ⊙相切 证明:∵矩形ABCD , ∴BC//AD ,∠ACB =∠DAC . ∵,ACB DCE ∠=∠ ∴.DAC DCE ∠=∠……1分 连接OE,则.DAC AEO DCE ∠=∠=∠90,90.90.2D CE D E C A E O D E C O E C ∠+∠=∴∠+∠=∴∠=分 ∴直线CE 与O ⊙相切.22222 AB (2)tan 2,tan 3,tan D tan D 1.,4 ,CO 3, 54ACB BC BC AB BC ACB AC ACB DCE CE DE DC CE Rt CDE CE O Rt CE O CE EOr r ∠===∴=⋅∠==∠=∠∴∠=∴=⋅∠=∆=∆=+=+=分在中分设⊙的半径为r, 则在中即解得分22.解:(1)4i =1,2011i=-i 20121i =……3分(2)方程2220x x -+=的两根为 1+i 和 1-i ……5分五.解答题(本题共22分,第23题7分,第24题7分,第25题8分)A23.解:(1)2(4)12(1)m m ∆=---2(2)m =+.……2分由题意得,2(2)m +>0且10m -≠ .∴ 符合题意的m 的取值范围是 21m m ≠-≠且的一切实数. ……3分(2)∵ 正整数m 满足822m ->, ∴ m 可取的值为1和2 .又∵ 二次函数2(1)(4)3y m x m x =-+-+,∴ m =2.……4分∴ 二次函数为2-23y x x =++.∴ A 点、B 点的坐标分别为(-1,0)、(3,0).依题意翻折后的图象如图所示.由图象可知符合题意的直线3y kx =+经过点A 、B .可求出此时k 的值分别为3或-1.……7分注:若学生利用直线与抛物线相切求出k =2也是符合题意的答案. 24. 解: (1) AM CN MN =+……2分 (2)AM CN MN =+……3分证明:过点O 作,,OD AC OE BC ⊥⊥易得,120,OD OE DOE =∠= 在边AC 上截得DN’=NE ,连结ON ’, ∵ DN ’=NE , OD =OE , ∠ODN ’=∠OEN'.DON EON ∴∆≅∆……4分 ∴ON’=OE. ∠DON ’=∠NOE .120,DOE ∠=60,MON ∠=∴∠MOD +∠NOE=600.∴∠MOD +∠DON ’=600.易证'MON MON ∆≅∆.……5分 ∴MN’=MN.'.,,()(),.MN MD DN MD NE MD AM AD AM CE NE CE CN MN AM CE CE CN AM CN AM CN MN ∴=+=+=-=-=-∴=-+-=-∴=+(3) .MN CN AM =+……7分25.解:(1)由题意,得:3,9-60.c a a c =⎧⎨+=⎩…解得:-1,3.a c =⎧⎨=⎩所以,所求二次函数的解析式为:2--23y x x =+……2分 顶点D 的坐标为(-1,4).……3分 (2)易求四边形ACDB 的面积为9. 可得直线BD 的解析式为y=2x+6设直线OM 与直线BD 交于点E ,则△OBE 的面积可以为3或6. ① 当1=9=33OBE S ∆⨯时,易得E 点坐标(-2,-2),直线OE 设M 点坐标(x ,-x ),212---2 3.-122x x x x x =++==(舍),∴M ……4分② 当1=9=63OBE S ∆⨯时,同理可得M 点坐标. ∴ M 点坐标为(-1,4)……5分(3)连接OP ,设P 点的坐标为(),m n ,因为点P 在抛物线上,所以232n m m =-+-, 所以PB PO OPB OB S S S S =+-△C △C △△C ……6分111()222OC m OB n OC OB =⋅-+⋅-⋅ ()339332222m n n m =-+-=--()22333273.2228m m m ⎛⎫=-+=-++ ⎪⎝⎭ ……7分因为3<0m -<,所以当32m =-时,154n =. △CPB 的面积有最大值27.8 ……8分所以当点P 的坐标为315(,)24-时,△CPB 的面积有最大值,且最大值为27.8。
北京市东城区2011—2012学年第二学期初三综合练习(二)英语试卷2012.6 学校___________ 班级_____________ 姓名_____________ 考号______________考生须知1. 本试卷共12页,满分120分,考试时间120分钟。
2. 在试卷和答题卡上准确填写学校名称、班级、姓名和考号。
3. 试题答案一律填涂或书写在答题卡上,在试卷上作答无效。
4. 在答题卡上,选择题用2B铅笔作答,其他试题用黑色字迹签字笔作答。
5. 考试结束,请将本试卷和答题卡一并交回。
听力理解(共26分)一、听对话,从下面各题所给的A、B、C三幅图片中选择与对话内容相符的图片。
每段对话读两遍。
(共4分,每小题1分)1.A. B. C.2.A. B. C.3.A. B. C.4.A. B. C.二、听对话或独白,根据对话或独白的内容,从下面各题所给的A、B、C三个选项中选择最佳选项。
每段对话或独白读两遍。
(共12分,每小题1分)请听一段对话,完成第5至第6小题。
5. When is Tony’s birthday?A. May 10th.B. June 10th.C. July 10th.6. How is Tony going to celebrate his birthday?A. To visit a park.B. To have a big meal.C. To see a movie.请听一段对话,完成第7至第8小题。
7. Who’s Peter?A. Mary’s classmate.B. Mary’s brother.C. Mary’s neighbor.8. Where is Peter now?A. In America.B. In Europe.C. In Asia.请听一段对话,完成第9至第10小题。
9. What’s the girl practicing for?A. The sports meet.B. The school concert.C. The final exam.10. How does the boy get the latest weather report?A. On the radio.B. On TV.C. On the Internet.请听一段对话,完成第11至第13小题。
2012 北京市东城区初三英语二 模试题与答案-2北京市东城区 2011—2012 学年第二学期初三综合练习(二)英语试卷2012.6学校___________ 班级_____________ 姓名_____________ 考号______________1. 本试卷共 12 页,满分 120 分,考试 时间 120 分钟。
2. 在试卷和答题卡上准确填写学校名 考 称、班级、姓名和考号。
生 3. 试题答案一律填涂或书写在答题卡 须 上,在试卷上作答无效。
知 4. 在答题卡上,选择题用 2B 铅笔作 答,其他试题用黑色字迹签字笔作答。
5. 考试结束,请将本试卷和答题卡一 并交回。
听力理解 (共 26 分)一、听对话,从下面各题所给的 A、B、C 三幅图片中选择与对话内容相符的图 片。
每段对话读两遍。
(共 4 分,每小题 1 分)1.A.B.C.2.初三英语试卷 第2页(共 12 页)初三英语试卷 第3页(共 12 页)11. How long is Steven going to stay at the beach?A. For the summer.B. For a week.hours.12. Where is Jane going to work?A. In a restaurant.B. In a cinema.13. What are they mainly talking about?A. Summer holiday jobs.B. Summer holiday plans.C. Summer holiday camps.请听一段独白,完成第 14 至第 16 小题。
14. Why did Lucy start a new magazine?A. She wanted to be famous.B. She wanted to get more experience.C. She wanted to do something different.15. How many parts are there in the magazine?A. Two.B. Three.16. What do you know about the magazine?A. It has the latest news.B. It has some ads for restaurants.C. It has articles about the people in the town.C. For seven C. In a store.C. Four.三、听对话,根据所听到的对话内容和提示词语,记录关键信息。
北京市东城区2012-2013学年第二学期初三综合练习(二)化学试卷H 1 C 12 N 14 O 16 Na 23 Al 27 S 32 Ca 40 Fe 56 I 127一、选择题(每小题只有一个选项符合题意。
共25个小题,每小题1分,共25分。
)1.保持氢气化学性质的最小粒子是A.H2B.H2O C.H D.H+2.化学与生活密切相关。
下列食物能为人体提供糖类的是A.蔬菜B.牛奶C.大米D.花生3.化学反应前后一定发生变化的是A.原子数目B.原子质量C.元素种类D.物质种类4.下列物质中,不属于...溶液的是A.泥水B.硬水C.矿泉水D.生理盐水5.下列能源中,容易获得且不会..对环境造成污染的是A.石油B.天然气C.氢气D.太阳能6.下列物质的化学式书写不正确...的是A.氧化钠NaO2 B.氧化铝Al2O3C.硫酸镁MgSO4 D.氢氧化铜Cu(OH)27.空气是一种重要的自然资源。
下列关于空气的说法正确的是A.空气是由多种物质组成的混合物B.空气污染指数越高,空气质量越好C.人体呼吸时吸入的是空气,呼出的全部是CO2D.空气中含量最多的气体是O2,所以空气是纯净物8.下列气体不能..用NaOH固体干燥的是A.O2B.CO2C.H2D.N29.下列属于复合肥料的是A.尿素[CO(NH2)2] B.硫酸钾(K2SO4)C.磷酸铵[ (NH4)3PO4 ] D.碳酸氢铵(NH4HCO3)10.硅是信息技术的关键材料。
工业上制备硅的反应SiO2 + 2C高温Si + 2CO↑ 属于A .分解反应B .化合反应C .置换反应D .复分解反应 11.分子和原子的主要区别是 A .分子运动,原子不运动 B .分子质量大,原子质量小C .分子间有间隔,原子间无间隔D .在化学反应中,分子可分而原子不可分12.下列做法不符合...“低碳生活”理念的是 A .减少使用一次性纸制品 B .保持饮水机24小时开启 C .选择可反复使用的购物袋 D .养成随手关灯的习惯 13.通常铝制品耐腐蚀的原因是A .铝的化学性质不活泼B .铝是银白色固体C .铝的表面有一层致密的氧化铝薄膜D .铝的密度较小14.工业上用甲和乙反应制备燃料丙。
北京市东城区2012—2013学年第二学期初三综合练习(二)语文试卷2013.6学校班级姓名考号一、选择。
下面各题均有四个选项,其中只有一个符合题意,选出答案后在答题卡上用2B 铅笔把对应的题目的选项字母涂黑涂满。
(共12分。
每小题2分)1.下列词语中加点字读音完全正确的一项是A.沟壑(hè) 炫耀(xuán)避讳(huì)谆谆教诲(zhūn)B.细菌(jūn)提防(dī)滑稽(jī)功亏一篑(kuì)C.静谧(mì)犀利(xī)捕捉(pǔ)重蹈覆辙(zhé)D.颈椎(jǐnɡ)恣意(zì)闲暇(xiá)自给自足(gěi)2. 依据下列各组词语中加点字的解释,判断词语意思正确的一项是A.鉴赏——前车之鉴解释:“鉴”有“仔细看”“审察”的意思。
判断:“鉴赏”指仔细观看、欣赏;“前车之鉴”指仔细审察以前犯下的错误。
B.涉猎——跋山涉水解释:“涉”有“从水上经过”的意思。
判断:“涉猎”指渡水、打猎;“跋山涉水”指翻越山岭,蹚水过河。
C.本色——舍本逐末解释:“本”有“原来”的意思。
判断:“本色”指本来面貌,原有的性质或品质;“舍本逐末”指舍弃事物原有的部分而追求细枝末节。
D.称职——称心如意解释:“称”有“适合”“相当”的意思。
判断:“称职”指思想水平和工作能力能适合所担任的职务;“称心如意”指符合意愿,内心满足。
3.下列句子中加点成语或俗语使用有误的一项是A.5月初,景山公园的牡丹开得正好,从势头上看,比园中其他种类的花要略胜一筹。
B.他的讲座深入浅出,居高临下地阐述了青少年的前途与国家现代化建设之间的关系。
C.“海阔凭鱼跃,天高任鸟飞”,只要我们拥有过硬本领,就一定能找到施展才华的地方。
D.学习上的收获与学习过程中的付出是成正比的,正所谓“种瓜得瓜,种豆得豆”。
4.下列句子的标点符号使用正确的一项是A.他在海边写浪花,写礁石;在山顶写青松,写老藤;在原野写春花,写秋月:他饱含激情,进行创作。
2012 北京市东城区初三英语二 模试题与答案-2D初三英语试卷 第2页(共 12 页)初三英语试卷 第3页(共 12 页)A.B.C.3.A.B.C.4.A.B.C.二、听对话或独白,根据对话或独白的内容,从下面各题所给的 A、B、C 三个选项中选择最佳选项。
每段对话或独白读两遍。
(共 12 分,每小题 1 分)请听一段对话,完成第 5 至第 6 小题。
5. When is Tony’s birthday?A. May 10th.B. June 10th.6. How is Tony going to celebrate his birthday?C. July 10th.A. To visit a park.B. To have a big meal.请听一段对话,完成第 7 至第 8 小题。
C. To see a movie.7. Who’s Peter?A. Mary’s classmate.B. Mary’s brother.C.Mary’sneighbor.8. Where is Peter now?A. In America.B. In Europe.请听一段对话,完成第 9 至第 10 小题。
C. In Asia.9. What’s the girl practicing for?A. The sports meet.B. The school concert.C. The finalexam.10. How does the boy get the latest weather report?A. On the radio.B. On TV.C. On the Internet.请听一段对话,完成第 11 至第 13 小题。
初三英语试卷 第4页(共 12 页)11. How long is Steven going to stay at the beach?A. For the summer.B. For a week.hours.12. Where is Jane going to work?A. In a restaurant.B. In a cinema.13. What are they mainly talking about?A. Summer holiday jobs.B. Summer holiday plans.C. Summer holiday camps.请听一段独白,完成第 14 至第 16 小题。
2012——2013学年第二学期初三综合练习(二)东城区201222. ______ saw John at the shopping center last night. He said hello to us. A. We B. They C. He D. She 23. Peter is very tired, ______ he doesn’t want to go to bed. A. or B. but C. so D. and I wait here until three o’clock?24. — Must I wait here until three o’clock?— No, you ______.You can leave now. mustn’t C. can’t D. shouldn’t B. mustn’tneedn’t A. needn’t ______ money for the school trip. 25. Dave’s father gave him A. few B. many C. some D. any 26. ______ did you slow down? We are already late for the meeting. A. How B. When C. Why D. Where 27. The baby ______ a bottle of milk every morning. A. was drinking B. drinks C. drank D. is drinking 28. Of all the months in the year, December is ______. A. the coldest B. coldest C. colder D. cold 29. — What were you doing when the light went off? — I ______ with my sister on the phone. A. talk B. talked C. am talking D. was talking 30. Don’t disturb the professor. He is busy ______ his lessons. A. prepare B. prepares C. preparing D. to prepare 31. In the English class, I raised my hand and ______ the teacher a question. A. had asked B. have asked C. ask D. asked 32. Antony and Tom are good friends. They ______ each other for ten years. A. knew B. know C. have known D. had known 33. It took 16 years to build the Big Ben tower and it ______ in 1859. A. is finished B. was finished C. has finished D. had finished 34. — Could you tell me ______? — At 2:00. Hurry! There are only ten minutes left. A. what time we set off B. what time we will set off C. what time did we set off D. what time will we set off 五、完形填空(共12分,每小题1分)Four of my friends and I gathered at our favourite restaurant for Anna’s birthday party. We were all having a “Hey! Let’s go to 35 house and party on!”good time when suddenly Julia said, “I’m not sure if it’s a good idea,” I said. I looked to the others for support (支持), but it seemed they were 36 going to Julia’s house, for they didn’t know 37 to say “no” to Julia. Julia always tries to bully (欺负) But that didn’t the rest of us. She knew that we would all get into trouble with our parents if we left the restaurant. 38 her. “We should wait e should wait 39 Anna’s the birthday cake at 8:30,” I said“Don’t forget Anna’s mother will bring t he birthday cake at 8:30,” I said, “Wmother arrives!” “Don’t be silly. She’ll find us,” Julia said, laughing, like it was no big deal. ” I lied, not wanting to tell her I knew my mother wouldn’t 40 “My mother is coming here to pick me up,me to go. Then she began calling me names. “Stay here by yourself,” Julia said, “T he rest of us are going.”41 to I ran to the bathroom. I felt so childish, crying alone. It’s really I felt tears coming to my eyes, so go against your f riends, especially when you’re hoping to be popular with them. A moment later, Amanda came in“Julia is just that 42 . I agree with you. If we get out right now, maybe we can persuade (Julia is just that manda said as soon as we 43 45 44 . “If I leave o let’s take Susan’s 45 I was surprised it was so 46 . None of the girls left and I knew it was because Amanda sided with me. Holiday Activities for KidsClay Craft (陶艺)at Art CenterThis two-hour workshop teaches children to make gifts using clay. For children aged 6 to 12. When: Jul. 19 (1-3 pm) (Friday) Price: $20 Go to /clay for more information. Fun Cooking at Little Cook SchoolChildren aged 6 to 10 can learn to make healthy hamburgers. Children aged 10 to 12 can learn to make delicious cake. When: Every Wednesday (2-5 pm) in the month of Aug. Price: $35 Wonder Dance Class at Emma WorkshopLearn to dance with excellent teachers. A four-week dance course for those aged 10 to 12. When: Jul. 11 (3-5 pm) every Thursday Price: $60 for four lessons For details, go to . 47. Children can learn to make clay gifts on ______. A. Jul. 11 B. Jul. 19 C. Aug. 11 D. Aug. 19 48. At Emma Workshop, children can ______. A. have a big dinner B. make special gifts C. make hamburgers D. learn to dance 49. How many activities can an eight-year-old child take part in? A. 4. B. 3. C. 2. D. 1. BImagine you are walking to school when suddenly you notice a wallet in the street. After picking it up, you realize that it’s full of $10, $20, and $50 bills. They add up to $500! What would you do? Would you hand the wallet over to your headmaster as soon as you arrive at school? That’s just what Kemoy Gourzang did. “I have lost money before,” Kemoy, a 10-year-old boy, told the reporter, “I knew if I had lost my wallet, I would have wanted it back.”Joy-Ann Morgan, the headmaster, immediately called the owner of the wallet, using the ID inside. The man did not realize he had lost it. Morgan said he was happy to learn that an honest kid had found it. “This is what we want to teach our students,” Morgan explained. Kemoy has learned that doing the right thing pays off. His school district gave him a “GoodCitizen”Citizen” prize prize in honor of what he did. A person who has good citizenship is responsible and does the right thing. Kemoy has also received gifts from complete strangers, money, gift cards, and even a pair of sports shoes. As for the owner of the wallet, he thanked Kemoy when he went to the school to get his wallet back. He also gave the student $100 as a reward. “He told me I was the most honest person he had ever me I was the most honest person he had ever met,” Kemoy s aid, said, “It makes me really happy.” 50. How much money was there in the wallet? A. $10. B. $20. C. $50. D. $500. 51. What did Kemoy do after he picked the wallet up? A. He handed it over to the headmaster. B. He told his friends about the money. C. He called the owner of the wallet. D. He asked a reporter for help. 52. Kemoy received ______ for what he did from the school district. A. a pair of sports shoes A. a pair of sports shoes B. a gift card B. a gift card C. a “Good “Good “Good Ci Ci t izen”tizen”tizen” prize prize D. a $100 bill CWhat What do do do three three three hearts, hearts, hearts, eight eight eight arms, arms, arms, and and and one one one huge huge huge brain brain brain add add add up up up to? to? to? An An An octopus octopus —a a sea sea sea animal animal animal that that that can can can do do amazing things. Octopuses Octopuses are are are very very very smart. smart. smart. They They They can can can learn learn learn new new new things things things just just just like like like humans. humans. They’ve even learned a few skills to get themselves out of dangerous situations. Octopuses Octopuses don’t don’t don’t have have have teeth teeth teeth or or or sharp sharp (锋利的) ) claws claws claws to to to protect protect protect themselves. themselves. Instead, they use more clever ways to fool their enemies. Octopuses like to hide themselves in the sand on the bottom of the ocean floor. It can change the color of its skin to match the sand. And this color change happens in less than a minute. web, our new storehouse of information is just a click away. But this in no way has stolen the magic of reading’flutter (翻页) and their smell… You can lie in bed with a book, but with a books, the sound of their pagesinfluenced by whatever whatever they they they read. read. read. If If If inspirational inspirational inspirational stories stories stories and and and life life life experiences are read experiences are read in one ’s s teens, teens, teens, they they they can can change a person for the better. They stay with him and keep encouraging him to achieve his goals and choose the right against the wrong. The The more more more you you you read, read, read, the the the more more more creative creative creative and and and imaginative imaginative imaginative you you you will will will become. become. become. Reading Reading Reading develops develops develops vocabulary, vocabulary, improves language skills and sharpens your problem-solving abilities. It leads to a better understanding of self. Reading Reading gives gives gives you you you knowledge, knowledge, knowledge, it it it makes makes makes you you you more more more confident. confident. confident. The The The more more more you you you read read read about about about others’ others’ others’ lives lives lives and and experiences, a better decision-maker you will become. Reading about the importance of reading should lead you to read more, and more, and more. So choose a book you like and don’t stop reading until you reach the end . And even after that read as much as you can. 56. Which of the following is true? A. Children should start reading at a young age. B. Parents should tell their children stories every day. C. Teenagers should think and act differently from others. D. Students should find answers to their questions in books. 57. The underlined sentence in Paragraph 2 means ______. A. reading books is no longer a pleasure to people B. reading books is less interesting than reading online C. reading online can ’t take the place of reading books D. reading online can ’t be difficult for people 58. What can we infer from the passage? A. More teenagers read online now. B. What teenagers read builds their future. C. What children should learn first is phonics. D. More practice makes reading easier. 59. What’s the best title for the passage?A. Why Is Reading Important? B. What Should Teenagers Read? C. How Is Reading Ability Improved? D. When Should Children Start Reading? 七、阅读短文,根据短文内容,从短文后的五个选项中选出能填入空白处的最佳选项。
北京市东城区2012--2013学年第二学期初三综合练习(二) 数 学 试 卷 2013.6一、选择题(本题共32分,每小题4分) 1. 3的相反数是( ) A . 3-B .3C .13 D . 13-2. 太阳的半径大约是696 000千米,用科学记数法可表示为( )A .696×103千米 B .6.96×105千米 C .6.96×106千米 D .0.696×106千米 3.下列四个立体图形中,主视图为圆的是( )A B C D 4.已知在Rt △ABC 中,∠C =90°,∠A =α,AC =3,那么AB 的长为( ) A.3sin α B.3cos αC.αsin 3D.αcos 35. 抛掷一枚质地均匀的正方体骰子,骰子的六个面上分别刻有1到6的点数,掷得朝上一面的点数为3的倍数的概率为( ) A .16B .14C .13D .126. 若一个多边形的内角和等于720︒,则这个多边形的边数是( ) A .5B .6C .7D .87. 在一次中学生田径运动会上,参加男子跳高的15名运动员的成绩如下表所示:这些运动员跳高成绩的中位数和众数分别是( ) A .1.65,1.70 B .1.70,1.70C .1.70,1.65D .3,48. 如图,在平面直角坐标系中,已知⊙O 的半径为1,动直线AB 与x 轴交于点(,0)P x ,直线AB 与x 轴正方向夹角为45︒,若直线AB 与⊙O 有公共点,则x 的取值范围是( )A .11x -≤≤B .x <<C .0x ≤≤D .x ≤≤二、填空题(本题共16分,每小题4分) 9. 在函数23-=x y 中,自变量x 的取值范围是 . 10. 分解因式:244mn mn m ++= .11. 如图,已知正方形ABCD 的对角线长为ABCD 沿直线EF 折叠,则图中折成的4个阴影三角形的周长之和为 .12. 如图,∠ACD 是△ABC 的外角,ABC ∠的平分线与ACD ∠的平分线交于点1A ,1A BC ∠的平分线与1ACD ∠的平分线交于点2A ,…,1n A BC -∠的平分线与1n A CD -∠的平分线交于点n A . 设A θ∠=,则1A ∠= ;n A ∠= . 三、解答题(本题共30分,每小题5分)13. 计算:1012cos 45()(4-︒--π.14. 解分式方程:211322x x x--=--.15. 已知:如图,点E ,F 分别为□ABCD 的边BC ,AD 上的点,且12∠=∠. 求证:AE=CF .16. 已知2410x x -+=,求2(1)64x x x x-+--的值.17. 列方程或方程组解应用题:我国是一个淡水资源严重缺乏的国家,有关数据显示,中国人均淡水资源占有量仅为美国人均淡水资源占有量的15,中、美两国人均淡水资源占有量之和为13 800m 3,问中、美两国人均淡水资源占有量各为多少(单位:m 3)?18. 如图,一次函数1y x =--的图象与x 轴交于点A , 与y 轴交于点B ,与反比例函数ky x=图象的一个交点为M (﹣2,m ). (1)求反比例函数的解析式; (2)若点P 是反比例函数ky x=图象上一点,且2BOP AOB S S =△△,求点P 的坐标.四、解答题(本题共20分,每小题5分)19.某中学九(1)班同学为了解2013年某小区家庭月均用水情况,随机调查了该小区部分家庭,并将调查数据进行如下整理.请解答以下问题:(1)把上面的频数分布表和频数分布直方图补充完整;(2)求该小区用水量不超过15吨的家庭占被调查家庭总数的百分比;(3)若该小区有1000户家庭,根据调查数据估计,该小区月均用水量超过20吨的家庭大约有多少户?20.已知:如图,在菱形ABCD中,F为边BC的中点,DF与对角线AC交于点M,过M作ME⊥CD于点E. (1)求证:AM=2CM;∠=∠,CD=ME的值.(2)若1221.如图,点A ,B ,C 分别是⊙O 上的点,∠B =60°,AC =3,CD 是⊙O 的直径,P 是CD 延长线上的一点,且AP =AC .(1)求证:AP 是⊙O 的切线; (2)求PD 的长.22. 阅读并回答问题:数学课上,探讨角平分线的作法时,李老师用直尺和圆规作角平分线,方法如下:小聪只带了直角三角板,他发现利用三角板也可以作角平分线,方法如下:小颖的身边只有刻度尺,经过尝试,她发现利用刻度尺也可以作角平分线.根据以上情境,解决下列问题:(1) 小聪的作法正确吗?请说明理由;(2) 请你帮小颖设计用刻度尺作AOB ∠平分线的方法.(要求:不与小聪方法相同,请画出图形,并写出画图的方法,不必证明).五.解答题(本题共22分,第23题7分,第24题7分,第25题8分) 23. 已知:关于x 的一元二次方程01)2()1(2=--+-x m x m (m 为实数). (1)若方程有两个不相等的实数根,求m 的取值范围;(2)求证:抛物线1)2()1(2--+-=x m x m y 总过x 轴上的一个定点;(3)若m 是整数,且关于x 的一元二次方程01)2()1(2=--+-x m x m 有两个不相等的整数根时,把抛物线1)2()1(2--+-=x m x m y 向右平移3个单位长度,求平移后的解析式.24. 在矩形ABCD 中,4AB =,3BC =,E 是AB 边上一点,EF CE ⊥交AD 于点F ,过点E 作AEH BEC ∠=∠,交射线FD 于点H ,交射线CD 于点N .(1)如图1,当点H 与点F 重合时,求BE 的长;(2)如图2,当点H 在线段FD 上时,设BE x =,DN y =,求y 与x 之间的函数关系式,并写出自变量x 的取值范围;(3)连结AC ,当以点E ,F ,H 为顶点的三角形与△AEC 相似时,求线段DN 的长.25.定义:P,Q分别是两条线段a和b上任意一点,线段PQ长度的最小值叫做线段a与线段b的距离. 已知O(0,0),A(4,0),B(m,n),C(m+4,n)是平面直角坐标系中的四点.(1)根据上述定义,当m=2,n=2时,如图1,线段BC与线段OA的距离是_____;当m=5,n=2时,如图2,线段BC与线段OA的距离是______ .(2)如图3,若点B落在圆心为A,半径为2的圆上,求线段BC与线段OA的距离d.(3)当m的值变化时,动线段BC与线段OA的距离始终为2,若线段BC的中点为M,直接写出点M随线段BC运动所形成的图形的周长.北京市东城区2012--2013学年第二学期初三综合练习(二)数学试卷参考答案一、选择题(本题共32分,每小题4分)二、填空题(本题共16分,每小题4分)三、解答题:(本题共30分,每小题5分)13. 解:1012cos 45()(4π-︒--=2(4)214--- 分3=. ………5分14. 解:211322x x x -+=-- ………………1分 去分母得2113(2)x x -+=-解得6x =. ………………4分 经检验:6x =是原方程的根.所以原方程的根为6x =. ………………5分 15. 证明:∵四边形ABCD 是平行四边形,∴AB=CD ,∠B=∠D .…………………………2分 在△ABE 与△CDF 中,12.AB CD B D ∠=∠⎧⎪=⎨⎪∠=∠⎩,,∴△ABE ≌△CDF .…………………………4分 ∴AE=CF .………………………………5分16. 解:2(1)64x x x x-+-- 2(1)(4)(6)=(4)x x x x x x ---+-22424=4x x x x-+-2410x x -+= ,24=1x x ∴-- .22424124==23.41x x x x -+-+=---原式 ………………………………………5分17. 解:设中国人均淡水资源占有量为x m 3,美国人均淡水资源占有量为y m 3.根据题意得:5,13800.y x x y =⎧⎨+=⎩……………………………………………2分解得:2300,11500.x y =⎧⎨=⎩ ……………………………………………4分答:中、美两国人均淡水资源占有量各为2 300m 3,11 500m 3.………………………5分 18.解: (1) ∵M (﹣2,m )在一次函数1y x =--的图象上,∴ 211m =-=.∴ M (﹣2,1).又M (﹣2,1)在反比例函数ky x=图象上, ∴2k =-. ∴2y x-=. ……........................3分 (2)由一次函数1y x =--可求(10)A -,,(0,1)B -.∴11122112AOB S OB OA ∆=⨯⨯⨯=⨯=. ∴21=BOP AOB S ∆∆=.设BOP ∆边OB 上的高位h ,则=2h . 则P 点的横坐标为2±. 把P 点的横坐标为2±代入2y x-=可得P 点的纵坐标为1 . (2,1)P ∴-或(2,1)P -. ……5分四、解答题(本题共20分,每小题5分)19.解:(1) 表格:从上往下依次是:12,0.08;图略; ……3分 (2)68%;……4分 (3)120户. ……5分20.解:(1)∵四边形ABCD 是菱形.∴BC//AD .∴△∽△CFM ADM .∴CF CMAD AM=. ∵F 为边BC 的中点,∴1122CF BC AD ==. ∴12CF CM AD AM ==. ∴2AM MC =. ……………………2分 (2)∵A B//DC , ∴ 1=4∠∠. ∵1=2∠∠, ∴ 2=4∠∠. ∵ME ⊥CD , ∴12CE CD =. ∵四边形ABCD 是菱形, ∴ 3=4∠∠. ∵F 为边BC 的中点, ∴12CF BC =. CF CE ∴=.在△CMF 和△CME 中,3=4∠∠,CF =CE ,CM 为公共边,∴△CMF ≌△CME . ∴ =90CFM CEM ∠∠=︒. ∵2=34∠∠=∠, ∴2=3430∠∠=∠=︒.∴ME CE =∵2CD CE ==∴CE = ∴1ME =. ……………………………5分 21.解:(1)证明:连接OA .∵∠B =60°,∴∠AOC =2∠B =120°.又∵OA=OC ,∴∠ACP =∠CAO =30°.∴∠AOP =60°.∵AP=AC ,∴∠P =∠ACP =30°.∴∠OAP=90°,∴OA ⊥A P .∴ AP 是⊙O 的切线. …………………2分(2)解:连接AD .∵CD 是⊙O 的直径,∴∠CAD =90°.∴AD =AC •tan 30°=3 ∵∠ADC =∠B =60°,∴∠P AD =∠ADC ﹣∠P =60°﹣30°=30°.∴∠P =∠P AD .∴PD=AD …………………5分22.解: (1)小聪的作法正确. …………………1分理由:∵PM ⊥OM , PN ⊥ON ,∴∠OMP =∠ONP =90°.在Rt △OMP 和Rt △ONP 中,∵OP=OP , OM=ON ,∴Rt △OMP ≌R t △ONP (HL ).∴MOP NOP ∠=∠.∴OP 平分∠AOB . …………………2分(2)解:如图所示. …………………3分作法:①利用刻度尺在OA ,OB 上分别截取OG=OH .②连结GH ,利用刻度尺作出GH 的中点Q .③作射线OQ ,则OQ 为∠AOB 的平分线. …5分五.解答题(本题共22分,第23题7分,第24题7分,第25题8分)23.解:(1)22(2)4(1)m m m ∆=-+-=.∵方程有两个不相等的实数根,∴0≠m .……………………………………………………………………………1分 ∵01≠-m ,∴m 的取值范围是01m m ≠≠且.………………………………………………………2分(2)证明:令0=y 得,01)2()1(2=--+-x m x m .∴)1(2)2()1(2)2(2-±--=-±--=m m m m m m x . ∴1)1(221-=--+-=m m m x ,11)1(222-=-++-=m m m m x . …………………………………4分 ∴抛物线与x 轴的交点坐标为(0,1-),(0,11-m ).∴无论m 取何值,抛物线1)2()1(2--+-=x m x m y 总过定点(1,0-).……5分(3)∵1-=x 是整数 ∴只需11-m 是整数. ∵m 是整数,且01m m ≠≠且,∴2=m .…………………………………………………………………………6分 当2=m 时,抛物线为12-=x y .把它的图象向右平移3个单位长度,得到的抛物线解析式为861)3(22+-=--=x x x y .…………………………………………………7分24.解:(1)∵EF EC ⊥,∴90AEF BEC ∠+∠=︒.∵AEF BEC ∠=∠,∴45BEC ∠=︒.∵90B ∠=︒,∴BE BC =.∵3BC =,∴3BE =.…………………2分(2)过点E 作EG CN ⊥,垂足为点G .∴BE CG =.∵AB ∥CN ,∴AEH N ∠=∠,BEC ECN ∠=∠.∵AEH BEC ∠=∠,∴N ECN ∠=∠.∴EN EC =.∴22CN CG BE ==.∵BE x =,DN y =,4CD AB ==,∴()2423y x x =-≤≤.…………………4分(3)∵矩形ABCD ,∴90BAD ∠=︒.∴90AFE AEF ∠+∠=︒.∵EF EC ⊥ ,∴90AEF CEB ∠+∠=︒.∴AFE CEB ∠=∠.∴HFE AEC ∠=∠.当以点E ,F ,H 为顶点的三角形与AEC ∆相似时,ⅰ)若FHE EAC ∠=∠,∵BAD B ∠=∠,AEH BEC ∠=∠,∴FHE ECB ∠=∠ .∴EAC ECB ∠=∠.∴tan tan EAC ECB ∠=∠,∴BC BE AB BC =.∴94BE =.∴12DN =. ⅱ)若FHE ECA ∠=∠,如图所示,记EG 与AC 交于点O .∵AEH BEC ∠=∠,∴AHE BCE ∠=∠.∴ENC ECN ∠=∠.∵EN EC =,EG CN ⊥, ∴12∠=∠.∵AH ∥EG ,∴1FHE ∠=∠.∴2FHE ∠=∠.∴2ECA ∠=∠. ∴EO CO =.设3EO CO k ==,则4,5AE k AO k ==,∴85AO CO k +==. ∴58k =. ∴52AE =,32BE =. ∴1DN =. 综上所述,线段DN 的长为12或1. ………………7分25.解:(1)2 ………………4分(2)当24m ≤≤时,(22)d n n =-≤≤;当46m ≤≤时,2d =. ………………6分(3)16+4π. ………………8分。