专题强化测评(八) 1.3

2020-2021学年高中物理学业水平考试复习训练：演练测评专题八电磁现象与规律（选修1-1）合格演练测评(八)[电磁现象与规律（选修1－1）]姓名：__________班级:__________正确率：__________题号12345678910答案题号11121314151617181920答案一、单项选择题1．如图所示，将一束塑料包扎带一端打结，另一端撕成细条后，用手迅速捋细条，观察到细条散开了，则产生这种现象的原因是(）A．细条之间相互感应起电，相互排斥散开B．撕成细条后，所受重力减小,细条自然松散C．撕成细条后，由于空气浮力作用，细条散开D．由于摩擦起电，细条带同种电荷,相互排斥散开答案：D2．两个相同的金属小球M、N，带电量分别为－4q和＋2q。

两球接触后分开，M、N的带电量分别为()A．＋3q，－3q B．－2q，＋4qC．＋2q，－4q D．－q,－q答案:D3．关于静电的利用和防范，以下说法正确的是()A．没有安装避雷针的建筑物一定会被雷电击毁B．油罐车行驶途中车尾有一条铁链拖在地上，避免产生电火花引起爆炸C．飞机起落架的轮胎用绝缘橡胶制成，可防止静电积聚D．手术室的医生和护士都要穿绝缘性能良好的化纤制品，可防止麻醉药燃烧答案：B4．关于点电荷,下列说法中不正确的是()A．点电荷是一个带有电荷的几何点，它是实际带电体的抽象化，是一种理想化的模型B．点电荷自身不一定很小，所带电荷量不一定很少C．体积小于1 mm3的带电体就是点电荷D．体积大的带电体,只要满足一定的条件也可以看成点电荷答案:C5．真空中，距离为r，带电量均为q的两个点电荷间的库仑力大小为F.若将它们的电荷量都增大到2q，距离增大到2r，则它们之间的库仑力大小为(）A．错误!F B．FC．2F D．4F答案：B6．在光滑绝缘的水平面上，有两个相距较近的带同种电荷的小球，将它们由静止释放，则两球间（)A．距离变大,库仑力变大B．距离变大,库仑力变小C．距离变小，库仑力变大D．距离变小,库仑力变小答案：B7．关于电场线的以下说法中,正确的是(）A．电场线上每一点的切线方向都跟电荷在该点的受力方向相同B．沿电场线的方向，电场强度越来越小C．电场线越密的地方同一检验电荷受的电场力就越大D．顺着电场线移动电荷,电荷受电场力大小一定不变答案：C8．点电荷P、Q在真空中产生电场的电场线如图所示．下列说法正确的是()A．P、Q都是正电荷B．P、Q都是负电荷C．P是正电荷，Q是负电荷D．P是负电荷，Q是正电荷答案：D9．下列图中，绝缘细绳一端固定在O点，另一端系一个质量为m,带电量为＋q的小球．为了使小球能静止在图中所示位置，可以加一个与纸面平行的匀强电场，则所加电场方向符合要求的是（）答案：D10．下面关于电场的叙述不正确的是(）A．两个未接触的电荷发生了相互作用，一定是电场引起的B．只有电荷发生相互作用时才产生电场C．只要有电荷存在，其周围就存在电场D．A电荷受到B电荷的作用，是B电荷的电场对A电荷的作用答案：B11．下列是电场强度的单位的是(）A．库B．安C．牛/库D．伏答案:C12．如图所示是某静电场的一部分电场线分布情况，下列说法中正确的是()A．这个电场可能是负点电荷的电场B．点电荷q在A点处受到的电场力比在B点处受到的电场力大C．正电荷可以沿电场线由B点运动到C点D．点电荷q在A点处的瞬时加速度比在B点处的瞬时加速度小（不计重力)解析:负点电荷的电场线是从四周无限远处不同方向指向负点电荷的直线，故A错误；电场线越密的地方场强越大，由题图知E A〉E B，又因F＝qE，得F A>F B,故B正确;由a＝错误!知，a∝F,而F∝E，E A〉E B，所以a A>a B，故D错误；正电荷在B点受到的电场力的方向沿切线方向，故其轨道不可能沿曲线由B到C，故C错误．答案：B13．关于磁场和磁感线的描述,下列说法中正确的是()A．磁感线可以形象地描述各点磁场的强弱和方向,它每一点的切线方向都和小磁针放在该点静止时北极所指的方向一致B．磁极之间的相互作用是通过磁场发生的，磁场和电场一样，也是一种认为假想特殊物质C．磁感线总是从磁铁的北极出发,到南极终止D．磁感线就是细铁屑连成的曲线解析：磁场是一种客观存在的物质,磁极间的相互作用是通过磁场发生的．磁感线从N极出从S极入形成闭合曲线,A正确，B 错误，选项C、D错误;根据磁场方向的规定知选项A正确．答案：A14．下列关于磁感应强度的说法中不正确的是（)A．磁感应强度是矢量，用来表示磁场强弱和方向的物理量B．小磁针北极在磁场中受力的方向是唯一的,能比较客观地描述磁感应强度的方向C．磁极在磁场中受磁场力大的地方，该处的磁感应强度一定大D．磁极在磁场中受磁场力大的地方,该处的磁感应强度不一定大,与放置方向有关解析：关于磁感应强度的完整概念有以下内容:第一，是矢量，大小等于垂直穿过单位面积的磁通量，方向是小磁针北极在磁场中的受力方向；第二，物理意义，反映磁场强弱的物理量，从力的角度描述了磁场的性质，磁场强的地方放入磁极受到的力一定大;第三，单位是特斯拉，本题没有考查磁感应强度的单位．根据完整的物理概念，选项A、B、C正确．答案：D15．如图所示,与磁场方向垂直的线圈以OO′为轴旋转90°的过程中，穿过线圈的磁通量(）A．变大B．变小C．先变大后变小D．先变小后变大解析：设线圈转过的角度为θ，则线圈的磁通量Φ＝BS cos θ.在θ由0°增大到90°时，线圈的磁通量Φ逐渐减小,B正确．答案：B16．磁场中某区域的磁感线如下图所示，则（)A．a点磁场较强B．b点磁场较强C．两点的磁场一样强D．无法比较两点磁场的强弱解析：在磁场中,磁感线越密的地方，磁场越强,故b点磁场较强．答案：B17．在探究电磁感应现象的实验中，用导线将螺线管与灵敏电流计相连，构成闭合电路，如图所示，在下列情况中，灵敏电流计指针不会发生偏转的是（）A．磁铁放在螺线管里不动B．螺线管不动，将磁铁从螺线管中抽出C．螺线管不动，将磁铁向螺线管中插入D．磁铁不动，将螺线管上下移动解析:产生感应电流的条件是:闭合电路的磁通量变化,所以A选项符合题目要求．答案：A18．图为磁流体发电机的示意图,流体中的正、负离子均受到匀强磁场的作用，向M、N两金属极板运动．下列说法正确的是（）A．负离子向M极偏转B．正离子向M极偏转C．正、负离子均向N极偏转D．正、负离子均向M极偏转解析：根据左手定则可以判断正离子受洛伦兹力向下，负离子受洛伦兹力向上，因此正离子向N极偏转，负离子向M极偏转，故B、C、D错误，A正确．答案：A19．1927年，英国人在伦敦第一次用电传递了活动图象，标志着电视的诞生，通常电视信号通过电视塔发送，则电视塔天线发送的是（）A．电流B．电子C．电磁波D．声波解析:电视塔天线发送的是电磁波．答案:C20.如图所示，线圈与电流计组成闭合电路，下列情况中,电流计指针发生偏转的有（)A．磁铁置于线圈内不动B．线圈不动,磁铁向下移动C．线圈和磁铁保持相对静止，一起向上下移动D．线圈和磁铁保持相对静止,一起向左右移动解析:A项,磁铁置于线圈内不动,闭合回路的磁通量不发生变化，不会产生感应电流，电流计指针不会偏转，故A错误;B项，线圈不动，磁铁向下移动，闭合回路的磁通量发生变化，会产生感应电流，电流计指针会偏转，故B正确;C项，线圈和磁铁保持相对静止，一起向上下移动，闭合回路的磁通量不发生变化,不会产生感应电流，电流计指针不会偏转，故C错误；D项，线圈和磁铁保持相对静止，一起左右移动，闭合回路的磁通量不发生变化，不会产生感应电流，电流计指针不会偏转,故D错误．答案：B二、非选择题21．如图所示，螺线管中通有电流，如果在图中的a、b、c 三个位置上各放一个小磁针，其中a在螺线管内部，则（1)放在a处的小磁针的N极向______．(2)放在b处的小磁针的N极向______．（3)放在c处的小磁针的S极向______．(以上均填“左”或“右”)解析：由右手螺旋定则可知,螺线管右端是N极，左端为S极；因螺线管内部磁感线是由S极指向N极的，由于小磁针静止时N 极指向为磁场方向．因此小磁针a、b、c的N极都向右，故答案:右右右22．甲、乙两个带电粒子带电量分别为q和2q，运动速度分别为v和2v，当它们都进入到同一匀强磁场，且速度方向都与磁场方向垂直时，甲、乙受到的洛伦兹力大小之比为多少？解析:根据公式F＝qBv得,甲粒子受到的洛伦兹力F1＝qBv,乙粒子受到的洛伦兹力F2＝2qB·2v＝4qBv，所以甲乙受到的洛伦兹力之比为1∶4.答案:1∶423．一理想变压器原、副线圈匝数之比为2∶1,则原、副线圈的（1）电压之比为________(3)电流之比为________(3)功率之比为________(4)通过每匝线圈的磁通量比为________解析：电压比为错误!＝错误!＝错误!;电流比为错误!＝错误!＝错误!；功率比为1∶1;通过每匝线圈的磁通量之比为1∶1。

备考突破2020高三化学专题强化集训——溶度积常数的相关计算（精编解析）一、单选题（本大题共25小题，共50分）1.侯德榜是近代化学工业的奠基人之一，是世界制碱业的权威。

某同学在实验室模拟侯氏制碱法生产的纯碱中含有少量NaCl，下列说法正确的是A. 相同温度下，碳酸钙在纯碱溶液中的溶度积小于在水中的溶度积B. 用标准盐酸滴定一定质量的样品，可以测量出纯碱的纯度C. 用托盘天平称取样品配制溶液进行实验D. 只用硝酸银溶液，即可鉴别样品溶液中是否含有氯离子2.《环境科学》刊发了我国科研部门采用零价铁活化过硫酸钠，其中S为价去除废水中的正五价砷的研究成果，其反应机制模型如图所示。

设阿伏加德罗常数的值为，。

下列叙述正确的是A. 过硫酸钠含个过氧键B. 若参加反应，共有个被还原C. 室温下，中间产物溶于水所得饱和溶液中为D. pH越小，越有利于去除废水中的正五价砷3.常温下，用溶液分别滴定浓度均为的KCl、溶液，所得的沉淀溶解平衡图像如图所示不考虑的水解。

下列叙述正确的是A. 的数量级等于B. n点表示AgCl的不饱和溶液C. 向的混合液中滴入溶液时，先生成沉淀D. 的平衡常数为4.已知： 时，，。

下列说法正确的是A. 若向饱和溶液中加入固体，则有固体析出B. 反应的平衡常数C. 相同条件下，CuS在水中的溶解度大于在水中的溶解度D. 溶液中含固体，则溶液中的物质的量浓度为5.已知298K时下列物质的溶度积下列说法正确的是A. 等体积浓度均为的和溶液混合能产生沉淀B. 浓度均为的和混合溶液中慢慢滴入溶液时，先沉淀C. 在悬浊液中加入盐酸发生反应的离子方程式：D. 298K时，上述四种饱和溶液的物质的量浓度：6.设为阿伏加德罗常数的值，下列说法正确的是A. 时，的溶液中含有的数目为B. 的乙醇溶液中含氧原子C. 与过量氯气发生取代反应，生成气体为D. 时，则该温度下饱和溶液中含有个7.常温下，，，下列叙述不正确的是A. 浓度均为的溶液和NaCl溶液等体积混合，有白色沉淀产生B. 将的溶液滴入的KCl和的混合溶液中，先产生AgCl沉淀C. 的溶液中要产生沉淀，溶液的pH要控制在9以上D. 其他条件不变，向饱和水溶液中加入少量溶液，溶液中减小8. ，为研究用溶液将混合溶液中的和沉淀分离，绘制了 时AgCl和两种难溶化合物的溶解平衡曲线。

2021-2022学年八年级物理上册（人教版）第一章机械运动1.3运动的快慢同步练习（含答案）名师审核无超纲知识点习题·定向攻克适用于全国各市县人教版教材人教版八年级物理上册第一章机械运动1-3运动的快慢专题测评（2021-2022学年考试时间：90分钟，总分100分）班级：__________ 姓名：__________ 分数：__________一、单选题（每小题3分，共计45分）1、在龟、兔赛跑的情景中，关于比较她们俩运动快慢有如下几种说法①看台上的观众在比赛开始后，“观众”通过“相同时间比路程”的方法认为跑在前面的兔子运动快；②由于兔子自恃奔跑能力强，比赛途中睡了一觉，终点“裁判员”是通过“相同路程比时间”的方法来判定最先到达终点的乌龟运动得快；③物理学中是采用观众的方法比较乌龟与兔子的运动快慢程度；④物理学中是采用终点裁判员的方法比较乌龟与兔子运动快慢程度。

以上说法正确的是A．①②③ B．①②④ C．①④ D．②④2、在物理学中我们是以“单位时间内物体通过路程的多少”来描述物体运动快慢的，而在文学作品中常常用一些成语来描述物体运动的快慢，下面的成语中与物理学描述运动快慢的方法最相近的是（）A．一日千里 B．风弛电擎 C．离弦之箭 D．姗姗来迟3、通常一个人正常的步行速度约为A.10 m/sB.2 m/sC.60 km/hD.340 m/s4、一个运动物体在前2s内的平均速度是3m/s，后3s内的平均速度是5m/s，则它在5S内的平均速度是（）A．等于4m/s B．等于4.2m/s C．等于5m/s D．等于3m/s5、下列运动中的人或物，速度最大的是A．小明用5min，骑自行车前进了2000mB．刘翔110m栏赛跑的世界纪录是12秒88C．雨燕在空中10s的时间飞行250mD．铁路大提速后，“子弹头”列车的速度可达到250km／h6、小名和张伟进行百米赛跑，每次小名都要比张伟提前10m到达终点，若让小名将起点向后远离原起点10m,张伟仍在起点处与小名同时起跑，按原来的平均速度，则（）A、小名先到终点B、张伟先到终点C、两人同时到达终点D、条件不足，无法判断7、甲、乙两人同时从同一起跑线出发，同向做匀速直线运动，某时刻他们的位置如图所示，图4中能正确反映两人运动距离与时间关系的是8、你一定听说过《龟兔赛跑》的寓言故事吧！乌龟和兔子同时从起点跑出，兔子在远远超过乌龟后，便骄傲地睡大觉。

八年级数学重点题型强化训练5——线段垂直平分线专题第1题第2题【分析】本题考查的是线段垂直平分线的性质：熟记：线段垂直平分线上的点到这条线段两个端点的距离第3题可证BEF CED ≌△△，可得EF =BC 的中点，第5题第6题第7题第8题 第9题【答案】B 【分析】利用全等三角形的判定以及垂直平分线的性质得出OBC Ð，以及40，OBC OCB Ð=Ð=°，再利用翻折变换的性质得出，CEF FEO =Ð进而求出即可．50，BAC BAC Ð=°ÐQ 12OAB CAO \Ð=Ð=25OAB ABO Ð=Ð=∵在等腰ABC V 中，DG Q 是BC 的垂直平分线，BD CD \=，AD Q 是BAC Ð的平分线，DE DF \=，在Rt BDE △和Rt CDF △中，C ．60°D 【分析】先根据线段垂直平分线的性质得到BE CE =，则AC EC =，再根据等腰三角形的性质和三角形内，接着利用三角形外角性质计算出EBC Ð=Ð的度数．故选：C ．题型2：线段垂直平分线的判定11．如图，AD AC =，BD BC =，则下列判断一定正确的是（ ）A ．AB 垂直平分CDB ．CD 垂直平分ABC ．CD 平分ACB ÐD ．以上都不正确第11题第12题【答案】A【分析】根据线段垂直平分线的判定求解即可．【详解】解：∵AD AC =，BD BC =，∴点A 、B 在线段CD 的垂直平分线上，即AB 垂直平分CD ，故选：A ．12．如图，ABC AB AC BC >>V ，，边AB 上存在一点P ，使得PA PC AB +=．下列描述正确的是（ ）A ．P 是AC 的垂直平分线与AB 的交点B ．P 是ACB Ð的平分线与AB 的交点C ．P 是BC 的垂直平分线与AB 的交点D ．P 是AB 的中点【答案】C【分析】根据线段垂直平分线的判定解答即可．【详解】解：PA PC AB PA BP AB +=+=Q ，，PC BP \=，∴P 是BC 的垂直平分线与AB 的交点．故选：C ．13．如图，将长方形纸片沿AC 折叠后点B 落在点E 处，则下列关于线段BE 与AC 的关系描述正确的是（ ）A ．AC BE =B ．AC 和BE 相互垂直平分C ．AC BE ^且AC BE=D ．AC BE ^且AC 平分BE【答案】D 【分析】只要证明AC 是线段BE 的垂直平分线即可解决问题．【详解】解：ACE QV 是由ACB △翻折得到，AE AB \=，CB CE =，AC EB \^，AC 平分EB ，故选：D ．14．如图，已知：AB AC =，MB MC =．求证：直线AM 是线段BC 的垂直平分线．下面是小彬的证明过程，则正确的选项是（ ）证明：∵AB AC=∴点A 在线段BC 的垂直平分线上①∵MB MC=∴点M 在线段BC 的垂直平分线上②∴直线AM 是线段BC 的垂直平分线③A ．①处的依据是：线段垂直平分线上的点与这条线段两个端点的距离相等B ．②处的依据是：与线段两个端点距离相等的点在这条线段的垂直平分线上C ．③处的依据是：与线段两个端点距离相等的点在这条线段的垂直平分线上D ．以上说法都不对【答案】B【分析】根据垂直平分线的判定方法逐项判断即可．【详解】解：①处的依据是：与线段两个端点距离相等的点在这条线段的垂直平分线上，故A 选项错误，不合题意；②处的依据是：与线段两个端点距离相等的点在这条线段的垂直平分线上，故B 选项正确，符合题意；③处的依据是：两点确定一条直线；故C 选项错误，不合题意；综上可知，选项D 错误，不合题意；故选B ．15．下列说法错误的是（ ）A ．若点P 是线段AB 的垂直平分线上的点，则PA PB=B ．若PA PB =，QA QB =，则直线PQ 是线段AB 的垂直平分线C ．若PA PB =，则点P 在线段AB 的垂直平分线上D ．若PA PB =，则过点P 的直线是线段AB 的垂直平分线【答案】D【分析】根据线段垂直平分线的判定方法，即可一一判定．【详解】解：A.若点P 是线段AB 的垂直平分线上的点，则PA PB =，故该说法正确，不符合题意；B.若PA PB =，QA QB =，则直线PQ 是线段AB 的垂直平分线，故该说法正确，不符合题意；C.若PA PB =，则点P 在线段AB 的垂直平分线上，故该说法正确，不符合题意；D.若PA PB =，则过点P 的直线不一定是线段AB 的垂直平分线，故该说法错误，符合题意；故选：D ．16．如图，AD 是ABC V 的角平分线，交BC 于D ，DE DF 、分别是ABD △和ACD V 的高，分别交AB AC 、于E 、F ，连接EF 交AD 于G ．下列结论：①AD 垂直平分EF ；②EF 垂直平分AD ；③AED AFD V V ≌；④当BAC Ð为60°时，AEF △是等边三角形，其中正确的结论的个数为（ ）A ．4个B ．3个C ．2个D ．1个第16题第17题【答案】B 【分析】根据角平分线性质求出DE DF =，证AED AFD V V ≌，推出AE AF =，再逐个判断即可．【详解】解：∵AD 是ABC V 的角平分线，DE DF 、分别是ABD △和ACD V 的高，∴DE DF =，90AED AFD Ð=Ð=°，在Rt AED △和Rt AFD △中，AD AD DE DF =ìí=î，∴()Rt Rt HL AED AFD ≌△△，故③正确；∴AE AF =，∴AD 垂直平分EF ，①正确；②错误；∵60BAC Ð=°，且AE AF =，∴AEF △是等边三角形，④正确．综上，①③④正确，共3个．故选：B ．17．如图，在△ABC 中，AD 是△ABC 的角平分线，点E 、F 分别是AD 、AB 上的动点，若∠BAC ＝50°，当BE +EF 的值最小时，∠AEB 的度数为（ ）A ．105°B ．115°C ．120°D ．130°【答案】B【分析】过点B 作BB ′⊥AD 于点G ，交AC 于点B ′，过点B ′作B ′F ′⊥AB 于点F ′，与AD 交于点E ′，连接BE ′，证明AD 垂直平分BB ′，推出BE ＝BE ′，由三角形三边关系可知，BE EF B E EF B F B F ¢¢¢¢+=+³³，即BE +EF 的值最小为B F ¢¢，通过证明△ABE ′≌△AB ′E ′，推出∠AE ′B ＝AE ′B ′，因此利用三角形外角的性质求出AE ′B ′即可．【详解】解：过点B 作BB ′⊥AD 于点G ，交AC 于点B ′，过点B ′作B ′F ′⊥AB 于点F ′，与AD 交于点E ′，连接BE ′，如图：此时BE +EF 最小．∵AD 是△ABC 的角平分线，∠BAC ＝50°，∴∠BAD ＝∠B ′AD ＝25°，∵BB ′⊥AD ，∴∠AGB ＝∠AGB ′＝90°，在△ABG 和△AB ′G 中，BAG B AG AG AGAGB AGB Ð=Ðìï=íïТ=Ðî¢，∴△ABG ≌△AB ′G （ASA ），∴BG ＝B ′G ， AB ＝AB ′，∴AD 垂直平分BB ′，∴BE ＝BE ′，在△ABE ′和△AB ′E ′中，BE BE AE AE AB AB ¢¢¢¢ìï=íï=î＝，∴△ABE ′≌△AB ′E ′（SSS ），∴∠AE ′B ＝AE ′B ′，∵AE ′B ′＝∠BAD + AF ′E ′＝25°+90°=115°，∴∠AE ′B ＝115°．即当BE +EF 的值最小时，∠AEB 的度数为115°．故选B ．18．如图，点P 是AOB Ð内的一点，PC OA ^于点C ，PD OB ^于点D ，连接OP ，CD ．若PC PD =，则下列结论不一定成立的是（ ）A ．AOP BOPÐ=ÐB ．OPC OPD Ð=ÐC ．PO 垂直平分CD D ．PD CD=【答案】D【分析】根据角平线的判定定理可判断A ，证明Rt COP Rt DOP V V ≌，可判断B ，根据Rt COP Rt DOP V V ≌，可得OC =OD ，进而可判断C ，根据等边三角形的定义，可判断D ．【详解】解：∵点P 是AOB Ð内的一点，PC OA ^于点C ，PD OB ^于点D ，PC PD =，∴OP 是∠AOB 的平分线，即AOP BOP Ð=Ð，故A 成立，不符合题意；∵OP =OP ，AOP BOP Ð=Ð，第19第20题=，利用ASA Ð，再根据E是CD的中点可求出ECECF=，结合已知可得BE的垂直平分线，根据线段垂直AE EF=+，进而即可求解．即可证得AB BC AD故答案为：70．题型3：与线段垂直平分线相关的尺规作图21．如图，在ABC V 直线MN ，交BC A ．9【答案】B 【分析】由题意可得MN ADC C AC BC =+V ，求解即可．【详解】解：由题意可得，A．3B 【答案】B【分析】利用基本作图得到V的周长为20再利用ABC【详解】解：由作法得DE \==，,DA DB AE BEA ．①③B ．①④C ．②④D ．③④【答案】B 【分析】依次对各个图形的作图痕迹进行分析即可．【详解】 由图①知AD AC =，AB AD >，AB AC \>，故图①能说明AB AC >；由图②知射线BD 是ABC Ð的平分线，不能说明AB AC >；由图③知CD AB ^，不能说明AB AC >；由图④知DE 是BC 的垂直平分线，DB DC \=．ADC QV 中AD DC AC +>，AD DB AC \+>，即AB AC >．故图④能说明AB AC >．故选：B24．如图所示，在Rt ABC △中，90C Ð=°，以B 为圆心，以任意长度为半径作弧，与BA ，BC 分别交于A．20°B．36【答案】C【分析】由作图可知：BO为=，再根据等腰三角形的性质得AD BD和定理即可求出AÐ的度数．【详解】解：由作图可知：平分EAC Ð；③AC CD =；④ABC S V C ．①③DA ．只有甲的答案正确B ．甲和乙的答案合在一起才正确C ．甲和丙的答案合在一起才正确D ．甲乙丙的答案合在一起才正确【答案】D 【分析】分四种情况讨论：当APB Ð为锐角时，当APB Ð为钝角时，当APB Ð为直角时，当135APB Ð=°时，分别画出图形，求出x 与y 的关系，即可得出答案．【详解】解：当APB Ð为锐角时，如图所示：∵AD BP ^，∴90ADP Ð=°，∴90PAD APD Ð+Ð=°，即90x y +=；当APB Ð为钝角时，如图所示：∵AD BP ^，∴90ADP Ð=°，∵APB Ð为ADP △的外角，∴APB ADP DAP Ð=Ð+Ð，∴90x y =+，即90x y -=；当APB Ð为直角时，如图所示：此时直线n 与PA 重合，∴此时直线n 与PA 所夹的角为0°，即90x y +=或90x y -=；当135APB Ð=°时，如图所示：18013545DPA Ð=°-°=°，∵AD BP ^，∴90ADP Ð=°，∴904545DAP Ð=°-°=°，∴45135180DAP APB Ð+Ð=°+°=即180x y +=；1AB 的长为半径作弧，两弧相交于AM ；的长为半径作弧，与BC 边相交于点N ，连接C．9AC，根据中垂线的定义和性质找到相等的边，进而由AC，A ．15B ．16C ．18D ．20【答案】A 【分析】根据题意得到MN 是线段AB 的垂直平分线，进而得到点D 是AB 的中点，根据三角形的面积公式计算，得到答案．【详解】解：由尺规作图可知，MN 是线段AB 的垂直平分线，\点D 是AB 的中点，ACD BCD S S \=△△，ADE CDE CDB S S S \+=V V V ，Q CDB △的面积为12，ADE V 的面积为9，1293CDE CDB ADE S S S \=-=-=V V V ，\四边形EDBC 的面积为：12315CDE CDB EDBC S S S =+=+=V V 四边形，故选：A ．30．如图，在ABC V 中，根据尺规作图痕迹，下列说法不一定正确的是（ ）．A ．AF BF=B ．90AFD FBC Ð+Ð=°C ．DF AB^D ．BAF CAFÐ=Ð【答案】D 【分析】由图中尺规作图痕迹可知，BE 为ABC Ð的平分线，DF 为线段AB 的垂直平分线，结合角平分线的定义和垂直平分线的性质逐项分析即可．【详解】解：由图中尺规作图痕迹可知， BE 为ABC Ð的平分线，DF 为线段AB 的垂直平分线．上求作点D ，使；，若点D 在边上，在上求作点E ，使．）作BC 的垂直平分线与BC 的交点即为所求；）如图：由题意得，只要作12BDE ABC S S △△=即可，由第（1）问得，12ABP ABC S S △△=，只要作BC ABD ACD S S =V V AB BC BDE ADEC S S △四边形=作BC 的垂直平分线与BC 交于D 点，BD CD \=，ABD QV 与ACD V 高相同，ABD ACD S S \=V V ．如图1：点D 即为所求；（2）如图：由题意得，只要作12BDE ABC S S △△=即可，作BC 的垂直平分线交BC 于P 点，由第（1）问得，12ABP ABC S S △△=，故只要作BDE ABP S S △△=即可，连接D 、P ，要使得BDE ABP S S △△=，只要作根据“夹在平行线之间的垂线段相等”，即，高相等，如图2：点E 即为所求．32．如图，在中，点E 在上且．(1)请用尺规作图的方法在边上确定点D ，使得；（保留作图痕迹，不写作法）(2)在（1）的条件下，若的周长为，求的长．【分析】（1）线段AB 的垂直平分线与BC 边的交点即为所求；（2）根据线段垂直平分线的性质，通过等量代换求解．【详解】（1）解：如图所示，线段AB 的垂直平分线与BC 边交于点D ，点D 即为所求；（2）解：Q ADE V 的周长为12cm ，\12AD AE DE ++=，Q BD AD =，AE CE =，\12BC BD CE DE AD AE DE =++=++=，即BC 的长为12cm ．题型4：与线段垂直平分线相关的计算与证明33．如图，在ABC V 中，AB 、AC 边的垂直平分线相交于点O ，分别交BC 边于点M 、N ，连接AM ，AN ．(1)若AMN V 的周长为6，求BC 的长；(2)若30B Ð=°，25C Ð=°，求MAN Ð的度数；(3)若MON a Ð=，请用a 表示MAN Ð的度数（直接写出即可）．ABC V BC AE CE =BC BD AD =ADE V 12cm BC【答案】(1)6(2)70°(3)1802MAN aÐ=°-【分析】（1）由垂直平分线的性质可得,AM BM AN CN ==，再由BC AM MN AN =++可得结论；（2）由垂直平分线的性质可得30,30,B BAM C CAN Ð=Ð=°Ð=Ð=°，再根据三角形内角和定理可得结论；（3）根据三角形内角和定理可得()1802MAN B C Ð=°-Ð+Ð，再由四边形内角和定理可得180B C MAN O Ð+Ð=°-Ð-Ð，代入求解即可【详解】（1）,OM ON Q 分别是AB 、AC 边的垂直平分线，,,AM BM AN CN \==6AM MN AN ++=Q 6BM MN CN \++=，即6BC =（2）,,AM BM AN CN ==Q 30,25,BAM B CAN C \Ð=Ð=°Ð=Ð=°180,B BAC C Ð+Ð+Ð=°Q 且BAC BAM MAN CANÐ=Ð+Ð+Ð180,B BAM MAN CANC \Ð+Ð+Ð+Ð+Ð=°即180,B B MANC C Ð+Ð+Ð+Ð+Ð=°18022180605070MAN B C \Ð=°-Ð-Ð=°-°-°=°（3）如图，180,B BAC C Ð+Ð+Ð=°Q 且BAC BAM MAN CAN Ð=Ð+Ð+Ð180,B BAM MAN CANC \Ð+Ð+Ð+Ð+Ð=°即180,B B MANC C Ð+Ð+Ð+Ð+Ð=°()1802MAN B C \Ð=°-Ð+Ð,,OM ON Q 分别是AB 、AC 边的垂直平分线，90AEO AFO \Ð=Ð=360AEO EAF AFO FOE \Ð+Ð+Ð+Ð=°180EAF O \Ð+Ð=°180,BAF MAN CAN O \Ð+Ð+Ð+Ð=°180,B C MAN O \Ð+Ð+Ð+Ð=°180B C MAN O\Ð+Ð=°-Ð-Ð()()180********MAN B C MAN O \Ð=°-Ð+Ð=°-°-Ð-Ð\解得，1802MAN aÐ=°-34．如图，在Rt ABC △中，45,90,ACB BAC AB AC Ð=°Ð=°=，点D 是AB 的中点，AF CD ^于H 交BC 于F ，BE AC ∥交AF 的延长线于E ．求证：BC 垂直且平分DE ．【答案】见解析【分析】根据全等三角形的判定证明(ASA)ABE CAD ≌V V ，在再证明(SAS)DBP EBP ≌V V 即可解决问题；【详解】证明：由题意可知，9090DAH ADH ACH ADH ÐÐÐÐ+=°+=°，，∴DAH ACH ÐÐ=，∵90BAC Ð=°，BE AC ∥，∴90CAD ABE ÐÐ==°．又∵AB CA =，∴在ABE V 与CAD V 中，DAH ACH AB AC CAD ABE Ð=Ðìï=íïÐ=Ðî，∴(ASA)ABE CAD ≌V V ．∴AD BE =，又∵AD BD =，∴BD BE =，在Rt ABC V 中，45,90,ACB BAC AB AC ÐÐ=°=°=，故45ABC Ð=°．∵90ABE Ð=°，∴904545EBF Ð=°-°=°，∴(SAS)DBP EBP ≌V V ，∴DP EP =，∴BC 垂直且平分DE ．35．如图，ABC V 中，AD 平分BAG Ð，DG 垂直平分BC ，DE AB ^于E ，DF AC ^于F ．(1)求证：BE CF =；(2)如果9AB =，5AC =，求BE 的长．【答案】(1)见解析；(2)2BE =．【分析】（1）由DG 垂直平分BC 可得DB DC =，由AD 平分BAG Ð， DE AB ^，DF AC ^，可得DE DF =，90DEB DFC Ð=Ð=°，从而证得()Rt Rt HL DBE DCF V V ≌，得证BE CF =；（2）易证()Rt Rt HL ADE ADF ≌△△，得到AE AF =，又BE CF =，因此2AB AE BE AF BE AC CF AC BE =+=+=+=+，代入即可解答．【详解】（1）连接DB ，DC ，∵DG 垂直平分BC ，∴DB DC =，∵AD 平分BAG Ð，DE AB ^，DF AC ^，∴DE DF =，90DEB DFC Ð=Ð=°，∴在Rt DBE V 和Rt DCF V 中DB DC DE DF=ìí=î∴()Rt Rt HL DBE DCF V V ≌，∴BE CF =．（2）∵DE AB ^，DF AC ^，∴在Rt ADE △和Rt ADF V 中AD AD DE DF=ìí=î∴()Rt Rt HL ADE ADF ≌△△，∴AE AF=∵BE CF=∴2AB AE BE AF BE AC CF AC BE =+=+=+=+，∵9AB =，5AC =，∴952BE =+，∴2BE =．36．如图，AB AC ＞，BAC Ð的平分线与BC 边的垂直平分线GD 相交于点D ，过点D 作DE AB ^于点E ，DF AC ^于点F ，求证：BE CF =．【答案】见解析【分析】连接DC ，根据GD 是BC 边的垂直平分线，得到DC DB =，根据AD 是BAC Ð的平分线，且DE AB ^，DF AC ^，得到DE DF =，根据DE DF DB DC =ìí=î，得到()HL DEB DFC V V ≌即可得证．【详解】如图，连接DC ，∵GD 是BC 边的垂直平分线，∴DC DB =，∵AD 是BAC Ð的平分线，且DE AB ^，DF AC ^，∴DE DF =，∵DE DF DB DC =ìí=î，∴()HL DEB DFC V V ≌∴BE CF =．37．如图，在ABC V 中，BAC Ð的平分线与BC 的中垂线DE 交于点E ，过点E 作AC 边的垂线，垂足N ，过点E 作AB 延长线的垂线，垂足为M ．(1)求证：BM CN =；(2)若2AB =，8AC =，求BM 的长．【分析】（1）连接BE ，CE ，由题意易得BE CE =，EM EN =，进而可证Rt Rt BME CNE ≌V V ，然后问题得解；（2）由（1）得：EM EN =，进而可证Rt Rt AME ANE ≌V V ，则有AB BM AC CN +=-，然后根据线段的和差关系可求解．【详解】（1）证明：连接BE ，CE ，DE Q 是BC 的垂直平分线，BE CE \=，AE Q 是BAC Ð的平分线，EM AB ^，EN AC ^，EM EN \=，在Rt BME △和Rt CNE △中，BE CE EM EN=ìí=î()Rt Rt BME CNE HL \V V ≌，BM CN \=；（2）由（1）得：EM EN =，在Rt AME △和Rt ANE △中，AE AE EM EN=ìí=îRt Rt AME ANE \≌V V ，请根据所给教材内容，结合图①，写出“线段垂直平分线的性质定理”完整的证明过程．定理应用：V中，AB、AC的垂直平分线分别交BC于点D、E，垂足分别为M，N，已知）如图②，在ABC的周长为20，则BC的长为__________．∵AB AC AD BC ^=，，的周长为7，可得∴19712AB BE +=-=，∴6AB BE ==；（2）∵30ABC Ð=°，45C Ð=°，∴1803045105BAC Ð=°-°-°=°，在BAD V 和BED V 中，BA BE BD BD DA DE =ìï=íï=î，∴()SSS BAD BED V V ≌，∴105BED BAC Ð=Ð=°，∴1054560CDE BED C Ð=Ð-Ð=°-°=°．40．如图，在ABC V 中，点E 在AB 上，点D 在BC 上，BD BE =，BAD BCE Ð=Ð，AD 与CE 相交于F ．(1)求证：AF CF =；(2)连接，试判断与的位置关系，并说明理由．【分析】（1）根据全等三角形的判定与性质，可得BA BC =，BDA BEC Ð=Ð，根据补角的性质，可得FDC FEA Ð=Ð，根据全等三角形的判定与性质，可得答案．（2）由AB CB =，AF CF =可得点B ，F 在AC 的垂直平分线，即可得出结论【详解】（1）在BAD V 和BCE V 中，∵B B BAD BCE BD BE Ð=ÐìïÐ=Ðíï=î，∴BAD V ≌BCE V ，∴AB CB =，BF BF AC与点A 重合，则 ， ．，四边形的直角沿直线l 折叠后（如图2），点B 落在四边形的边与AB 相交于点F ，猜想OF 、EF 、AB 三者数量关系，并证明．若折叠后点D 恰为AB 的中点（如图3），求的度数；45°，8数量关系为：AB OF EF =+；证明见解析q ==a OABC OCB ÐOABC q∴E O D FO D Ð=Ð．由折叠可得FOD EOC EOD q Ð=Ð=Ð=，∴390COA q Ð==°，∴30q =°．。

专题08 综合性学习阅读一、常见考题类型1、劝说例：王华的爸爸反对他阅读文学名著，理由是“那都是闲书，没什么用”。

王华请求你帮助他说服家长。

把你要说的话写在下面。

解析：在我们的日常生活中，我们常常希望把自己的观点、想法或思路准确有效地传达给他人，并且希望对方能够接受我们的意见或建议，然后付诸实施，这个过程就是说服。

既然要说服他人，就不能把自己的观点强加给对方。

这就必须晓之以理、动之以情，以理服人、以情动人，让对方心服口服。

答案示例：叔叔，文学名著是人类智慧的结晶。

阅读文学名著，可以增长知识，丰富情感，提升文化品位。

成长，是离不开文学名著的滋养的。

老师还鼓励我们读名著呢。

希望您你能同意王华业余时间读名著。

2、邀请例：4月23日，是“世界读书日”，班里准备在这天下午3点，在本班教室开展关于读书的主题班会活动。

4月22日下午，你去邀请语文老师参加这次班会活动。

请你将对语文王老师说的话写在下面。

解析：既然是邀请他人，所以首先一定要说明邀请对方参加什么活动，邀请的原因是什么。

其次是要将活动安排的相关细节及注意事项告诉对方，诸如时间、地点、参加人员，做些什么样的准备等。

答案示例：王老师，明天下午3点，我们班在教室里开读书主题班会，请您到现场指导。

3、谢绝例：张林到外地读书近一年了，回家后去看望大姑，大姑非常热情地留他吃午饭，张林认为时间还早，还要去看二姑，不想在大姑家吃午饭，张林应该怎样谢绝大姑的挽留呢?如果你是张林，你会怎么说?解析：答这类题要讲清原委，求得对方的谅解，注意语气要委婉。

答案示例：张林说：大姑，一年不见，我非常想在大姑家多玩一些时间，只是时间还早，我还要去看望二姑，我也很想念她，谢谢大姑，过两天我再来，好吗?4、拒绝例：2012年3月28日国务院第197次常务会议通过，并公布施行《校车安全管理条例》。

司机小王正是这天开始驾驶校车接学生上学的。

现在，校车按规定已经满员了，可是一位学生家长却强行搭车去超市购买生活用品。

阅读理解专题强化训练——人教版八年级下册期末考前必备【练习1】It’s important for us to keep healthy. But in fact, many people have health problems. Many people fall ill and many children become heavier.As we grow older, we experience many life changes, such as job changes, children leaving home and physical (身体的) changes. How we grow from these changes is the key to staying healthy.These ways can help us keep our physical and emotional (情绪的) health. First, we must keep away from smoking and drinking. Second, we should do exercise every day. We can walk to school instead of taking a bus or a car. Third, we shouldn’t eat too much fast food. We can eat more fruit and vegetables.Many studies show that people always feel better when they’re with friends than when they’re alone. So be sure to make some friends.Staying healthy is important at any age and that doesn’t change just because we have a few more white hairs.1. The writer mainly tells us ______ has something to do with our health.A. what we likeB. what we experienceC. how we go to schoolD. how we look2. From the second paragraph, we can know if we want to keep healthy we must learn to face ______.A. life changesB. health problemsC. food problemsD. exercise problems3. The writer tells us ______ are the ways to stay healthy in the third paragraph.A. eating more fruit and doing exerciseB. stopping smoking and drinkingC. exercise and good eating habitsD. A, B and C4. If we want to feel better, we can______.A. see doctors oftenB. exercise more and drink lessC. keep our life fullD. make more friends5. The passage mainly tells us______.A. how to keep physical and emotional healthB. three ways to stay thinC. how to feel wellD. staying healthy is very important1-2 DBADD【练习2】Medical experts say most Americans do not get enough sleep. They say more Americans need to take a nap—that is to rest for a short period in the middle of the day. They give people advice to sleep lightly before continuing with other activities. The experts say naps might improve health by reducing pressure.Some European and Latin American companies have supported the idea of napping for many years. They ask people to leave work, go home and have a nap before returning. In the United States, some companies let workers rest simply in their offices. They believe this can help workers make fewer mistakes and also increase the amount of work that a person can do.Sleep experts say it is likely that people make more mistakes at work than at other times. They say people should not carry out important tasks when they feel sleepy. And they say the best thing to do is to take a nap. About twenty minutes of rest is all you need. Experts say this provides extra energy and can increase your effects until the end of the day. But experts said that a nap should last no more than twenty to thirty minutes. A longer nap will put the body into deep sleep and waking up will be difficult.1. This passage is probably taken from ___________.A. a story bookB. a posterC. a science fictionD. medical magazine2. What’s the best way to increase workers’ effects?A. Talking with friends.B. Doing relaxing exercises.C. Laughing, smiling and crying.D. Having a rest for twenty or thirty minutes.3. What will happen to the workers if they keep on working without any rest?A. They will get a lot of money.B. They will fail in their jobs and even cause a lot of trouble.C. They will live a happy life in the future.D. They will feel better after finishing everyday jobs.4. The meaning of the underlined word “reducing” in the first paragraph is “______A. 加大B. 缓解C. 产生D. 制造5. The passage mainly talks about____________.A. taking a nap during the dayB. the disadvantages of taking a napC. Americans who don’t have a nap during the weekendsD. the advantages of deep sleep1-5 ADDBB【练习3】Many of us don’t pay much attention to the importance of eye care. It is said that if you take care of your body, then you can surely be healthy. That is why our eyes should be given a lot of care. Natural eye care should be put in a number one place.There are several causes leading to poor eyesight like not enough food, genes (基因) and aging (老化). Televisions, computers and reading are also the causes of having poor eyesight. If you happen to work in front of the computer, it is best to take a break every once in a while.Something dirty can cause redness and they will make you feel uncomfortable. It is bad for your eyes too. If this happens, the best way is to clean your eyes by using cold water. You must also try your best to protect your eyes from harmful things. For example, sunglasses are not just for fashion but they can also serve as a great way to protect your eyesight from UVrays.Eating healthy foods will do good to your eyesight. Remember that vitamins A, C and E are good for eyes. Try to eat food groups that have these vitamins. And you should do eye exercises because exercise protects your eyesight too. If a person exercises regularly (定期地) and eats the right kind of food, his eyes will stay in good condition for a long time.All above are natural ways of eye care that help us keep healthy eyes. Being happy all the time can be helpful to a person’s eyesight, too. In a word, eye care is very important, no matter how old a person is.1. ___________ is the most important way to protect our eyes.A. Taking medicineB. Natural eye careC. Seeing the doctorD. Being happy all the time2. What should you do if you have to work in front of the computer?A. Having a rest after working for a while.B. Eat healthy foods.C. Clean the eyes by using cold water.D. Wear a pair of sunglasses.3. What do the underlined words “UV rays” mean?A. 闪电B. 沙尘C. 紫外线D. 超声波4. Which is the best title of the passage?A. Ways of Eye ExercisesB. Ways of Eye CareC. Ways of Being HappyD. Ways of Being Healthy1-4 BACB【练习4】Early to bed, early to rise, makes a man healthy, wealthy and wise. This is an old English saying. Have you heard of it before? It means that we must go to bed early and get up early in the morning. Then we shall be healthy. We shall also be rich (wealthy) and clever (wise).This is true. The body must have enough sleep to be healthy. Children of young age should have ten hours’ sleep every night. Children who do not have enough sleep cannot do their work very well. They will not be wise and they may not become wealthy!The body also needs exercise. Walking, running, jumping, swimming and playing games are all exercise. Exercise keeps the body strong. Exercise also helps the blood (血液) to move around inside the body. This is very important. Our blood takes food to all parts of our body. The head also needs blood. Exercise helps us to think better!1. If we get up early and go to bed early, we’ll ______ .A. have enough exerciseB.be healthyC. think betterD. have strong blood2. If a child doesn’t have 10 hours’ sleep, maybe he _____ .A. becomes wiseB. won’t do well in his workC. goes to school in timeD. has enough sleep3. A person needs exercise because _______ .A. it makes him healthyB. he has a lot of homework to doC. he is strong enoughD. he does exercise4. Exercise makes the ______ move quickly and smoothly(流畅).A. BodyB. bloodC. childrenD. head5. Which of the following if Not TRUE?A. Exercise does good to a person’s headB. A student should have 10 hours’ sleepC. It’s good for you to get up early and go to bed early.D. If you have enough blood, you’ll be wise.1-5 BBABD【练习5】Running is becoming popular these days. Many of us run for health. Doctors say many health problems come from these bad habits：eating and drinking too much, smoking and not taking enough exercise. Doctors tell us, “Eat and drink less, don’t smoke, and exercise more.”Running is a good form of exercise because it helps build a strong heart. It also helps most people lose weight. One 68-year-old woman runs three times a week. “I love to eat,” she says. She runs to lose weight.Running is good for health in other ways, too. Many runners say running keeps colds and other small health problems away. “Running is my doctor,” says one man.Running can also help people to relax. So today men and women of all ages enjoy running.1. Many people enjoy running because they want to___________.A. eat muchB. keep healthyC. run fastD. waste time2. Doctors tell us _____________.A. not to smokeB. not to exerciseC. to drink muchD. to eat much3. The underlined word means “_______” in Chinese.A. 疾病B. 体重C. 速度D. 健康4. The third paragraph shows_____________.A. running helps people to relaxB. people who like running have many health problemsC. running helps build a strong heartD. people who like running have fewer health problems5. The writer mainly tells us ___________.A. how to runB. how to lose weightC. running is a good way to keep healthyD. running is better than doctors1-5 BABDC【练习6】Mary Jo Ray turned 113 in May, 2008. She was the twelfth oldest person in the world. Ray was one of the few people who lived to more than (多于) 110 years old. We often call them. “She often drinks milk. She hardly gets angry with others and is always happy. So she is in good health. I think her reason for long life is drinking milk every day and trying to be happy,” said her granddaughter (孙女).Her doctor, Dr. Perls, said another reason for Ray’s long life is her genes (基因). She got them from her parents. He said, “These genes can keep you in good health and let you live longer. People can usually live to about 80 years old. Those with the right genes can live to more than 100 years. They also pass those genes to their children. So if a person’s parents live long, he or she will probably live long, too.” Dr. Perls also said, “You may not have those genes. But if you don’t smoke, don’t drink too much, and do exercise or do other things to relax, you still can live long.”1. Mary Jo Ray was the ______ oldest person in the world in 2008.A.11thB.12thC.13thD.14th2. The underlined word “centenarian” means “_______” in Chinese.A. 健康的人B. 聪明的人C. 杰出的人D.百岁的人3. From the passage, we can learn that Mary Jo Ray ___________.A. hardly drinks milkB.is never happyC. has the genes for long lifeD. often gets angry with others4. Mary Jo Ray’s father probably lived a(n) _______ life.A. LongB. hardC. shortD. easy5. The passage is mainly about _______.A. the family of Mary Jo RayB. how people can live betterC. why Mary Jo Ray lives longD. Mary Jo Ray’s doctor1-5 BDCAC【练习7】Coffee has played an important role in people’s lives for thousands of years, and today coffee is grown and enjoyed worldwide; it is still one of the favorite drinks in the world. Many people in the world begin their busy day by drinking a cup of coffee or several cups of coffee. They have always said that a cup of coffee in the morning helps them begin their day in the right way.Do you know what in the coffee makes our bodies and brains (头脑) active? It is caffeine (咖啡因). Caffeine may increase a person’s mental and physical abilities (精力和体力). For example, two cups of coffee will make you breathe (呼吸) faster and augment body temperature. All this makes your heart beat faster, and doctors warn that this may be a little dangerous.Caffeine is found in tea, coffee, chocolate and some other foods. A little caffeine is probably not harmful. But too much caffeine can make people nervous and sleepless.1.“A cup of coffee in the morning helps them begin their day in the right way.” What does it mean?A. A cup of coffee helps them do the right job.B. A cup of coffee helps them act in the right way the whole morning.C. A cup of coffee makes their work more interesting.D. A cup of coffee makes them full of spirit for the work the whole day.2. The underlined word “augment” means __________.A. make moreB. drinkC. stopD. make less3. Caffeine is found in __________.A. tea and waterB. chocolate, meat and some other foodsC. coffee and creamD. coffee, tea, chocolate and some other foods4. From the passage, we may know drinking coffee late at night might _________.A. give you a headacheB. make you fall asleepC. keep you awakeD. may be dangerous5. Which of the following is NOT true?A. People have used coffee since thousands of years ago.B. Caffeine does no harm to our body.C. Two cups of coffee will make you breathe faster and increase body temperature.D. Caffeine may increase man’s mental and physical abilities.1-5 DADCB【练习8】“ Early to bed and early to rise make a man healthy , wealthy and wise.” This is an old English saying. It means that when we go to bed early, we can get up early the next morning. Then we will become healthy. We will also become rich and clever.This is true. To keep healthy, we must have enough sleep. Experts (专家) say that adults should get seven to eight hours of sleep a night. Teenagers need nine to ten hours. And school-aged children may need more than ten hours of sleep. Children who do not have enough sleep can’t do their work very well. They won’t be wise and they may not become wealthy！We also need exercise. Walking, running, swimming and playing games are all exercise. Exercise keeps us strong. It also helps the blood to move around the body. This is very important. Our blood takes the nutrition (营养) from food to all parts of our body.The head also needs blood. So exercise that moves the blood to our head helps us think better！1. If we get up early and go to bed early, we’ll .A. become weakB. have more timeC. be healthyD. have more work to do2. Who needs most hours of sleep to keep healthy？A. Adults.B. Teenagers.C. Experts.D. School-aged children.3. A child when he does not have enough sleep.A. can’t study wellB. will be wiseC. will be wealthyD. will be active in class4. A person needs exercise because .A. he is not strong enoughB. it helps make him healthyC. he has a lot of homework to doD. it can bring him much blood5. Which of the following is NOT true？A. Exercise helps the blood to move.B. Exercise is good for a person’s head.C. If we have enough blood, we’ll be wise.D. It’s good for us to get up early and go to bed early.1-5 C D A B C【练习9】Hobbies are very important to a person. Without having any hobby, life won’t be as colorful as it should be.I have a number of hobbies , such as collecting stamps, playing musical instruments (乐器), reading, and doing sport activities. When I am free,1 will spend time on my hobbies. When I am in a blue mood (情绪低落), I will also do my hobbies to cheer myself up.Hobbies can help us improve our moods. Many hobbies require you to put your heart in them. For example , when you play a musical instrument , you have to practice over and over in order to perform (表演) good music. After a period (一段时期) if you still enjoy it ,gradually (逐渐地) it will become a hobby of yours. But remember ,a hobby is like gold (金子) under the ground; no hobby will come to your unless (除非) you dig it out yourself. If you can treat study as one of your hobbies, learning will be more enjoyable. I hope all of you can find your own hobbies and also have fun from them.1. What makes our life colorful？A. Playing musical instruments.B. Collecting stamps.C. The blue mood.D. The hobbies.2. Hobbies sometimes can make a personA. in a blue moodB. find gold under the groundC. cheer himself/herself upD. perform good3. If we want to have a hobby, we mustA. practice over and over.B. put our heart in it.C. spend a lot of time on it.D. all the above.4. How can we make our study enjoyable？A. Practice over and over.B. Improve our moods.C. Treat our study as a hobby.D. We shouldn’t have hobbies5. Which of these is WRONG?A. Hobbies are important for a person.B. Playing musical instruments is a Kind of hobby.C. If we often do something and don’t enjoy doing it, it will be our hobbies someday.D. A hobby can be gold if we dig it.1-5 D C B C C【练习10】You may hear about earthquakes, but do you know, what to do before, during and after an earthquake? Here is some advice for you:Before an earthquake. It’s necessary to prepare yourself and your family. All family members should know how to turn off gas, water and electricity and Know useful telephone numbers (doctor, hospital, police ,119, etc.). Never put heavy things over beds.During an earthquake. It’s important for each of you to stay calm( 冷静) . If you are indoors, quickly move to a safe place in the room such as under a strong desk or a strong table, the purpose is to protect yourself from falling objects. Stay away from windows, large mirrors, heavy furniture and so on. If you are cooking, turn off the gas.If you are outdoors, move to an open area like a playground. Move away from buildings, bridges and trees. If you are driving, stop the car as soon as possible, staying away from bridges and tall buildings Stay in your car.After an earthquake once the shaking has stopped, do not run out of the building at once. It’s better to wait and leave when it is safe.Check around you and help the people who are in trouble. If your building is badly broken you should leave it. If you smell or hear a gas, get everyone outside and open windows and doors. If you can do it safely, turn off the gas. Report it to the gas company.1. Which of the following is mentioned in the second paragraph？A. People should know how to turn on gas.B. People should know how to save water.C. People shouldn’t put heavy boxes over beds.D. People shouldn’t forget the phone numbers of others.2. When an earthquake happens, can help you deal with it.A. standing stillB. staying calmC. looking outsideD. moving indoors3. During an earthquake, if you are driving in an open area, you should .A. speed up your car B stop your car and stay inC. slow down your carD. stop your car and run out4. When the earth stops shaking, you should .A. check around you firstB. run out of the building at onceC. break the windows and doorsD. write a report to your company5. You can learn after reading the passage.A. what an earthquake is likeB. what to do to avoid earthquakeC. how an earthquake happensD. how to protect yourself in an earthquake1-5 D B B A D【练习11】Do you know the story about Vince? It was a true story. Vince was an English boy and he was eight years old. He didn’t like soap or water. Three or four times a day his mother said to him, “Vince, your hands are very dirty again.” Go and wash them.” But Vince never washed them well. He only put his hands in the water for a few seconds and then took them out again.Vince’s uncle and aunt lived in another city. One day they came to stay with Vince’s parents, and they brought their small son, Toby, with them. Toby was seven years old and he didn’t like soap or water, either. The boys sat with their parents for a few minutes and then they went outside. When they were playing, Vince looked at Toby’s hands and then went back to Toby’s parents and said proudly (骄傲地), “Toby’s hands are dirtier than mine, ” “Of course they are,” Toby said angrily. “You are one year older than I am.”1. Vince’s mother asked him to______ three or four times a day.A. wash his handsB.do his homeworkC. clean his bedroomD. wash his teeth2. When Vince saw Toby’s hands, he felt ________.A. SorryB. proudC. sadD. terrible3. Vince’s hands were a little______ than Toby’s.A. DirtierB. cleanerC. biggerD. smaller4. From the story we know that_______ .A. Vince liked soap and water, but Toby didn’t.B. Toby liked soap and water, but Vince didn’t.C. Vince and Toby liked soap and water.D. Vince and Toby didn’t like soap or water.5. How many people are there in the story?A. Four.B. FiveC. Six.D. Seven.1-5 ABBD【练习12】One day, there was a blind man called John sitting on the bench with a hat by his feet and a sign that read, “I am blind. Please help me.”A creative publicist (广告员) named Tom was walking by the blind man and stopped to see that the man only had a few coins in his hat. He put a few of his own coins in the hat.Without asking for permission (允许), he took the sign, turned it around and wrote a new message. Then he put the sign by the feet of the blind man and left.Later that afternoon the publicist returned to the blind man and noticed that his hat was almost full of bills (钞票) and coins. The blind man recognized (识别) his footsteps and asked if it was he who had changed his sign. He also wanted to know what the man wrote on it.The publicist said, “I just wrote the message a little differently.” He smiled and went on his way.The new sign read, “Spring has come, but I can’t see anything.”1. What’s the blind man’s name?A. Tom.B. John.C. Tony.D. Sorry, I don’t know.2. Who wrote a new message?A. The blind man.B. The teacher.C. The publicist.D. The farmer.3. How did the blind man recognize the publicist?A. By his sign.B. By his footsteps.C. By his voice.D. By his coins.4. When did the story happen?A. In spring.B. In summer.C. In autumn.D. In winter.5. What can we learn from the passage?A. Publicists are always curious (好奇) about everything.B. We can get more money by changing a sign.C. The blind man is not clever, so he has little money.D. The power of language is great.1-5CBCBA。

第五单元简易方程重难点强化小专题(八) 解方程实际问题与方程一、仓库里有货物35吨，要用一辆卡车把它全部运走，卡车每次运5吨，上午已运3次，下午要几次才能运完？二、有一条8.4米长的红绳做了4个同样的“中国结”，这时还剩0.4米。

每个中国结需要多长的红绳？三、奇思和妙想家相距1120米，奇思要把文具还给妙想，两人相约同时从家里出发，奇思每分走76米，妙想每分走84米，几分钟两人相遇？四、海龟的寿命是140年，海龟的寿命比河马的3倍还多20年，河马的寿命约是多少年？五、小艳的画片数是小美的1.5倍，小艳给小美5张，小艳和小美的画片就一样多。

小艳有多少张画片？六、两辆汽车从相距228千米的两地同时相向而行，行驶2.5小时后，还相距28千米，已知甲车每小时行38千米，乙车每小时行多少千米？第五单元简易方程重难点强化小专题(八) 解方程实际问题与方程一、仓库里有货物35吨，要用一辆卡车把它全部运走，卡车每次运5吨，上午已运3次，下午要几次才能运完？解：设下午还要x次才能运完。

3×5＋5x＝3515－15＋5x＝35－15x＝4答：下午还需要运4次。

二、有一条8.4米长的红绳做了4个同样的“中国结”，这时还剩0.4米。

每个中国结需要多长的红绳？解：设每个中国结需要x米红绳。

4x＋0.4＝8.44x＋0.4－0.4＝8.4－0.44x＝8x＝2答：每个中国结需要2米长的红绳。

三、奇思和妙想家相距1120米，奇思要把文具还给妙想，两人相约同时从家里出发，奇思每分走76米，妙想每分走84米，几分钟两人相遇？解：设经过x分钟两人相遇。

76x＋84x＝1120160x÷160＝1120÷160x＝7答：经过7分钟两人相遇。

四、海龟的寿命是140年，海龟的寿命比河马的3倍还多20年，河马的寿命约是多少年？解：设河马的寿命约是x年。

3x＋20＝1403x＋20－20＝140－203x＝120x＝40答：河马的寿命约是40年。

2020-2021学年小升初专题测评必刷卷（8）图形的拼组与图形变换测试时间：90分钟满分：100分+30分题号一二三四五B卷总分得分A 卷基础训练（100 分）一、选择题（每题2分，共20分）1．（2020·浙江小升初真题）一个长、宽都是4厘米，高12厘米的长方体截成三个一样大小的正方体，表面积增加了（）平方厘米。

A．16 B．32 C．48 D．642．（2020·全国小升初模拟）最少（）个小正方体可以拼出一个大正方体。

A．4 B．6 C．83．（2020·江苏苏州市·小升初真题）一个长方体刚好切成3个相同的正方体，表面积增加了36dm2，原来长方体的体积是（）dm3。

A．108 B．81 C．432 D．6484．（2020·江苏无锡市·小升初真题）把两个棱长为3厘米的正方体木块和一个长12厘米，宽6厘米，高6厘米的长方体木块粘贴在一起（如图），那么粘贴后的表面积比原来三个木块表面积之和减少（）。

A．54平方厘米B．36平方厘米C．27平方厘米D．18平方厘米5．（2021·江苏无锡市·小升初模拟）一个长方体盒子，从里面量，长6分米，宽5分米，高4分米。

如果把棱长2分米的积木装进盒子，并使积木不外露，最多可以装（）块。

A．6 B．10 C．12 D．156．（2020·江苏小升初模拟）把一个圆平均分成16份，然后剪拼成一个近似的长方形，转化后的长方形与圆相比，（）。

A．周长和面积都没变B．周长和面积都变了C．周长没变，面积变了D．周长变了，面积不变7．（2020·北京小升初模拟）把一张平行四边形卡片剪一刀分成两个图形，下面几种情况中不可能出现的是（）。

A．两个三角形B．两个平行四边形C．两个梯形D．一个平行四边形与一个梯形来吗？（）A．B．C．9．（2020·全国小升初模拟）如图甲、乙两个图形都是由大小相等的小正方体组成的，他们的表面积相比，（）。

沪科版八年级物理第八章 压强专题练习考试时间：90分钟；命题人：物理教研组考生注意：1、本卷分第I 卷（选择题）和第Ⅱ卷（非选择题）两部分，满分100分，考试时间90分钟2、答卷前，考生务必用0.5毫米黑色签字笔将自己的姓名、班级填写在试卷规定位置上3、答案必须写在试卷各个题目指定区域内相应的位置，如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带，不按以上要求作答的答案无效。

第I 卷（选择题 30分）一、单选题（10小题，每小题3分，共计30分）1、如图所示，甲、乙为两个体积相同的实心柱体，密度分别为ρ甲、ρ乙，它们对水平地面的压强相等；现沿水平方向将甲、乙截去相同的体积，甲、乙对地面压强变化量为p ∆甲、p ∆乙；则（ ）A ． ρρ>乙甲， ΔΔp p =乙甲B ． ρρ>乙甲， ΔΔp p >甲乙C ． ρρ<乙甲， ΔΔp p =乙甲D ． ρρ<乙甲， ΔΔp p <乙甲2、下列生活现象不属于利用大气压的实例是（ ） A ．钢笔把墨水吸进钢笔的墨囊中 B ．真空包装的食品被压得紧紧的 C ．用注射器能把药液注入肌肉里D ．用吸尘器能吸取地板上的灰尘3、如图是冰壶比赛时的情景，运动员穿的两只鞋的鞋底材质并不相同：蹬冰脚的鞋底为橡胶制成，滑行脚的鞋底为塑料制成（ ）A．蹬冰脚的鞋底能减小压力B．蹬冰脚的鞋底能减小摩擦C．滑行脚的鞋底能减小摩擦D．滑行脚的鞋底能增大压强4、首先用实验测定大气压强值的意大利物理学家是（）A．托里拆利B．阿基米德C．牛顿D．欧姆5、下列数据中，你认为最符合生活实际的是（）A．教室中空气的质量大约是300gB．一名初中生的密度大约是1g/cm3C．真空中光传播的速度大约是3×108km/sD．一名初中生双脚站立时对地面的压强大约是32Pa6、将塑料杯装满水，用硬纸片盖紧杯口，手压紧硬纸片，然后将塑料杯上下倒转，纸片受到大气对硬纸片的压力，如图所示，若将塑料杯倾斜，纸片受到大气压力正确的是（）A．B．C ．D ．7、下列生活中的事例，没有利用连通器原理的是（ ） A ．水位计B ．注射器C ．船闸D ．茶壶8、甲、乙是由同种材料制成的规格相同的实心长方体，现将乙平放在水平面上，甲整放在乙的上表面中央，若长方体的长、宽、高三者中，长度为a 、高度为c ，a 与c 之比为3∶1，如图所示。

20242025学年浙教版八年级上册科学1.3浮力培优训练一、选择题1． (杭州市文理中学2023学年第一学期八年级1月作业回顾)如图所示，下列与浮力有关的事例说法正确的是（）A．图甲中，鸡蛋悬浮在浓盐水中，向杯中加水，鸡蛋所受浮力不变B．图乙中，舰载机起飞后，航母受到的浮力不变C．图丙中，在空中向左匀速飘动的热气球，它所受到浮力方向是向左D．图丁中，同一支密度计静止在不同液体中，液体A的密度小于液体B的密度2． (乐清市八校联盟八年级 (上)期末模拟考)某同学制作了如图所示的潜艇模型，下列说法中错误的是（）A．潜艇模型是通过改变潜艇的重力实现沉浮的B．向内推注射器活塞，水会被压入试管中，可实现潜艇下沉C．向外拉注射器活塞，试管内水量适当时，可实现潜艇悬浮D．潜艇模型的试管上绕些铁丝，可保持试管在水中稳定3． (2024年浙江省舟山市定海区中考三模科学试题)如图是舟山沈家门海底隧道的施工现场，起重船将圆柱形物体放入水中至全部浸没的过程中，起重船所受浮力大小的变化是（）A．B．C．D．4． (杭州市文理中学2023学年第一学期八年级1月作业回顾)如图所示，水槽中有三个等质量的实心物体处于静止状态，甲、乙为长方体，丙为球体。

下列有关说法正确的是（）A．丙物体排开的水的体积最多B．乙物体受到的浮力最小C．甲物体的密度大于乙物体的密度D．无法判断三个物体之间的密度大小关系5． (20232024学年浙江省台州市玉环市八年级（上）期末科学试卷)如图所示，不同的水果在水中静止时所处的位置，下列说法正确的是（）A．青枣处于悬浮状态B．苹果受到的浮力比重力大C．葡萄受到的浮力等于它排开水的重力D．葡萄在下沉过程中所受水的压强不变6． (20232024学年浙江省宁波市宁海县八年级（上）期末科学试卷)我国研制的水下滑翔机“海燕﹣X”，将世界深海下潜最大深度“刷新”到了10619米。

如图所示是水下滑翔机的模型，机身上搭载的油囊可在油泵的控制下进行收缩或膨胀。

重难点强化小专题(八)不规则物体的体积一、我会填。

1．把一块石头丢进装满水的杯子里水溢出100 mL，则这块石头的体积是(100)cm3。

2．一瓶装有250 mL饮料的瓶子，它的(容积)是250 mL。

3．一个量杯原来装有150 mL水，后来放入一枚鸡蛋后，水面上升到200 mL的刻度线，这枚鸡蛋的体积是(50)cm3。

二、我会选。

1．一个底面积是3平方分米的长方体铁盒，先注入2分米高的水，又投入300 cm3的西红柿，这时长方体铁盒所装物体的体积是(B)。

A．306 dm3B．6300 cm3C．1800 cm32．一块40 cm3的石块完全浸入一个长5 cm、宽4 cm的长方体容器中，水面会上升(A)。

A．2 cm B．5 cm C．4 cm3．一个装有假山的底面积为30平方分米的玻璃鱼缸装满了水，取出假山后，水面下降了3厘米，假山的体积是(B)立方分米。

A．90 B．9 C．33三、我会解决问题。

1．一个长80 cm，宽40 cm，高3 dm的长方体玻璃缸中水深20 cm，放入10颗鹅卵石后水面上升了2 cm。

平均每颗鹅卵石的体积是多少立方厘米？80×40×2＝6400(立方厘米)6400÷10＝640(立方厘米)答：平均每颗鹅卵石的体积是640立方厘米。

2．一个正方体容器，从里面量棱长为4分米，向容器中倒入10 L水，再把一个苹果放入水中，这时水深8 cm。

这个苹果的体积是多少立方分米？8 cm＝0.8 dm4×4×0.8＝12.8(dm3)12．8－10＝0.8(dm3)答：这个苹果的体积是0.8立方分米。

3．小豆豆家有一个长50厘米、宽20厘米的玻璃器皿，里面水深为30厘米。

一天，小豆豆不小心将一块棱长为8厘米的正方体铁盒掉入缸中，缸中的水面将升到多少厘米？83＝512(cm3)512÷(50×20)＝5.12(cm)30＋5.12＝35.12(cm)答：缸中的水面将升到35.12厘米。

上海高考专题训练-上海重点高中专项训练-完型填空强化篇训练高中完型填空强化篇训练（八）passage1The earthquake of26th December2004resulted in one of the worst natural disasters in living memory．It was a__1___underwater quake and occurred in the Indian Ocean．It__2__coastlines，communities and brought death to many people．Why do earthquakes happen?The surface of the earth has not always looked as it does today；it is moving__3__(although very slowly)and has done so for billions of years．This is one__4__of earthquakes，when one section of the earth(tectonic plate)__5__ another．Scientists can predict where but not when_this might happen and the area between plates is called a fault line．On one fault line in Kobe，Japan in1923over 200,000people were killed．__6__，earthquakes do not always happen on fault lines，which is why they are so dangerous and__7__．Where do volcanoes happen?Volcanoes happen where the earth's__8__is thin：lava，dust and gases__9__ from beneath the earth．They can rise into a huge cone shape like a mountain and erupt，__10__they can be so violent that they just explode directly from the earth with no warning．There are1511'__11__'volcanoes in the world．This means that they may__12__be dangerous．In1985the Colombian volcano Nevado del Ruiz erupted．The lava melted a glacier and sent tones of mud down the town below．Twenty thousand people died．Natural disasters like volcanic eruptions are often unpredictable．We regularly do not know when they might pen，or__13__ where they will happen．In the future，scientists may be able to watch and predict__14__before they happen．This could__15__many lives．1．A．massive B．significant C．great D．grand 2．A．changed B．converted C．destroyed D．transformed 3．A．frequently B．continuously C．regularly D．periodically 4．A．source B．reason C．movement D．cause 5．A．collides with B．confronts with C．meets with D．faces with 6．A．Generally B．However C．Similarly D．Anyway 7．A．unpredictable B．unaccountable C．inevitable D．irresistible 8．A．surface B．appearance C．crust D．cover 9．A．flowed out B．burst out C．1eaked out D．trickled out 10．A．or B．and C．nor D．but 11．A．living B．active C．alive D．live 12．A．relatively B．hardly C．still D．gradually 13．A．else B．even C．though D．whether 14．A．accidents B．incidents C．occasions D．events 15．A．rescue B．save C．preserve D．shelter Keys:1-5ACBDA6-10BACBA11-15BCBDBpassage2The Victorians had become addicted to speed and they wanted to go ever faster. Time was money and efficiency became__1__important.Although divisions of labour had been__2__by Adam Smith and illustrated by a pin factory in The Wealth of Nations in1776,it could now become fully realised.This specialization of labour was in__3__contrast to the rural means of production,in which the family was the means of production,consumption and socialization.__4__greater speed came a greater need for industries and businesses to make more and make it quicker. Steam made this__5__and changed working life forever__6__were the days when work was__7__by natural forces:steam engines were servant to neither season nor sunshine.Factories had foremen and life became correspondingly more__8__. The clocking-on machine was__9__in1885and time and motion studies to increase efficiency would be introduced only some twenty years later.__10__it was not all bad news.Agricultural incomes depended on variable harvests and weather.Factories provided__11__and predictable income,but long hours.Working life was becoming increasingly regulated,and the working__12__was reorganised to promote ever-greater efficiency.The old__13__St.Monday-when no work was done-was__14_,work stopped around midday on Saturday and did not resume until Monday morning.A new division between“work”and“leisure”emerged, and this new block of weekend leisure time coincided with the development of spectator sports like cricket and football,and the__15__of music hall entertainment for the new working classes.1．A．increasingly B．surprisingly C．slowly D．obviously 2．A．contributed B．informed C．spread D．conceived 3．A．clear B．marked C．apparent D．firm 4．A．Upon B．Over C．With D．For 5．A．possible B．practical C．worthwhile D．useful 6．A．Passed B．Lost C．Gone D．Missed 7．A．defined B．controlled C．limited D．dictated 8．A．standard B．controlled C．difficult D．dreadful 9．A．designed B．created C．invented D．bought 10．A．For B．But C．ConsequentlyD．Accordingly 11．A．safe B．good C．continuous D．secure 12．A．week B．period C．pattern D．practice 13．A．culture B．behavior C．custom D．habit 14．A．repair B．compensate C．mend D．moderate 15．A．raise B．increase C．trend D．present Keys:1-5ADBCA6-10CDBCB11-15DACCApassage3Reading involves looking at graphic symbols and formulating mentally the sounds and ideas they represent.Concepts of reading have changed__1__over the centuries.During the1950's and1960's especially,increased attention has been devoted to defining and describing the reading process.Although specialists agree that reading__2__a complex organization of higher mental__3__,they disagree about the exact nature of the process.Some experts,who regard language primarily as a code using symbols to represent sounds,__4__reading as simply the decoding of symbols sintos the sounds they stand for.These authorities__5__that meaning,being concerned with thinking,must be taught independently of the decoding process.Others maintain that reading is __6__related to thinking,and that a child who pronounces sounds withou__7__their meaning is not truly reading.The reader,__8__some,is not just a person with a theoretical ability to read but one who__9__reads.Many adults,although they have the ability to read,have never read a book in its __10__.By some expert they would not be__11__as readers.Clearly,the philosophy,objectives,methods and materials of reading will depend on the definition one use.By the most__12__and satisfactory definition,reading is the ability to__13__the sound-symbols code of the language,to interpret meaning for various__14__,at various rates,and at various levels of difficulty,and to do so widely and enthusiastically.__15__reading is the interpretation of ideas through the use of symbols representing sounds and ideas.1．A．substantively B．substantially C．substitutively D．subjectively 2．A．involves B．involves to C．is involved D．involves of 3．A．opinions B．effects C．manners D．functions 4．A．view B．look C．reassure D．agree 5．A．content B．contend C．contempt D．contact 6．A．inexplicably B．inexpressiblyC．inextricably D．inexpediently 7．A．interpreting B．saying C．explaining D．reading 8．A．like B．for example C．according to D．as 9．A．sometimes B．might C．practical D．actually 10．A．entire B．entirety C．entirely D．entity 11．A．classed B．granted C．classified D．graded 12．A．inclusive B．inclinable C．conclusive D．complicated 13．A．break up B．elaborate C．define D．unlock 14．A．purposes B．degrees C．stages D．steps 15．A．By the way B．In shortC．So far D．On the other handKeys:1-5BADAB6-10AACDB11-15CCDABpassage4Kimiyuki Suda should be a perfect customer for Japan's carmakers.He's a young, successful executive at an Internet-services company in Tokyo and has plenty of disposable___1___.He used to own Toyota's Hilux Surf,a sport utility vehicle.But now he uses___2___subways and trains."It's not inconvenient at all,"he says. Besides,"having a car is so20th century."Suda reflects a worrisome___3___in Japan;the automobile is losing its emotional appeal,___4___among the young,who prefer to spend their money on the latest electronic devices.While minicars and luxury foreign brands are still popular,everything in between is___5___.Last year sales fell6.7percent—7.6 percent if you don't count the minicar market.There have been___6___one-year drops in other nations:sales in Germany fell9percent in2007___7___a tax increase.But experts say Japan is___8___in that sales have been decreasing steadily over time.Since1990,yearly new-car sales have fallen from7.8million to 5.4million units in2007.Alarmed by this state of___9___,the Japan Automobile Manufacturers Association___10___a comprehensive study of the market in2006.It found a ___11___wealth gap,demographic(人口结构的)changes and___12___lack of interest in cars led Japanese to hold their___13___longer,replace their cars with smaller ones or give up car ownership altogether.JAMA___14___a further sales decline of1.2percent in2008.Some experts believe that if the trend continues for much longer,further consolidation(结构)in the automotive sector is___15___. 1．A．profit B．payment C．income D．budget 2．A．mostly B．partially C．occasionally D．rarely 3．A．drift B．tide C．current D．trend 4．A．remarkably B．essentially C．specially D．particularly 5．A．surging B．stretching C．slipping D．shaking 6．A．lower B．slighter C．broader D．larger 7．A．liable to B．in terms of C．thanks to D．in view of 8．A．unique B．similar C．mysterious D．strange 9．A．mess B．boom C．growth D．decay 10．A．proceeded B．relieved C．launched D．revised 11．A．quickening B．widening C．strengthening D．lengthening 12．A．average B．massive C．abundant D．general 13．A．labels B．cycles C．vehicles D．devices 14．A．concludes B．predicts C．reckons D．prescribes 15．A．distant B．likely C．temporary D．immediate Keys:1-5CADDC6-10DCADC11-15BDDBBpassage5From childhood to old age,we all use language as a means of broadening our knowledge of ourselves and the world about us.When humans first____1____, they were like newborn children,unable to use this_____2____tool.Yet once language developed,the possibilities for human kind‘s future____3_____and cultural growth increased.Many linguists believe that evolution is_____4____for our ability to produce and use language.They____5_____that our highly evolved brain provides us with an innate language ability not found in lower____6_____.Proponents of this innateness theory say that our____7_____for language is inborn,but that language itself develops gradually,as a function of the growth of the brain during childhood. Therefore there are critical____8_____times for language development.Current____9_____of innateness theory are mixed,however,evidence supporting the existence of some innate abilities is undeniable._____10____,more and more schools are discovering that foreign languages are best taught in the lowergrades.Young children often can learn several languages by being exposed to them,while adults have a much harder time learning another language once the _____11____of their first language have become firmly fixed.Although some aspects of language are undeniably innate,language does not develop automatically ina vacuum.Children who have been____12_____from other human beings do not possess language.This demonstrates that____13_____ with other human beings is necessary for proper language development.Some linguists believe that this is even more basic to human language_____14____than any innate capacities.These theorists view language as imitative,learned behavior.____15_____,children learn language from their parents by imitating them. Parents gradually shape their child's language skills by positively reinforcing precise imitations and negatively reinforcing imprecise ones.1．A．generated B．evolved C．born D．originated 2．A．valuable B．appropriate C．convenient D．favorite 3．A．attainments B．feasibilityC．entertainments D．evolution 4．A．essential B．available C．reliable D．responsible 5．A．confirm B．inform C．claim D．convince 6．A．organizations B．organisms C．humans D．children 7．A．potential B．performance C．preference D．passion 8．A．ideological B．biological C．social D．psychological 9．A．reviews B．referenceC．reaction D．recommendation10．A．In a word B．In a sense C．Indeed D．In other words 11．A．regulations B．formations C．rules D．constitutions 12．A．distinguished B．different C．protected D．isolated 13．A．exposition B．comparison C．contrast D．interaction 14．A．acquisition B．appreciation C．requirement D．alternative 15．A．As a result B．After allC．In other words D．Above all Keys:1-5BAADC6-10BABAC11-15CDDACpassage6A translator must have an excellent,up-to-date knowledge of his source languages.He must fill facility in the handling of his target language,which will be his mother tongue or language of habitual__1__,and a knowledge and understanding of the latest subject-matter in his field of specialization.This is,as it were,his professional__2__.In addition to this,it is__3__that he should have an enquiring mind,wide interests,a good memory and the ability to__4__quickly the basic principles of new developments.He should be willing to work on his own,often at high speeds,but should be humble enough to__5__other people because his own knowledge does not always prove adequate to the task in hand.He should be able to type fairly quickly and __6__and,if he is working mainly for publication,should have more than a nodding __7__with printing techniques and proof-reading.If he is working basically as an information translator,let us say,for an industrial firms,he should have the flexibility of mind to enable him to__8__ rapidly from one source language to another,as well as from one subject-matter to another,since this ability is frequently__9__of him in such work.Bearing in mind the nature of the translator’s work,i.e.the processing of the written word,it is, strictly speaking,__10__that he should be able to speak the languages he is dealing with.If he does speak them,it is an__11__rather than a hindrance(障碍),but this skill is in many ways a luxury that he can do away with.It is,__12__,desirable that he should have an__13__idea about the pronunciation of his source languages,even if this is restricted to knowing how proper names and place names are pronounced. The same__14__to an ability to write his source languages.If he can,well and good; if he cannot,it does not_15__.1．A．application B．use C．utility D．usage 2．A．equipment B．language C．performance D．facility 3．A．wise B．unique C．desirable D．effective 4．A．input B．grasp C．seek D．expand 5．A．learn B．imitate C．conduct D．consult 6．A．steadily B．accurately C．regularly D．reasonably 7．A．familiarity B．acquaintanceC．knowledge D．skill 8．A．change B．transform C．turn D．switch 9．A．lacked B．required C．faced D．confronted 10．A．essential B．unnecessary C．advantageous D．useless 11．A．idea B．advice C．advantage D．accordance 12．A．however B．accordingly C．consequently D．thus 13．A．adjacent B．ambiguous C．artificial D．approximate 14．A．refers B．comes C．applies D．amounts 15．A．matter B．mind C．harm D．workKeys:1-5DACBD6-10BBDBB11-15CADCA。

沪科版八年级物理第八章压强专题训练考试时间：90分钟；命题人：物理教研组考生注意：1、本卷分第I卷（选择题）和第Ⅱ卷（非选择题）两部分，满分100分，考试时间90分钟2、答卷前，考生务必用0.5毫米黑色签字笔将自己的姓名、班级填写在试卷规定位置上3、答案必须写在试卷各个题目指定区域内相应的位置，如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带，不按以上要求作答的答案无效。

第I卷（选择题 30分）一、单选题（10小题，每小题3分，共计30分）1、容器中间用隔板分成左右两个部分，隔板下部有一圆孔用面积为1cm2的薄橡皮膜封闭。

在容器左右两侧分别倒入水和酒精，橡皮膜中心到水面的距离为0.1m，如图所示，橡皮膜相平。

下列结论正确的是（）A．酒精对容器底部的压强等于水对容器底部的压强B．酒精对橡皮膜的压力为10NC．容器右侧中酒精的深度为12.5cmD．容器右侧液面比左侧水面高2.5cm2、将塑料杯装满水，用硬纸片盖紧杯口，手压紧硬纸片，然后将塑料杯上下倒转，纸片受到大气对硬纸片的压力，如图所示，若将塑料杯倾斜，纸片受到大气压力正确的是（）A．B．C．D．3、如图所示，公交车上安全锤的一端做得很尖锐是为了（）A．减小压力B．增大压力C．减小压强D．增大压强4、图所示的四个实例中，目的是为了减小压强的是（）A．饮料管的一端剪成斜口B．图钉帽的面积做得较大C．切蛋器装有很细的钢丝D．注射器针头做得很尖5、如图所示，两个圆柱形容器A、B，盛有体积相同的同种液体且放置在水平桌面上。

若两容器底部受到的液体压力分别为F A、F B，受到的液体压强分别为p A、p B，则它们的关系是（）A．F A=F B、p A＞p B B．F A=F B、p A＜p BC．F A＞F B、p A=p B D．F A＜F B、p A=p B6、下列说法中正确的是（）A．人潜入较深的水中时，必须穿潜水服，因为液体压强随深度增加而增大B．铲车宽大的轮子可以增大受力面积，增大对地面的压强C．用吸管吸饮料时，是利用了嘴对饮料的作用力将饮料吸入口中D．飞机升力的产生是由于机翼上方的空气流速小于下方的空气流速，形成向上压强差7、如图所示的实例中，利用了“流体压强与流速关系”工作的是（）A．覆杯实验B．飞机机翼上产生的升力C．用注射器吸取药液D．船闸8、如图所示，在水平地面上有甲、乙两个实心正方体，它们对地面的压强p甲＞p乙。

六年级数学第二学期第八章长方体的再认识专题测试考试时间：90分钟；命题人：数学教研组考生注意：1、本卷分第I卷（选择题）和第Ⅱ卷（非选择题）两部分，满分100分，考试时间90分钟2、答卷前，考生务必用0.5毫米黑色签字笔将自己的姓名、班级填写在试卷规定位置上3、答案必须写在试卷各个题目指定区域内相应的位置，如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带，不按以上要求作答的答案无效。

第I卷（选择题 30分）一、单选题（10小题，每小题3分，共计30分）1、一个圆锥的底面直径是圆柱底面直径的3倍，如果它们的高相等，那么圆锥体积是圆柱体积的（）A．3倍B．13C．9倍D．192、若一个棱柱有10个顶点，则下列说法正确的是（）A．这个棱柱有4个侧面B．这个棱柱是一个十棱柱C．这个棱柱的底面是十边形D．这个棱柱有5条侧棱3、下列几何体中，每个面都是由同一种图形组成的是（）A．圆柱B．圆锥C．三棱柱D．正方体4、下列四个几何体中，主视图是三角形的是（）A．B．C．D．5、防控疫情必须勤洗手、戴口罩，讲究个人卫生．如图是一个正方体展开图，现将其围成一个正方体后，则与“手”相对的是（）A．勤B．口C．戴D．罩6、下图是由5个大小相同的正方体组成的立体图形，其俯视图．．．是（）A．B．C．D．7、如图所示的几何体的左视图是（）A．B．C．D．8、如图为某几何体的三视图，则该几何体是（）A．圆锥B．圆柱C．三棱柱D．四棱柱9、两个长方体如图放置，则该立体图形的左视图是（）A．B．C．D．10、下列四个正方体的展开图中，能折叠成如图所示的正方体的是（）A．B．C ．D ．第Ⅱ卷（非选择题 70分）二、填空题（5小题，每小题4分，共计20分）1、已知一个直角三角形的两直角边分别是3和4，将这个直角三角形绕它的直角边所在直线旋转一周，可以得到圆锥，则圆锥的体积是_______．（213π圆锥V r h ，结果保留π） 2、铅笔在纸上划过会留下痕迹，这种现象说明点动成线；一枚硬币在光滑的桌面上快速旋转，看上去像形成了一个球，这体现的数学知识是______．3、如图，一个正方体截去一个角后，剩下的几何体面的个数和棱的条数分别为_____．4、小强用5个大小一样的正方形制成如图所示的拼接图形（阴影部分），若在图中只添加一个正方形，使新拼接成的图形经过折叠后能成为一个封闭的正方体盒子，这样的拼接方式有_____种．5、如图，与棱EH 平行的面是_______．三、解答题（5小题，每小题10分，共计50分）1、如图所示：（1）与面MNQP垂直的面有________________个．（2）与面EFGH平行的面有________________个．（3）与面EFGH垂直的线段有________________条．（4）与线段EF平行的面有________________个．2、如图，是由五个相同的小正方体搭成的几何体，分别画出从正面、左面、上面看到的形状图．3、在长方体ABCD EFGH中，已知从点F出发的三条棱EF、BF、FG的长度比为3:4:3，该长方体的棱长总和为80厘米，求：（1）与平面CGHD垂直的棱的总长；（2）与平面ADHE平行的棱的总长．4、如图所示，将一个横截面是正方形（面BCGF）的长方体木料，沿平面AEGC（长方形）分割成大小相同的两块，表面积增加了218cm，问原来这30cm，已知EG长5cm，分割后每块木料的体积是3块长方体木料的表面积是多少？5、如图所示，几何体是由9个小立方块搭成的几何体，请分别从正面、左面和上面看，试将你所看到的平面图形画出来．-参考答案-一、单选题1、A【分析】设一个圆锥的底面直径为6a，则圆柱底面直径为2a，高为h，根据体积公式分别求出圆锥和圆柱的体积，故可比较求解．【详解】解：设一个圆锥的底面直径为6a，则圆柱底面直径为2a，高为h，∴圆锥的体积为13Sh=22 16332aaππ⎛⎫⨯⨯=⎪⎝⎭圆柱的体积为S’h=2222aa ππ⎛⎫⨯=⎪⎝⎭∴圆锥体积是圆柱体积的3倍故选：A．【点睛】此题主要考查等底等高的圆锥与圆柱体积之间关系的灵活运用，关键是明确：等底等高的圆锥的体积是圆柱体积的13．2、D【分析】根据棱柱的特点即可求解．【详解】解：一个棱柱有10个顶点，则它是五棱柱，五棱柱有5个侧面，有5条侧棱，底面是五边形．故选D．【点睛】本题考查了n棱柱的特征，即棱数与侧棱、与侧面、与底面的边数之间的关系．3、D【分析】分别找出每个图形的每个面是由什么图形组成的即可．【详解】解：A、圆柱是由长方形和圆组成的，故此选项不符合题意；B、圆锥是由扇形和圆组成，故此选项不符合题意；C、三棱柱是由三角形和长方形组成，故此选项不符合题意；D、正方体是由正方形组成，故此选项符合题意；故选：D．【点睛】此题主要考查了认识立体图形，关键是掌握各立体图形的形状．4、C【分析】直接根据三视图中主视图的定义即可判断．【详解】根据几何体三视图中主视图的定义；正方体的主视图是矩形，不符合题意；圆柱体的主视图是矩形，不符合题意；圆锥的主视图是三角形，符合题意；B、球的主视图是圆，不符合题意；故选：C．【点睛】本题考查了几何体的三视图的主视图，解题的关键是：掌握三视图中主视图的定义，是由正面往后看．5、D【分析】正方体的表面展开图，相对的面之间一定相隔一个正方形，根据这一特点作答．【详解】解：勤的对面是戴；洗的对面是口；手的对面是罩；故选：D．【点睛】本题考查正方体相对两面上的字，掌握正方体的表面展开图的特征是正确判断的前提．6、A【分析】俯视图是从上往下看到的图形，注意能看到的棱都要体现出来，根据定义可得答案．【详解】解：从上往下看上层看到一个正方形，下层四个个正方形，所以看到的四个正方形，故选A．【点睛】本题考查的是简单组合体的三视图，掌握三视图的含义是解题的关键．7、A【分析】找到从几何体的左面看所得到的图形即可作答，注意所有的看到的棱都应表现在左视图中．【详解】解：从几何体的左面看，是一行两个矩形．故选：A．【点睛】此题主要考查三视图的判断，解题的关键是熟知三视图的定义．8、C【分析】根据三视图判断该几何体即可．【详解】解：根据该几何体的主视图与左视图均是矩形，主视图中还有一条棱，俯视图是三角形可以判断该几何体为三棱柱．故选：C．【点睛】本题考查三视图，解题的关键是理解三视图的定义，属于中考常考题型．9、B【分析】细心观察图中几何体中正方体摆放的位置，根据左视图是从左面看到的图形判定则可．【详解】从左边看去，由两个长方形组合而成，如图所示：．故选：B．【点睛】本题考查了由三视图判断几何体和简单组合体的三视图，关键是掌握几何体的三视图及空间想象能力．10、B【分析】由正方体的信息可得：面,A 面,B 面C 为相邻面，从相对面与相邻面入手，逐一分析各选项，从而可得答案．【详解】解：由题意可得：正方体中，面,A 面,B 面C 为相邻面．由A 选项的展开图可得面,A 面C 为相对面，故选项A 不符合题意；由B 选项的展开图可得面,A 面,B 面C 为相邻面，故选项B 符合题意；由C 选项的展开图可得面,B 面C 为相对面，故选项C 不符合题意；由D 选项的展开图可得面,A 面B 为相对面，故选项D 不符合题意；故选：.B【点睛】本题考查的是正方体的表面展开图，掌握正方体的表面展开图的特点是解题的关键．二、填空题1、12π或16π或12π【分析】分两种情况：①以直角边为3所在直线旋转一周得到一个圆锥，底面半径是4，高是3，然后利用圆锥的体积公式213π圆锥V r h =，计算即可； ②以直角边为4所在直线旋转一周得到一个圆锥，底面半径是3，高是4，然后利用圆锥的体积公式213π圆锥V r h =，计算即可． 【详解】解：一个直角三角形的两直角边分别是3和4，①以直角边为3所在直线旋转一周得到一个圆锥，底面半径是4，高是3，所以213π圆锥V r h =＝2π431613π⋅⋅=， ②以直角边为4所在直线旋转一周得到一个圆锥，底面半径是3，高是4， 所以213π圆锥V r h =＝2π341213π⋅⋅=， 故答案为：12π或16π．【点睛】此题考查了点、线、面、体中的面动成体，解题关键是：分两种情况①以直角边为3所在直线旋转一周得到一个圆锥，②以直角边为4所在直线旋转一周得到一个圆锥，2、面动成体【分析】根据点、线、面、体的关系解答即可．【详解】解：铅笔在纸上划过会留下痕迹，这种现象说明点动成线；一枚硬币在光滑的桌面上快速旋转，看上去像形成了一个球，这体现的数学知识是面动成体．故答案为：面动成体．【点睛】本题考查了点、线、面、体的关系．解题的关键是明确点动成线，线动成面，面动成体． 3、7，12【分析】正方体切一个顶点多一个面，少三条棱，又多三条棱，依此即可求解．【详解】解：如图，一个正方体截去一个角后，剩下的几何体面的个数是6+1＝7，棱的条数是12﹣3+3＝12 故答案为：7，12此题考查了截一个几何体，解决本题的关键是找到在原来几何体的基础上增加的面和棱数．4、3【分析】结合正方体的平面展开图的特征，只要折叠后能围成正方体即可．【详解】解：根据正方体的表面展开图可得共有3种，如图：【点睛】此题主要考查了正方体的平面展开图，应灵活掌握，不能死记硬背．5、面BCGF，面ABCD【分析】根据长方体中棱与面的位置关系直接作答即可．【详解】由图可知：与棱EH平行的面是面BCGF，面ABCD；故答案为面BCGF，面ABCD．【点睛】本题主要考查长方体中棱与平面的位置关系，正确理解概念是解题的关键．1、（1）5；（2）2；（3）6；（4）4【分析】根据面与面的位置关系和面与线段的位置关系进行判断．【详解】如图所示：（1）与面MNQP垂直的面有：面MPDA、面NQGH、面EFCB、面MNHA、面PQGD，共计5个；（2）与面EFGH平行的面有：面MNQP、面ABCD，共计2个；（3）与面EFGH垂直的线段有：HN、QG、BE、CF、AM、DP，共计6条；（4）与线段EF平行的面有：面MNQP、面ABCD、面NQGH、面AMPD，共计6个．【点睛】考查了面与面的位置关系和面与线段的位置关系，解题关键是理解面与面的平行、面与面垂直、面与线段的平行和面与线段垂直的概念．2、见解析【分析】根据三视图的定义及其分布情况作图可得．【详解】从正面看:从左面看:从上面看:【点睛】本题主要考查作图-三视图，解题的关键是熟练掌握三视图的定义．3、（1）24厘米；（2）28厘米【分析】（1）先根据题意找到与平面CGHD垂直的棱，然后进行求解即可；（2）先找到与平面ADHE平行的棱，然后求解即可．【详解】解：由题意得：80420÷=EF长：332020634310⨯=⨯=++（厘米）BF长：442020834310⨯=⨯=++（厘米）FG长：332020634310⨯=⨯=++（厘米）．（1）与平面CGHD 垂直的棱是：棱EH 、棱FG 、棱BC 、棱AD ，其长度和是：666624+++=（厘米）．（2）与平面ADHE 平行的棱是棱BC 、棱CG 、棱FG 、棱BF ，其长度和为()86228+⨯=（厘米）．【点睛】本题主要考查长方体中棱、面之间的位置关系，关键是先找到棱，然后直接进行求解即可． 4、366cm【分析】根据对角线所在长方形的面积面积求法可得出CG ，即可得到体积；【详解】由题意：长方形AECG 的面积为215cm ，所以1553cm CG =÷=．又因为横截面是正方形，故3cm BC CG ==．而其体积为318236cm ⨯=，所以36334cm AB =÷÷=．原来这块长方体木料的表面积为()2434333266cm ⨯+⨯+⨯⨯=． 答：原来这块长方体木料的表面积是366cm ．【点睛】本题主要考查了长方体的认识，准确计算是解题的关键．5、见解析【分析】从正面看正方体，有3列，每列小正方形数目依次为2，2，1；从左面看正方体，有2列，每列小正方形数目依次为2，2；从上面看正方体，有3列，每列小正方形数目依次为2，2，2．【详解】如图所示，从正面看：从左面看：从上面看：【点睛】本题主要考查从不同的方向观察几何体，解题关键在于画图时，一定要将物体的边缘、棱、顶点都体现出来，不能遗漏．。

沪科版八年级物理第五章质量与密度专题测试考试时间：90分钟；命题人：物理教研组考生注意：1、本卷分第I卷（选择题）和第Ⅱ卷（非选择题）两部分，满分100分，考试时间90分钟2、答卷前，考生务必用0.5毫米黑色签字笔将自己的姓名、班级填写在试卷规定位置上3、答案必须写在试卷各个题目指定区域内相应的位置，如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带，不按以上要求作答的答案无效。

第I卷（选择题 30分）一、单选题（10小题，每小题3分，共计30分）1、我们可以用物理量来描述学习和生活中的一些事物，下列描述合理的是（）A．老师步行的速度是10m s B．一节课的时间是40sC．物理课本的宽度是18.5cm D．铅笔的质量是1kg2、密度知识与生活联系非常紧密，下列关于密度的一些说法中正确的是（）A．物质状态发生变化，密度不变B．乒乓球不慎被挤瘪但无破损，球内气体密度变大C．为减轻质量，比赛用自行车采用强度高、密度大的材料制造D．橡皮在使用过程中受到磨损，密度变小3、①、②、③号三只完全相同的杯子中装有体积不同的水，已知三只杯子中水面高度分别为h1、h2和h3，且h1＞h2＞h3，把质量相等的甲、乙、丙三个实心金属球分别放入①、②、③号杯子中后，水面恰好相平，已知三个金属球都浸没在水中，且均没有水从杯中溢出，对于甲、乙、丙三个实心球的密度大小的判断，下列说法正确的是（）A．甲球的密度最大B．乙球的密度最大C．丙球的密度最大D．三个球的密度一样大4、下列例子中，密度不变的是（）A ．水结成冰B ．铁杵磨成针C ．铜丝被烧红D ．氧气瓶中的氧气被用去一半5、东华大学利用普通纤维膜材料开发出了一种超轻、超弹的“固态纤维气凝胶”，其密度仅为30.12mg/cm ，成功刷新了此前“固态全碳气凝胶”30.16mg/cm 的密度记录，成为世界上最轻的材料。

现有体积为53210cm ⨯的“固态纤维气凝胶”，下列说法正确的是（ ）A ．“固态全碳气凝胶”的密度为331.610g/cm -⨯B ．相同体积的“固态全碳气凝胶”的质量为32gC ．“固态纤维气凝胶”的质量为42.410g ⨯D ．若“固态纤维气凝胶”和“固态全碳气凝胶”的质量相同，则它们的体积之比为3：46、下列估测符合实际的是（ ）A ．成年人的步行速度约为1.2m/sB ．人的心脏正常跳动一次的时间是10sC ．中学生的质量约为500kgD ．一枚硬币的厚度为5mm7、影视剧中，为了防止演员受伤，砸向演员的道具石头一般是用泡沫塑料制成的，将小石块和道具石头分别放在调节好的天平左右盘，横梁静止后的情景如图所示。

六年级数学第二学期第八章长方体的再认识专题攻克考试时间：90分钟；命题人：数学教研组考生注意：1、本卷分第I卷（选择题）和第Ⅱ卷（非选择题）两部分，满分100分，考试时间90分钟2、答卷前，考生务必用0.5毫米黑色签字笔将自己的姓名、班级填写在试卷规定位置上3、答案必须写在试卷各个题目指定区域内相应的位置，如需改动，先划掉原来的答案，然后再写上新的答案；不准使用涂改液、胶带纸、修正带，不按以上要求作答的答案无效。

第I卷（选择题 30分）一、单选题（10小题，每小题3分，共计30分）1、如图是由5个相同的小正方体和1个圆锥组成的立体图形，这个立体图形的主视图是（）A．B．C．D．2、如图，以下三个图形是由立体图形展开得到的，相应的立体图形的顺次是（）A．正方体、圆柱、三棱锥B．正方体、三棱锥、圆柱C．正方体、圆柱、三棱柱D．三棱锥、圆锥、正方体3、某学习小组送给医务工作者的正方体的六个面上都有一个汉字，如图所示的是它的一种展开图，那么在原正方体中，与“美”字所在面相对的面上的汉字是（）A．最B．逆C．行D．人4、将一个等腰三角形绕它的底边旋转一周得到的几何体为（）A．B．C．D．5、如图摆放的几何体的左视图是（）A．B．C．D．6、由6个相同的小正方体搭成的一个几何体如图所示，则它的俯视图为（）A．B．C．D．7、十八世纪瑞士数学家欧拉证明了简单多面体中顶点数()V、面数()F、棱数()E之间存在的一个有趣的关系式：2V F E+-=，被称为欧拉公式．若某个玻璃饰品的外形是简单多面体，它的外表面是由三角形和八边形两种多边形拼接而成，且有24个顶点，每个顶点处都有3条棱，设该多面体外表+的值为（）三角形的个数为x个，八边形的个数为y个，求x yA．12 B．14 C．16 D．188、如图，该几何体的三视图中面积相等的是（）A．主视图与俯视图B．主视图与左视图C．俯视图与左视图D．三个视图都不相等9、如图是一个圆台状灯罩，则它的俯视图是（）A．B．C．D．10、在一些常见的几何体正方体、长方体、圆柱、圆锥、球、圆台、六棱柱、六棱锥中属于柱体有( )A ．3个B ．4个C ．5个D ．6个第Ⅱ卷（非选择题 70分）二、填空题（5小题，每小题4分，共计20分）1、如图是一个多面体的表面展开图，如果面F 在前面，从左面看是面B ，那么从上面看是面___．（填字母，注意：字母只能在多面体外表面出现）2、在长方体1111ABCD A B C D 中，与平面11AA D D 垂直的棱有________条．3、凡与铅垂线重合的直线必与平面_______（填“垂直”或“平行”）．4、一块长方体的木块，从左面和右面分别裁去长为2厘米和5厘米的长方体，成为一个正方体后，表面积减少了84平方厘米，那么原来长方体的体积为_______．5、小强用5个大小一样的正方形制成如图所示的拼接图形（阴影部分），若在图中只添加一个正方形，使新拼接成的图形经过折叠后能成为一个封闭的正方体盒子，这样的拼接方式有_____种．三、解答题（5小题，每小题10分，共计50分）1、有一个长方体的玻璃缸，长、宽、高分别是12厘米、10厘米和8厘米，里面装满了水，现在有一块正方体铁块，边长为6厘米，把它缓慢地浸没在水缸中后再取出，此时玻璃缸中的水面高度是多少？2、把一个长、宽、高分别是12厘米、8厘米、6厘米的长方体铅块和一个棱长是4厘米的正方体铅块一起熔铸成一个长方体，这个长方体的一个面是正方形，边长为4厘米，求长方体内垂直于正方形面的棱长之和．3、如图，在平整的地面上，用8个完全相同的小正方体堆成一个几何体，请画出从三个方向看到的几何体的形状图．4、如图所示，将一个横截面是正方形（面BCGF）的长方体木料，沿平面AEGC（长方形）分割成大小相同的两块，表面积增加了218cm，问原来这30cm，已知EG长5cm，分割后每块木料的体积是3块长方体木料的表面积是多少？5、如图所示，在长方体ABCD EFGH中，写出所有互相平行的平面．-参考答案-一、单选题1、C从正面看所得到的图形即为主视图，注意所有的看到的棱都应表现在主视图中．【详解】解：从正面看易得第一层有3个正方形，第二层最左边有一个正方形，右边是一个三角形．故选：C．【点睛】本题考查了三视图的知识，主视图是从物体的正面看得到的视图．2、C【分析】根据正方体、圆柱、三棱柱表面展开图的特点解题．【详解】解：观察图形，由立体图形及其表面展开图的特点可知相应的立体图形顺次是正方体、圆柱、三棱柱．故选：C．【点睛】本题考查正方体、圆柱、三棱柱表面展开图，记住这些立体图形的表面展开图是解题的关键．3、B【分析】正方体的表面展开图，相对的面之间一定相隔一个正方形，根据这一特点即可作答．【详解】解：正方体的表面展开图，相对的面之间一定相隔一个正方形，“美”与“逆”是相对面．故选：B．本题主要考查了正方体相对两个面上的文字，注意正方体的空间图形，从相对面入手，分析及解答问题．4、B【分析】根据面动成体的原理：将一个等腰三角形绕它的底边旋转一周得到的几何体为两个底面相等的圆锥．【详解】解：将一个等腰三角形绕它的底边旋转一周得到的几何体为两个底面相等的圆锥故选：B．【点睛】此题主要考查几何体的形成，解决本题的关键是掌握各种面动成体的体的特征．5、A【分析】根据左视图是从左面看到的视图判定则可．【详解】解：从左边看，是左右边各一个长方形，大小不同，故选A．【点睛】本题考查了三视图的知识，左视图是从物体的左面看得到的视图．6、D【分析】找出简单几何体的俯视图，对照四个选项即可得出结论．【详解】解：从上面向下看，从左到右有两列，且其正方形的个数分别为3、2，故选：D．【点睛】此题主要考查三视图，解题的关键是熟知俯视图的定义．7、B【分析】得到多面体的棱数，求得面数即为x＋y的值．【详解】解：∵有24个顶点，每个顶点处都有3条棱，两点确定一条直线；∴共有24×3÷2＝36条棱，那么24＋F−36＝2，解得F＝14，∴x＋y＝14．故选B．【点睛】本题考查多面体的顶点数，面数，棱数之间的关系及灵活运用．难点是熟练掌握欧拉定理．8、A【分析】作出该几何体的三视图，根据三视图的面积求解即可．【详解】解：该几何体的三视图为：可得出主视图与俯视图的面积相等．故选：A．【点睛】本题考查了简单组合体的三视图，解答本题的关键在于熟练掌握三视图的概念，并能找出正确的三视图．9、C【分析】找到从上面看所得到的图形即可，注意所有的看到的棱都应表现在三视图中．【详解】解：本题的几何体是一个圆台，它的俯视图是没画圆心的两个同心圆．故选：C．【点睛】本题考查了三视图的知识，俯视图是从物体的上面看得到的视图．10、B【分析】根据立体图形的定义即可解答;【详解】正方体、长方体、圆柱、六棱柱是柱体;圆锥、六棱锥是椎体;球是球体;圆台是台体．故答案为:B【点睛】此题考查立体图形的认识，掌握认识立体图形是解答本题的根本．二、填空题1、E【分析】由多面体的表面展开图特点即可得．【详解】由题意可知，该图形是一个长方体的表面展开图，A面对应F面，B面对应D面，C面对应E面，∵面F在前面，面B在左面，∴面A在后面，面D在右面，E在上面，C在下面，故答案为：E．【点睛】本题考查了几何体的展开图，熟练掌握几何体的展开图特点是解题关键．2、4【分析】长方体中的棱与面的关系有2种：平行和垂直，结合图形可找到与面AA D D垂直的棱．【详解】解：如图示：根据图形可知与面AA D D 垂直的棱有AB ，CD ，C D ''，A B ''共4条．故答案是：4．【点睛】主要考查了长方体中的棱与面之间的位置关系．要知道长方体中的棱的关系有2种：平行和垂直．3、垂直【分析】根据铅垂线法可直接作答．【详解】因为凡与铅垂线重合的直线必与平面垂直；故答案为垂直．【点睛】本题主要考查长方体中棱与面的位置关系，熟练掌握位置关系解题的关键．4、90立方厘米【分析】设正方体棱长为x 厘米，根据题意列方程可求得x 的值，进而得到原长方体的长、宽、高的值，再计算体积即可.【详解】设正方体棱长为x 厘米，依题意得245484x x ⋅⋅+⋅⋅=，解得3x =，则原长方体的宽为3厘米，高为3厘米，长为32510++=厘米，则331090V =⨯⨯=立方厘米．【点睛】此题主要考查长方体的表面积公式、体积公式的灵活运用，解题的关键是熟记公式．5、3【分析】结合正方体的平面展开图的特征，只要折叠后能围成正方体即可．【详解】解：根据正方体的表面展开图可得共有3种，如图：【点睛】此题主要考查了正方体的平面展开图，应灵活掌握，不能死记硬背．三、解答题1、6.2厘米【分析】根据长方体的体积计算即可；【详解】()()-⨯⨯÷⨯=（厘米）；86661210 6.2答：此时玻璃缸中的水面高度是6.2厘米．【点睛】本题主要考查了长方体的再认识，准确计算是解题的关键．2、160厘米【分析】根据长方体的棱长计算即可；【详解】熔铸成长方体的体积：1286444640⨯⨯+⨯⨯=（立方厘米），∴44640h ⨯⨯=，解得40h =，则垂直于正方形面的棱长之和为404160⨯=（厘米）．【点睛】本题主要考查了长方体棱与棱的位置关系和长方体的认识，准确计算是解题的关键．3、画图见解析【分析】根据三视图的定义画出图形即可．【详解】解：三视图如图所示：【点睛】本题考查作图-三视图，解题的关键是建立空间观念，正确画出图形．4、366cm【分析】根据对角线所在长方形的面积面积求法可得出CG ，即可得到体积；【详解】由题意：长方形AECG 的面积为215cm ，所以1553cm CG =÷=．又因为横截面是正方形，故3cm BC CG ==．而其体积为318236cm ⨯=，所以36334cm AB =÷÷=．原来这块长方体木料的表面积为()2434333266cm ⨯+⨯+⨯⨯=． 答：原来这块长方体木料的表面积是366cm ．【点睛】本题主要考查了长方体的认识，准确计算是解题的关键．5、互相平行的平面有：面ABCD 与面EFCH 、面ADHE 与面BCGF 、面ABFE 与面DCGH【分析】根据长方体的特征相对面平行，进行解答即可．【详解】面ABCD 与面EFCH 、面ADHE 与面BCGF 、面ABFE 与面DCGH【点睛】本题主要考查长方体的特征，熟练掌握棱与面的位置关系：12条棱分为互相平行的3组，每组4条棱的长度相等，6个面都是长方形（特殊情况有两个相对的面是正方形），相对的面的面积相等．。