上海民办新竹园中学九年级2019学年第一学期期中考卷及答案
2019学年第一学期九年级期中卷答案

2019学年第一学期九年级期中考试(科学)(参考答案和评分标准)一.选择题(本题有15小题,每小题3分,共45分。
请选出一个符合题意的正确选项,不选、多选、错选均不给分)二.填空题(本题有9小题24空格,每空格2分,共48分)16. (1) C (2) 1:117. (1) Na + Cl - (2) H + + OH -= H 2O 18. 酚酞变红色 >19. (1) 2NaOH+ZnSO 4=Zn(OH)2↓+Na 2SO 4 (或 2NaOH+FeSO 4= Fe (OH)2↓+Na 2SO 4)(2) Na 2SO 4 、 NaOH 、 MgSO 4 (不全不给分)20. (1)2KMnO 4 Δ K 2MnO 4 + MnO 2 + O 2↑ ( 或 2KClO ↑+=∆23322O KCl O M n )(2) A b21. (1)R+2HCl =RCl 2+H 2↑ (2)Ag 、Cu 、R (不全不给分) (3) 可能22. (1)白色固体(硫酸铜)变蓝 硝酸银溶液(或紫色石蕊试液) BC(2) 浓硫酸23. (1) 放热 (2) 蓝 NaCl (3) 减小24. (1) 氢氧化钾、稀硫酸 (2) 氯化氢、氯化钡、氯化镁三、实验探究题(本题4小题,25、26题每格2分,27、28每格3分共36分)25. (1) ① 木块被推动的距离 (2) <26. ⑴水分子(或H 2O ); 双氧水是水溶液,所以水不是催化剂(意思对即可)⑵SO 42-(或硫酸根离子) CuCl 2(或氯化铜) Cu 2+(或铜离子) (3)化学性质和质量都没有改变 (答全才给分) 27. 主题Ⅰ (1) 判断杂质中是否含有氯化镁 (2)不同意 ,加入稀盐酸要排除碳酸钠的干扰主题Ⅱ 92.9%28. (1) 2.2 (2) 氧化钙:16.6g; 碳酸钙:5g; 氢氧化钙:7.4g( 完整答全1个给1分 )(3)氧化钙能和空气中的水反应生成氢氧化钙,氢氧化钙能和空气中的二氧化碳生成碳酸钙 (只答对1条给1分)四.解答题(共3小题,第29题6分,第30题10分,第31题15分共31分)29.(1) b (2) 2.2 (每空3分共6分) 30.(1)6.991.02 (2)不合格 ( 每空2分 共6分)(3)氢氧化钡的质量分数为y 。
上海市2019学年第一学期九年级期中考试英语试卷(含题目答案和答题纸)

上海市2019学年第一学期九年级期中考试英语试卷(满分:150分,考试时间:100分钟)2019.11 考生注意:本卷共有94题。
请将所有答案写在答题卷上,写在试卷上不计分。
Part One Listening (第一部分听力)I. Listening Comprehension (听力理解) (共30分)A. Listen and choose the right picture (根据你听到的内容,选出相应的图片) (共6分)A B C DE F G H1.______2. ______3. ______4. ______5. ______6. ______B. Listen to the dialogue and choose the best answer to the question you hear (根据你听到的对话和问题,选出最恰当的答案) (共8分)7. A. By bike. B. On foot. C. By bus. D. By car.8. A. His sister. B. His mother. C. His brother. D. His father.9. A. Red. B. Blue. C. Black. D. Orange.10. A. Father and daughter. B. Doctor and patient.C. Teacher and student.D. Customer and student.11. A. To the library. B. To the playground.C. To the bookstore.D. To the supermarket.12. A. Because he had a headache. B. Because he drank a lot of wine.C. Because he watched TV too long.D. Because he drank too much Coke.13. A. 3:20. B. 3:40. C. 4:00 D. 4:2014. A. The food there was delicious. B. The food there was not bad.C. The food there was tasty and cheap.D. The food there was terrible.C. Listen to the passage and tell whether the following statements are true or false (判断下列句子是否符合你听到的短文内容, 符合的用“T”表示,不符合的用“F”表示) (共6分)15. The charity organization was created by an Australian girl.16. The organization buys and sells bikes people no longer use.17. Each bike will be checked up carefully before it is given out.18. Students who have good grades and behave well can receive the bikes as a prize.19. The charity organization is welcomed by parents and teachers.20. Because of the bikes, many students are not only good at school work but also good at cycling.D. Listen to the passage and fill in the blanks (听短文填空,完成下列句子。
上海版2019届九年级上学期英语期中考试试卷(II )卷

上海版2019届九年级上学期英语期中考试试卷(II )卷一、单项填空 (共15题;共30分)1. (2分)My father is not going to Beijing by plane. Instead, he is taking trainA . /;aB . a;/C . a theD . the, a2. (2分)— Why are you walking so quickly, Edward?— There __________ a talent show in ten minutes.A . will haveB . will beC . is going to haveD . are going to be3. (2分)– Don't throw plastic bags towards the animals in the zoo.-- _____A . All rightB . My pleasureC . Not at allD . Don't mention.4. (2分)—How long can I _____ the Chinese workbook?—For three weeks.A . borrowB . keepC . to borrowD . to keep5. (2分)What a day! The car I ___________ seems to go wrong again.A . have repaired itB . had repairedC . had repaired itD . have it repaired6. (2分)Don't worry. We will do something you.A . helpB . helpingC . helpedD . to help7. (2分)-- Are all the titles of the articles ______ in the contents?--Yes, all ______.A . listed; includedB . listing; includesC . listed; includingD . being listed; being included8. (2分)—Hi, John! Would you like to go hiking with me tomorrow?—Sounds great! Hiking is a good way to keep fit.A . livelyB . activeC . healthy9. (2分)—Don't eat in the classroom. You must eat in the dining hall.—_______.A . No, I mustn'tB . Yes, I mustC . I'm sorryD . Excuse me10. (2分)—Are you sure you can do well in the competition? — I've got everything ready.A . No, I'm not sure.B . Yes, I think so.C . It's hard to say.11. (2分)The summer holiday is coming. We're going to have _______ holiday.A . a two-monthB . a two-monthsC . two monthsD . two-months12. (2分)— Do you know the new mobile phone yesterday?—Maybe about 2, 800 yuan. I'm not sure.A . how much she paid forB . how much will she pay forC . how much did she pay forD . how much she will pay for13. (2分)—Which factory produced this radio?—Ben's factory.A . madeB . soldC . collected14. (2分)Sometimes we saw stars _____brightly____ in the sky.A . shoot; throughB . shot; acrossC . shooting; acrossD . shot; cross15. (2分)—Michael, how much do you know about _________?—people usually eat rice dumplings to remember Qu Yuan.A . the Mid-Autumn FestivalB . the Spring FestivalC . the Dragon Boat FestivalD . the Lantern Festival二、完形填空 (共1题;共1分)16. (1分)完形填空Our teacher asked us what our favorite animal was,and I said,”Fried chicken”She said I wasn't funny, but she wasn't1, because everyone else laughed.My parents told me to always be truthful and I am. Fried chicken is my favorite 2. I told my dad what happend, and he said my teacher was probably a(n) 3 of PETA. He said they love animals very much.I do, too. Especially chicken, pork and beef. 4my teacher sent me to the principal's office(校长室).I told him what happened, and he 5 too. Then he told me not to do it again.The next day in class my teacher asked me what my favorite live animal was. I told her it was chicken. She asked me6 just like she'd asked the other children.I told her it was because people could7 them into fried chicken. She sent me back to the principal's office. He laughed, and told me not to do it again. I don't 8. My parents taught me to be honest, 9 my teacher doesn't like it when I am.Today, my teacher asked me to tell her what famous person10 like(s) most.I told her, "Colonel Sanders(肯德基创始人)."Guess where I am now?(1)A . angerB . rightC . patientD . serious(2)A . foodB . animalC . answerD . taste(3)A . exampleB . discoverC . enemyD . member(4)A . InsteadB . AgainC . AnywayD . Also(5)A . laughedB . believedC . shoutedD . agreed (6)A . whenB . whereC . howD . why(7)A . cutB . divideC . makeD . add(8)A . careB . regretC . understandD . remember (9)A . butB . andC . orD . for(10)A . IB . weC . sheD . they三、阅读理解 (共3题;共30分)17. (10分)(B)阅读理解I'm Li Mei and I study in No. 3 Middle School. I live in the school Monday to Friday. I only go home on weekends. I usually go home by bus. It takes about half an hour. Some students go home by bike. We often have some activities in our free time. Peter and Tom often play soccer. Kate and I often go to the school library. Helen often does her homework in the classroom. What does Sally like to do after school? She likes to play ping-pong. We have dinner at about six o'clock. Then we go back to our classroom to study. At half past nine, we usually go to bed. Our teachers are all very good. We are happy in our school.(1)Where does Li Mei live from Monday to Friday?A . In the library.B . In her school.C . At home.D . In the street.(2)How does Li Mei go home?A . By subwayB . By car.C . By bike.D . By bus..(3)Howlong does it take Li Mei to get home from her school by bus?A . About 30 minutes.B . About 20 minutes.C . About 15 minutes.D . About one hour.(4)Who does Li Mei often go to the school library with after school?A . Helen.B . KateC . Sally.D . Peter.(5)What time do they usually go to bed?A . At 8:30 a.m.B . At 8:30 p.m.C . At 9:30 p.m.D . At 9:30 a.m.18. (10分)阅读下面材料,然后从各题所给的四个选项中选出一个最佳答案。
2019届上海市九年级上学期期中化学试卷【含答案及解析】(1)

2019届上海市九年级上学期期中化学试卷【含答案及解析】姓名___________ 班级____________ 分数__________一、选择题1. 下列变化属于化学变化的是()A.铁钉生锈 B.湿衣服晒干 C.矿石粉碎 D.蜡烛受热融化2. 用分子的观点解释下列现象,错误的是()A.热胀冷缩﹣﹣分子大小随温度的变化而改变B.花香四溢﹣﹣分子不停地运动C.食物腐败﹣﹣分子发生变化D.酒精挥发﹣﹣分子间间隔变大3. 下列叙述错误的是()A.分子是保持物质化学性质的一种微粒B.分子能构成物质,原子也能直接构成物质C.化学反应的实质就是原子的重新组合D.由同种元素组成的物质一定是纯净物4. “乐百氏”矿泉水标签上印有水质成分如下(mg/L):硒:0.013;锶:0.0596;锌:0.00162;钠:18.4;钙:4.69.这里的硒、锶、锌、钠、钙是指()A.元素 B.原子 C.单质 D.分子5. 下列物质中,属于混合物的是()A.氧化铝 B.澄清的石灰水 C.冰水混合物 D.水银6. 下列物质中,硫元素的化合价为+6价的是()A.H 2 SO 3 B.SO 2 C.SO 3 D.H 2 S7. 下列试剂瓶标签上的化学式书写错误的是()A. B. C. D.8. 如图是表示气体分子的示意图,图中“ ”和“ ”分别表示两种不同质子数的原子,其中表示单质的是()A. B. C.D.9. 隐形眼镜洗液有效成分是过氧化氢(H 2 O 2 ),有关过氧化氢正确的是() A.它由氢气和氧气组成B.它由氢元素和氧元素组成C.它由1个氢分子和1个氧分子构成D.它由2个氢原子和2个氧原子组成10. 汽车安全气囊内所装化学物质,能在碰撞后10毫秒内,生成一种空气中含量最多的气体,该气体是()A.氮气 B.氧气 C.二氧化碳 D.稀有气体11. 下列实验操作正确的是()A.在量筒内进行化学反应B.用剩的药品放回原瓶C.用燃着的酒精灯去点燃另一个酒精灯D.点燃氢气前必须检验其纯度12. 在实验室加热100ml液体时必须使用的仪器是()①烧杯②试管③酒精灯④石棉网⑤试管夹⑥带铁圈的铁架台.A.②③⑤ B.①⑤⑥ C.①③④⑥ D.②③⑤⑥13. 下列各组仪器,能加热的一组是()A.烧杯、试管、量筒 B.试管、烧杯、蒸发皿C.烧杯、蒸发皿、集气瓶 D.蒸发皿、集气瓶、量筒14. 下列各种含碳的化合物中,碳元素的质量百分含量最少的是()A.CO 2 B.H 2 CO 3 C.CaCO 3 D.C 6 H 12 O 615. 能鉴别H 2 、O 2 、N 2 和空气四种无色气体最简便的方法是()A.用燃着的木条 B.用澄清石灰水C.用硝酸银溶液 D.用紫色的石蕊试液二、填空题16. 下列现象说明空气中存在着某气体物质,请将物质的名称(或化学式)写在题后空格内.(1)人体中含量最多的金属元素是,(2)地壳中含量最多的元素为;(3)用来充飞艇的一种既安全密度又小的气体;(4)利用空气制造氮肥,说明空气中含有;(5)澄清石灰水长期露置在空气中,瓶壁和石灰水底部均会出现白色固体物质,说明空气中含有;(6)木炭在空气中燃烧,说明空气中含有;(7)夏天从冰箱里拿出一瓶饮料,放在空气中,饮料外壁会潮湿,说明空气中含有.17. 回答下列问题:(1)实验时应严格按实验规定的用量取用药品.如果没有说明用量,一般应按最少量取用:液体 mL,固体只需.(2)如果要量取6mL液体,所需的仪器是①10mL量筒②20mL量筒③100mL量筒④滴管A.① B.①④ C.②④ D.③④(3)洗过的玻璃仪器内壁附着的水既不,也不时,表示仪器已洗干净.(4)某同学用托盘天平称量11.6g固体粉末时,错将砝码放在左盘,将药品放在了右盘.该同学实际称得药品的质量为 g.(1g以下用游码)18. 极少数青年有吸烟的有害健康行为.香烟经燃烧产生烟气中含许多强致癌物和其他有害物,如尼古丁(C 10 H 14 N 2 )、焦油、一氧化碳等.其中尼古丁是由种元素组成的.每个尼古丁分子中共含有个原子,其中碳原子、氢原子、氮原子的个数比为,其相对分子质量为.19. 元素R的氯化物RCl 3 ,若R的化合价不变,它与氧元素形成的化合物的化学式是;若R的氧化物是RO n ,则它的氯化物的化学式是.20. 在下列空格中写出有关的化学符号或表示的意义:p21.化学符号2N2H 2 O 表示意义 3个氢分子 <p>22. 在下列空格中写出相应物质的名称或化学式:p23. 物质名称氧化钠一氧化碳化学式 FeCl 2 Ne <p>24. 如图,灯焰处a为,b为,c为.把一根火柴梗横放在酒精灯的火焰中,1﹣2秒后取出,观察到火柴梗在处(填a、b、c)的部分最先碳化(变黑),说明.试解释家用煤气炉上都有一个高低适宜的放锅三角架?.25. 现有如图1的实验仪器:(1)指出图1中标有数字的仪器名称:① ② ③ ④(2)不管选择装置A还是B做有关气体的实验,实验过程中必须首先进行的操作是.(3)实验室用氯酸钾制取氧气所用的发生装置是,(用序号表示,以下同),收集氧气的装置用(选填其中一个),原因是.(4)如用上题中你选择的收集方法,那么怎样证明氧气是否收集满呢?(写出实验步骤、现象和结论).(5)他们用该装置收集满两瓶氧气,并按图2所示进行实验,用带火星的木条分别以甲、乙两种方式迅速伸入,发现木条复燃,且在甲中燃烧比在乙中更旺.上述实验说明了氧气具有的性质是:① ②(6)已知在通常状况下,一氧化氮是一种难溶于水无色气体,它的密度与空气相近;一氧化氮很容易与氧气化合,生成二氧化氮气体.所以在实验室里我们常用(用序号表示)法收集一氧化氮.三、计算题26. 根据化学式进行有关的计算:(1)硝酸铵NH 4 NO 3 中含氮元素的质量百分含量?(2)多少千克硝酸铵所含氮元素质量与60千克尿素CO(NH 2 ) 2 含氮元素质量相等?参考答案及解析第1题【答案】第2题【答案】第3题【答案】第4题【答案】第5题【答案】第6题【答案】第7题【答案】第8题【答案】第9题【答案】第10题【答案】第11题【答案】第12题【答案】第13题【答案】第14题【答案】第15题【答案】第16题【答案】第17题【答案】第18题【答案】第19题【答案】第20题【答案】第21题【答案】第22题【答案】第23题【答案】第24题【答案】。
【物理】上海民办新竹园中学九年级上册期中精选试卷检测题

【物理】上海民办新竹园中学九年级上册期中精选试卷检测题一、初三物理电流和电路易错压轴题(难)1.现有两只小灯泡L1、L2,它们的额定电压分别为2.5V和3.8V.(1)如图甲是小明测定灯泡L1额定功率的实物电路图(不完整).①请用笔画线代替导线将实物电路图连接完整_____.②闭合开关前,应将滑动变阻器的滑片P移到__端(选填“A”或“B”).闭合开关后发现:小灯泡不亮,电流表示数为零,而电压表示数接近电源电压。
经检查,电流表是完好的,仅滑动变阻器或小灯泡存在故障,则电路中的故障是__.排除故障后,闭合开关,仍发现小灯泡不亮,电流表指针偏转很小,要使该小灯泡发光只需__。
③当电压表示数为2.5V时,电流表示数如图乙所示,则灯泡L1的额定功率为__W.(2)小华利用图丙所示的电路测出了灯泡L2的额定功率.图中R为阻值已知的定值电阻,还缺两个开关和一只电表(电流表或电压表),请在虚线框内补上这三个元件的符号,使电路完整,实验操作简单______.【答案】A灯泡断路移动滑动变阻器0.8【解析】(1)①根据图中电表的正、负接线柱,从电源正极连接开关,滑动变阻器的接线柱要求一上一下的串联在电路中,所以将C或D连到电源负极即可,如下图所示:②电压表有示数,说明电压表与电源连通;电流表示数几乎为零,灯泡不发光,说明电路断路或电路的总电阻很大,导致这一现象的原因可能是小灯泡断路而导致电压表串联在电路中;③为了保护电路,闭合开关前,滑片P应处在使电路中电阻最大位置A端;由乙图,电流表使用0-0.6A量程,分度值为0.02A,示数为0.32A,所以灯泡L1的额定功率:;(2)由上面的分析知,右上边的是电压表;左边两虚线框内是开关,如图所示:①只闭合S和中间的开关,移动滑片使电压表示数为3.8V;②保持滑片位置不动,断开中间开关,闭合左上边开关,测出灯与R的总电压,根据串联电路的电压特点计算出R两端电压U R;③由计算出R的电流,即灯泡此时的电流,由P=U额I额计算灯泡L2电功率即可.故答案为:(1). (2). A (3). 灯泡断路 (4). 移动滑动变阻器(5). 0.8 (6).【点睛】本题是测灯泡额定功率的实验,考查了电路连接、变阻器的使用、电表读数和功率计算以及特殊方法测功率的电路设计.特殊方法测功率时,只给电流表通常会使用并联电路,只给电压表时通常使用并联电路,利用已知阻值的电阻与电表的组合间接测电压或电流达到实验目的。
沪科版2019-2020学年九年级数学第一学期期中试题(含答案)

沪科版2019-2020学年九年级数学第一学期期中试题(含答案)本卷满分150分,考试时间120分钟一.选择题(50分)1.抛物线y =﹣3x 2+6x +2的对称轴是( ) A .直线x =2 B .直线x =﹣2 C .直线x =1 D .直线x =﹣1 2.已知5x =6y (y ≠0),那么下列比例式中正确的是( ) A . B . C . D . 3.已知点A (1,﹣3)关于x 轴的对称点A ' 在反比例函数y =的图象上,则实数k 的值为( ) A .3 B . C .﹣3 D .﹣ 4.已知二次函数)2(2-++=m m x mx y 的图象经过原点,则m 的值为 ( ) A . 0或2 B . 0 C . 2 D .无法确定 5.关于反比例函数y =﹣的图象,下列说法正确的是( ) A .经过点(﹣1,﹣4) B .当x <0时,图象在第二象限 C .无论x 取何值时,y 随x 的增大而增大 D .图象是轴对称图形,但不是中心对称图形 6.如图,已知点C 是线段AB 的黄金分割点,且BC >AC .若S 1表示以BC 为边的正方形面积,S 2表示长为AB 、宽为AC 的矩形面积,则S 1与S 2的大小关系为( )A .S 1>S 2B .S 1=S 2C .S 1<S 2D .不能确定7.如图,一张矩形纸片ABCD 的长AB =a ,宽BC =b .将纸片对折,折痕为EF ,所得矩形AFED 与矩形ABCD 相似,则a :b =( )A .2:1 B .:1 C .3: D .3:2班级_______________ 姓名_______________ 号码_______________8.正比例函数y1=k1x的图象与反比例函数y2=的图象相交于A,B两点,其中点B的横坐标为﹣2,当y1<y2时,x的取值范围是()A.x<﹣2或x>2B.﹣2<x<0或x>2C.﹣2<x<0或0<x<2D.x<﹣2或0<x<29.下列4×4的正方形网格中,小正方形的边长均为1,三角形的顶点都在格点上,则与△ABC相似的三角形所在的网格图形是()A B C D10.如图,∠ABC=∠CDB=90°,BC=3,AC=5,如果△ABC与△CDB相似,那么BD的长( )A.B.C.D.或二、填空题(20分)11.若,则=.12.在广安市中考体考前,某初三学生对自己某次实心球训练的录像进行分析,发现实心球飞行高度y(米)与水平距离x(米)之间的关系为y=﹣x2+x+,由此可知该生此次实心球训练的成绩为.13.如图,梯形ABCD中,AD∥BC,AC交BD于点O.若S△AOD=4,S△AOB=6,则△COD的面积是.14.如图,直线l⊥x轴于点P,且与反比例函数y1=(x>0)及y2=(x>0)的图象分别交于点A、B,连接OA,OB,已知△OAB的面积为1,则k1﹣k2=.三、解答题(16分)15.已知抛物线y=ax2+bx﹣3(a≠0)经过点(﹣1,0),(3,0),求a,b的值.16.已知二次函数的图象经过点P(2,2),顶点为0(0,0),将该图象向右平移,当它再次经过点P时,求所得抛物线的函数表达式.四、(20分)17.如图,延长△ABC的边BC到D,使CD=BC,取AB中点F,边DF交AC于E,求的值.18.阅读与计算,请阅读以下材料,并完成相应的问题.角平分线分线段成比例定理,如图1,在△ABC中,AD平分∠BAC,则=.下面是这个定理的部分证明过程.证明:如图2,过C作CE∥DA.交BA的延长线于E.…任务:(1)请按照上面的证明思路,写出该证明的剩余部分;(2)填空:如图3,已知Rt△ABC中,AB=3,BC=4,∠ABC=90°,AD平分∠BAC,则△ABD的周长是.五、(20分)19.如图是反比例函数y=的图象,当﹣4≤x≤﹣1时,﹣4≤y≤﹣1.(1)求该反比例函数的解析式;(2)若M、N分别在反比例函数图象的两支上,请指出什么情况下线段MN最短(不需证明),并求出线段MN长度的取值范围.20.已知,△ABC在直角坐标系内,三个顶点的坐标分别为A(0,3),B(3,4),C(2,2)(正方形网格中每个小正方形的边长均为一个单位长度).(1)画出△ABC向下平移4个单位长度得到的△A1B1C1,点C1的坐标是______________;(2)以点B为位似中心,在网格内画出△A2B2C2,使△A2B2C2与△ABC位似,且位似比为2:1,点C2的坐标是______________;(3)求△A2B2C2的面积是__________平方单位.六、(本题满分12分)21.“疾驰臭豆腐”是长沙知名地方小吃,某分店经理发现,当每份臭豆腐的售价为6元时,每天能卖出500份;当每份臭豆腐的售价每增加0.5元时,每天就会少卖出20份,设每份臭豆腐的售价增加x元时,一天的营业额为y元.(1)求y与x的函数关系式(不要求写出x的取值范围);(2)考虑到顾客可接受价格a元/份的范围是6≤a≤9,且a为整数,不考虑其他因素,则该分店的臭豆腐每份多少元时,每天的臭豆腐营业额最大?最大营业额是多少元?七、(本题满分12分)22.如图,直线l:y=﹣3x+3与x轴、y轴分别相交于A、B两点,抛物线y=ax2﹣2ax+a+4(a<0)经过点B.(1)求该抛物线的函数表达式;(2)已知点M是抛物线上的一个动点,并且点M在第一象限内,连接AM、BM,设点M的横坐标为m,△ABM的面积为S,求S与m的函数表达式,并求出S的最大值;(3)在(2)的条件下,当S取得最大值时,动点M相应的位置记为点M′.写出点M′的坐标.期中数学试卷参考答案一、选择题1.C.2.B.3.A.4.C.5.B.6.B.7.B.8.D.9.B 10.D二、填空题11..12.10米13.6.14.如图,直线l⊥x轴于点P,且与反比例函数y1=(x>0)及y2=(x>0)的图象分别交于点A、B,连接OA,OB,已知△OAB的面积为1,则k1﹣k2=2.【解答】解:设点A坐标为(a,b)则ab=k1∴S△AOP=同理S△BOP=∵S△AOB=S△AOP﹣S△BOP=∴k1﹣k2=2故答案为:2三、解答题15.a的值是1,b的值是﹣2.16.已知二次函数的图象经过点P(2,2),顶点为0(0,0),将该图象向右平移,当它再次经过点P时,求所得抛物线的函数表达式.【解答】解:设原来的抛物线解析式为:y=ax2(a≠0).把P(2,2)代入,得2=4a,解得a=.故原抛物线解析式是:y=x2.设平移后的抛物线解析式为:y=(x﹣b)2.把P(2,2)代入,得2=(2﹣b)2.解得b=0(舍去)或b=4.所以平移后抛物线的解析式是:y=(x﹣4)2.四、解:过点C作CM∥AB,∵CD=BC,CM∥AB,∴CM BF,∵AB中点F,∴AF=BF,∴CM AF,∴△AFE∽△CME,∴==,∴=.18.阅读与计算,请阅读以下材料,并完成相应的问题.角平分线分线段成比例定理,如图1,在△ABC中,AD平分∠BAC,则=.下面是这个定理的部分证明过程.证明:如图2,过C作CE∥DA.交BA的延长线于E.…任务:(1)请按照上面的证明思路,写出该证明的剩余部分;(2)填空:如图3,已知Rt△ABC中,AB=3,BC=4,∠ABC=90°,AD平分∠BAC,则△ABD的周长是【解答】(1)证明:如图2,过C作CE∥DA.交BA的延长线于E,∵CE∥AD,∴=,∠2=∠ACE,∠1=∠E,∵∠1=∠2,∴∠ACE=∠E,∴AE=AC,∴=;(2)解:如图3,∵AB=3,BC=4,∠ABC=90°,∴AC=5,∵AD平分∠BAC,∴=,即=,∴BD=BC=,∴AD===,∴△ABD的周长=+3+=.故答案为.五、19.如图是反比例函数y=的图象,当﹣4≤x≤﹣1时,﹣4≤y≤﹣1.(1)求该反比例函数的解析式;(2)若M、N分别在反比例函数图象的两支上,请指出什么情况下线段MN最短(不需证明),并求出线段MN长度的取值范围.解:(1)∵在反比例函数的图象中,当﹣4≤x≤﹣1时,﹣4≤y≤﹣1,∴反比例函数经过坐标(﹣4,﹣1),将坐标代入反比例函数y=中,得反比例函数的解析式为y=(2分);(2)当M,N为一,三象限角平分线与反比例函数图象的交点时,线段MN最短.将y=x代入,解得,即M(2,2),N(﹣2,﹣2).∴OM=2.则MN=4.又∵M,N为反比例函数图象上的任意两点,由图象特点知,线段MN无最大值,即MN≥4.20.17.解答:(1)如图所示,C 1(2,-2);(2)如图所示,C 2(1,0);(3)∵A 2C 22=20,B 2C 22=20,A 2B 22=40,∴A 2C 22=B 2C 22,且A 2C 22+ B 2C 22=A 2B 22,∴△△A 2B 2C 2是等腰直角三角形,∴△A 2B 2C 2的面积是1210(平方单位).六、(本题满分12分)21.“疾驰臭豆腐”是长沙知名地方小吃,某分店经理发现,当每份臭豆腐的售价为6元时,每天能卖出500份;当每份臭豆腐的售价每增加0.5元时,每天就会少卖出20份,设每份臭豆腐的售价增加x 元时,一天的营业额为y 元.(1)求y与x的函数关系式(不要求写出x的取值范围);(2)考虑到顾客可接受价格a元/份的范围是6≤a≤9,且a为整数,不考虑其他因素,则该分店的臭豆腐每份多少元时,每天的臭豆腐营业额最大?最大营业额是多少元?【解答】解:(1)由题意得:y=(500﹣×20)(6+x)=(x+6)(500﹣40x);(2)6≤a≤9,即0≤x≤3,y=(x+6)(500﹣40x)=﹣40(x+6)(x﹣12.5),函数的对称轴为:x=6.5,∵﹣40<0,函数有最大值,当x<6.5时,函数随x的增大而增大,而0≤x≤3,故x=3时,y最大,此时,y最大值为:3420,即每份9元时,营业额最大,最大营业额是3420元.七、(本题满分12分)22.如图,直线l:y=﹣3x+3与x轴、y轴分别相交于A、B两点,抛物线y=ax2﹣2ax+a+4(a<0)经过点B.(1)求该抛物线的函数表达式;(2)已知点M是抛物线上的一个动点,并且点M在第一象限内,连接AM、BM,设点M的横坐标为m,△ABM的面积为S,求S与m的函数表达式,并求出S的最大值;(3)在(2)的条件下,当S取得最大值时,动点M相应的位置记为点M′.写出点M′的坐标.解:(1)直线l:y=﹣3x+3与x轴、y轴分别相交于A、B两点,则点A、B的坐标分别为:(1,0)、(0,3),抛物线y=ax2﹣2ax+a+4(a<0)经过点B(0,3),则a+4=3,解得:a=﹣1,故抛物线的表达式为:y=﹣x2+2x+3;(2)过点M作MH⊥x轴于点H,设点M(m,﹣m2+2m+3),则S=S梯形BOHM﹣S△OAB﹣S△AMH=(﹣m2+2m+3)×m﹣[3×1+(m﹣1)(﹣m2+2m+3)]=﹣m2+m ﹣,∵0,故S有最大值,当m=时,S的最大值为:;(3)当S取得最大值时,此时,m=,则y=﹣m2+2m+3=,故点M′的坐标为:(,).。
2019-2020学年上海市浦东新区新竹园中学九年级(上)月考数学试卷(9月份)-解析版
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上海版2019届九年级上学期英语期中考试试卷A卷
上海版2019届九年级上学期英语期中考试试卷A卷一、单项填空 (共15题;共30分)1. (2分)My friend Amy often takes walk with her dog in the park after dinner.A . 不填B . aC . anD . the2. (2分)Listen! Someone_____ singing in the next room.A . isB . areC . doesD . do3. (2分)—Can't you go to the cinema with us?—_________. I have to look after my mother. She is ill in bed.A . No, I doB . I'm afraid notC . Yes, I doD . Yes, I don't4. (2分)—Must I finish my homework this morning?—No, you ___________. You can finish it this afternoon.A . mustn'tB . couldn'tC . needn'tD . can't5. (2分)—What _______ you just now?—Don't worry. Nothing _______.A . has happens to; has happenedB . happened; happenedC . happened; has happenedD . happened to; has happened6. (2分)—Everyone should help save the planet.—Yeah. I've stopped ________ plastic bags when shopping.A . to useB . usingC . useD . used7. (2分)Yesterday it snowed. Now the roads ___________ still ___________ snow.A . be; covered withB . were; covered byC . are; covered withD . are; covered for8. (2分)When you're _________, you should listen to music that can make you happy.A . shyB . afraidC . strictD . down9. (2分)—Nice to meet you,Alan!—______A . I'm fine,thanks.B . Nice to meet you,too!C . Hello!D . Good morning!10. (2分)——_ ___?-——No problem.A . Did you have a penB . What time did you get up this morningC . Could you help me with houseworkD . How often do you visit your parents11. (2分)The summer holiday is coming. We're going to have _______ holiday.A . a two-monthB . a two-monthsC . two monthsD . two-months12. (2分)—Excuese me, can you tell me _____________?—Sorry, I'm new here.A . how can I get to the parkB . which is the way to the bankC . where is the nearest bankD . is there a bank near here13. (2分)The floor requires cleaning.A . makesB . needsC . accepts14. (2分)_________________ ill, I can't go to school today.A . Because ofB . AsC . BeingD . With15. (2分)- Michael, how much do you know about _________?- People usually eat rice dumplings to remember Qu Yuan.A . the Mid-Autumn FestivalB . the Spring FestivalC . the Dragon Boat FestivalD . the Lantern Festival二、完形填空 (共1题;共1分)16. (1分)先通读下面的短文,掌握其犬意,然后从A B C D四个选项中选择可以填入空白处的最佳答案Devon Miller put the bag onto his back."Did you take the water?" asked his dad."Yes," said Devon."How about the bread? And the map?""Don't worry. I put 1 m my bag, Dad," Devon said. "Come on. Let's go!"Devon couldn't wait to start the hike (徒步旅行). It was 2 and Devon expected (期待) a good, long hike. Mr. Miller3a little, because it was his first hiking trip. Usually Devon's mom took him, 4 today she had to work. So Devon's dad decided to have a try."Where do we start?" his dad asked." 5 that tree with the yellow mark (记号)? That's the start of a small road. We just 6 the marks on the trees along the road. The small road goes in a big circle (圆圈). We'll 7 here in a few hours."Mr. Miller tried to smile. "Sounds like 8 !"Devon and his dad started their hike. It was a beautiful spring day. The weather was cool, but not very cold. They walked and walked. Then they stopped and ate their bread 9 lunch.Mr. Miller seemed a lot more relaxed. "This is fun. I'll go hiking with you 10 anytime," he said.(1)A . anythingB . somethingC . everythingD . nothing(2)A . springB . summerC . autumnD . winter(3)A . wonderedB . worriedC . waitedD . surprised(4)A . becauseB . ifC . orD . but(5)A . LookB . SeeC . WatchD . Read(6)A . followB . drawC . showD . brush(7)A . come backB . get lostC . call backD . get dressed (8)A . dreamB . luckC . funD . danger (9)A . withB . atC . aboutD . for(10)A . tooB . againC . alsoD . either三、阅读理解 (共3题;共30分)17. (10分)阅读理解Bill is a student. He is twelve. The child likes to fly kites and play some other games.One Monday afternoon Bill flies kites with his friends after school. But Bill's kite is in the tree and he cannot get it. Bill and his friends do not know what to do. They worry very much and Bill comes to his father, Mr. Green, for help. His father wants to get the kite down from the tree, but he can't. So Bill asks him to make a new one for him. Mr. Green makes a new kite for Bill. When the boy gets the new kite, he is very glad. He thanks his father for the kite and goes out to play with his friends.(1)How many children are there in Mr. Green's family?A . We don't know.B . Three.C . One.D . Two.(2)Bill likes to ___.A . play gamesB . make kitesC . fly kites onlyD . play other games and fly kites(3)One day ____.A . Bill makes a kite for his friendsB . Bill's friends mend his kiteC . Bill's kite is in the treeD . Bill finds a kite in a tree(4)Bill is glad because(因为) ____.A . Mr. Green makes a new kite for himB . his father helps him get the kite downC . his friends do not know what to doD . he helps his friends get the kite down from the tree(5)From the passage (短文)we can see ____.A . Bill's friends help Bill make a new kiteB . Mr. Green cannot get the kite down but he doesn't want to make a new one for himC . Bill's father cannot get the kite down, so he makes a new one for BillD . Bill cannot get the kite down and his friends are very glad(6)How many children are there in Mr. Green's family?A . We don't know.B . Three.C . One.D . Two.(7)Bill likes to ___.A . play gamesB . make kitesC . fly kites onlyD . play other games and fly kites(8)One day ____.A . Bill makes a kite for his friendsB . Bill's friends mend his kiteC . Bill's kite is in the treeD . Bill finds a kite in a tree(9)Bill is glad because(因为) ____.A . Mr. Green makes a new kite for himB . his father helps him get the kite downC . his friends do not know what to doD . he helps his friends get the kite down from the tree(10)From the passage (短文)we can see ____.A . Bill's friends help Bill make a new kiteB . Mr. Green cannot get the kite down but he doesn't want to make a new one for himC . Bill's father cannot get the kite down, so he makes a new one for BillD . Bill cannot get the kite down and his friends are very glad18. (10分)If you go to Finland, you’ll be surprised to find how “foolish” the Finnish people are.Take the taxi drivers for example. Taxis in Finland are mostly high class Benz with a fare (票价) of two US dollars a kilometer. You can go anywhere in one, tell the driver to drop you at any place, say that you have some business to attend to, and then get off without paying your fare. And the driver would not show the least sign of worry.The dining rooms in all big hotels not only serve their guests, but also outside diners. Hotel guests have their meals free, so their good faith is to wave their registration card to the waiter. With such a loose check, you can easily use any old registration card to take a couple of friends and dine free of charge.With so many loopholes (漏洞) in everyday life, surely Finland must be a heaven to those who love to take “pretty advantages”. But the strange things is, all the taxi-passengers would always come back to pay their fare after they have attended to their business; not a single outsider has ever been found in the free hotel dining rooms. As the Finns always act on good faith and always show an attitude of “which is which” and “what is what” in everything they do, so to live in such a society has turned everyone into a real “gentleman”. In a society of such high moral practice, what need is there for people to take precautions (预防措施) against others?(1)The word “foolish” probably means _____________.A . friendlyB . carefulC . strangeD . funny(2)Why wouldn’t the d river show the least sign of worry? Because _________.A . he is sure that the passengers always act on good faithB . he is afraid to make the passengers angry and unhappyC . he thinks the passengers may be too poor to pay himD . he is sure that the passengers are really in trouble(3)The dining rooms in all big hotels ___________.A . check the guests’ registration card carefullyB . give people meals without payingC . serve their guests free of chargeD . only serve their guests free breakfast(4)What’s FALSE according to the passage?A . No one takes advantages although there are many loopholes.B . All the taxi-passengers come back to pay their fare after they have attended to their business.C . Not a single outsider has ever been found in the free hotel dining rooms.D . Finland is heaven for immoral people because they can always take advantages freely.(5)The sentences “which is which” and “what is what” show that __________.A . the Finns are foolishB . the Finns take things seriouslyC . the Finns are busy making money for the familyD . the Finns never take precaution against others19. (10分) Once I thought love meant flowers, gifts and sweet kisses (吻). So, I really doubt (怀疑) whether (是否) there is love between my parents. Every day they are very busy trying to make money to pay the schooling for me. They don't act in the romantic ways that I read in books or I see on TV, and sending flowers to each other on Valentine's Day is even impossible.One day, my mother was sewing a quilt (被子). I asked her if there was love between them. She stopped her work and looked up with surprise. Then she bowed (弯下) her head and continued sewing the quilt.I was very worried because I thought I hurt her. But after a few minutes she said, “Look at this thread (线). Sometimes it appears, but most of the time it disappears in the quilt. If life is a quilt, then love should be a thread. It can hardly (几乎不) be seen anywhere or anytime, but it’s really there, and makes the quilt long-lasting.” I listened carefully but I couldn't understand her until the next spring.My mother suddenly got sick seriously and had to stay in the hospital for a one-month treatment. Every morning and dusk (黄昏) after she returned from the hospital, my father helped my mother walk slowly on the country road. There were many beautiful flowers, green grass and trees, and the sun gently shone them through the leaves. All of these made up the most beautiful picture in the world. Reading their eyes, I knew they loved each other deeply. From this experience, I realized that love was just a thread in the quilt of our life. Love is inside, making life strong and warm.(1)The writer thought his parents' life was not .A . romanticB . greatC . meaningfulD . true(2)Valentine's Day may be a day for .A . parentsB . loversC . classmatesD . friends(3)What do the sentences in the third paragraph show?A . There is beautiful scenery (风景) everywhere in the world.B . There is true life anywhere in the world.C . There is no love without beautiful flowers.D . There is really love between the writer’s parents.(4)What is the best title of this passage?A . Love should appear every day.B . Love means flowers.C . Love is just the thread of a quiltD . True love.(5)The writer did not understand their parents' love until________.A . the next summerB . his mother was deadC . his mother was seriously illD . he himself grew up四、任务型阅读 (共1题;共1分)20. (1分)阅读下面的短文,并根据短文后的要求答题。
上海版2019届九年级上学期英语期中考试试卷(I)卷
上海版2019届九年级上学期英语期中考试试卷(I)卷一、单项填空 (共15题;共30分)1. (2分)Michael Jackson had ______ gift for singing and he was called ______ King of Pop.A . /, theB . a, theC . the, theD . a, a2. (2分)It seems to me that Lucy and Lily ________ your classmates.A . isB . areC . hasD . have3. (2分)— Hello, I'm Gina.— ____________A . Hi, Gina. I'm Alan.B . Good morning!C . Yes, I'm.D . How are you?4. (2分)—How long can I _____ the Chinese workbook?—For three weeks.A . borrowB . keepC . to borrowD . to keep5. (2分)—What _______ you just now?—Don't worry. Nothing _______.A . has happens to; has happenedB . happened; happenedC . happened; has happenedD . happened to; has happened6. (2分)You need to brush your______ after_______.A . tooth; eatB . teeth; eatC . tooth; eatingD . teeth; eating7. (2分)-- Are all the titles of the articles ______ in the contents?--Yes, all ______.A . listed; includedB . listing; includesC . listed; includingD . being listed; being included8. (2分)一How do you like the piece of music Water by Tan Dun? 一Wonderful! It's the ____one I've ever listened to.A . betterB . bestC . worseD . worst9. (2分)—Linda, I will go to the zoo with my parents today.—Oh, great! ______.A . Excuse meB . You're welcomeC . Thank youD . Have a nice day10. (2分)—Would you like to come to dinner tomorrow evening?—____.A . Yes, it's true.B . You really doC . It's upstairs.D . Yes, I'd love to.11. (2分)The summer holiday is coming. We're going to have _______ holiday.A . a two-monthB . a two-monthsC . two monthsD . two-months12. (2分)I don't know .A . where does she liveB . where she lives inC . where she lives13. (2分)You ______ do something. You don't do it often.A . neverB . alwaysC . seldom14. (2分)I heard Mary _______ the piano at that time.A . playB . playedC . playingD . to play15. (2分)— Which country do you think will win the first prize of the ____FIFA World Cup?—You mean the football match will be held in __________?A . twenty-one; RussiaB . twenty-first; RussianC . twenty-first; RussiaD . twenty-one; Russian二、完形填空 (共1题;共1分)16. (1分) My father is 40. He is a good driver1a good father.My father likes2sports very much. Every morning, he3and runs in the People's Park. He also plays basketball. He is s o strong and healthy. He always says to me, “Sports can make us strong.” My father loves4and his favorite book is Car Fanatics. He likes cars5.He wants to have an6car. It is his dream.I hope I can buy one7him in the future.I am8only daughter, and my father loves me very much. He buys me anything I want. When I make mistakes( 犯错误), he never hits(打)me. He says to me9a smile, “ 10do that again,” We love each other very much. I hope my father can keep healthy forever.(1)A . andB . orC . butD . so(2)A . doB . doesC . doingD . did(3)A . get upB . go to bedC . gets upD . goes to bed(4)A . readB . readsC . not to readD . reading(5)A . lotB . a lotC . lots ofD . a lot(6)A . JapaneseB . ChineseC . AmericanD . British(7)A . forB . toC . withD . on(8)A . herB . hisC . sheD . he(9)A . onB . withC . carryingD . after(10)A . Isn'tB . Doesn'tC . Don'tD . can't三、阅读理解 (共3题;共30分)17. (10分)A . He gets up too earlyB . He is a helpful person.C . He should see a doctorD . He makes too much noise(2)What does this way mean?A . Singing to a crying baby.B . Singing when taking a cold bath.C . Taking a cold bath in the morning.D . Taking a bath before going to bed.18. (10分)根据短文理解,选择正确答案。
2019-2020学年上海市浦东新区新竹园中学九年级(上)月考数学试卷试题及答案(9月份)
2019-2020学年上海市浦东新区新竹园中学九年级(上)月考数学试卷(9月份)一、选择题1.(3分)利用投影仪把Rt ABC ∆各边的长度都扩大5倍,则锐角A 的各三角函数值()A .都扩大5倍B .都缩小5倍C .没有变化D .不能确定2.(3分)在ABC ∆,点D 、E 分别在边AB 、AC 上,如果1AD =,2BD =,那么由下列条件能够判定//DE BC 的是()A .12DE BC =B .13DE BC =C .12AE AC =D .13AE AC =3.(3分)如图,正方形ABCD 中,E ,F 分别在边AD ,CD 上,AF ,BE 相交于点G ,若3AE ED =,DF CF =,则AGGF的值是()A .43B .54C .65D .764.(3分)如图,一块矩形木板ABCD 斜靠在墙边(OC OB ⊥,点A ,B ,C ,D ,O 在同一平面内),已知AB a =,AD b =,BCO x ∠=,则点A 到OC 的距离等于()A .sin sin a x b x +B .cos cos a x b x +C .sin cos a x b x +D .cos sin a x b x+5.在Rt ABC ∆中,90C ∠=︒,CD 是高,如果AD m =,A α∠=,那么BC 的长为()A .tan cos m ααB .cot cos m ααC .tan cos m ααD .tan sin m αα6.(3分)如图,已知ABC ∆和DEF ∆,点E 在BC 边上,点A 在DE 边上,边EF 和边AC 相交于点G .如果AE EC =,AEG B ∠=∠,那么添加下列一个条件后,仍无法判定DEF ∆与ABC ∆一定相似的是()A .AB DEBC EF=B .AD GFAE GE=C .AG EGAC EF=D .ED EGEF EA=二、填空题7.(3分)已知点P 是线段AB 的一点,且BP 是AB 和AP 的比例中项,若2AB cm =,则线段AP =cm .8.(3分)如果二次函数22(1)51y m x x m =-++-的图象经过原点,那么m =.9.(3分)如果将抛物线23y x =平移,使平移后的抛物线顶点坐标为(2,2),那么平移后的抛物线的表达式为.10.(3分)已知抛物线2y x bx c =++经过点(0,5)A 、(4,5)B ,那么此抛物线的对称轴是.11.(3分)某飞机的飞行高度为1500m ,从飞机上测得地面控制点的俯角为60︒,此时飞机与这地面控制点的距离为m .12.(3分)如图,在平行四边形ABCD 中,点E 在边DC 上,:3:1DE EC =,连接AE 交BD 于点F ,则DEF ∆的面积与DAB ∆的面积之比为.13.(3分)如图,在由10个完全相同的正三角形构成的网格图中,α∠、β∠如图所示,则cos()αβ+=.14.(3分)已知:如图,在梯形ABCD 中,//AB CD ,3AB CD =,如果,AB a AD b == ,那么AC =(用向量,a b 的式子表示).15.(3分)如图,把n 个边长为1的正方形拼接成一排,求得1tan 1BA C ∠=,21tan 3BA C ∠=,31tan 7BA C ∠=,计算4tan BA C ∠=,⋯按此规律,写出tan n BA C ∠=(用含n 的代数式表示).16.(3分)在平面直角坐标系中,抛物线2y x =的图象如图所示.已知A 点坐标为(1,1),过点A 作1//AA x 轴交抛物线于点1A ,过点1A 作12//A A OA 交抛物线于点2A ,过点2A 作23//A A x 轴交抛物线于点3A ,过点3A 作34//A A OA 交抛物线于点4A ⋯⋯,依次进行下去,则点2019A 的坐标为.17.(3分)如果三角形有一边上的高恰好等于这边长的12,那么称这个三角形为“好玩三角形”,在Rt ABC ∆是“好玩三角形”,且90C ∠=︒,则tan A =.18.(3分)如图,等边ABC ∆的边长为10,点M 是边AB 上一动点,将等边ABC ∆沿过点M 的直线折叠,该直线与直线AC 交于点N ,使点A 落在直线BC 上的点D 处,且:1:4BD DC =,折痕为MN ,则AN 的长为.三、解答题19.计算:2tan 602cos 45tan 45cot 45cos30︒︒+-︒︒+︒.20.《九章算术》是我国古代数学名著,书中有下列问题:“今有勾五步,股十二步,问勾中容方几何?”其意思为:“今有直角三角形,勾(短直角边)长为5步,股(长直角边)长为12步,问该直角三角形能容纳的正方形边长最大是多少步?”21.在ABC ∆中,90ABC ∠=︒,如图1,分别过A 、C 两点作经过点B 的直线的垂线,垂足分别为M 、N ,则~ABM BCN ∆∆;(1)如图2,P 是边BC 上一点,BAP C ∠=∠,tan PAC ∠=tan C 的值;(2)如图3,D 是边CA 延长线上一点,AE AB =,90DEB ∠=︒,3sin 5BAC ∠=,25AD AC =,直接写出tan CEB ∠的值.22.如图1为放置在水平桌面l 上的台灯,底座的高AB 为5cm ,长度均为20cm 的连杆BC ,CD 与AB 始终在同一平面上.(1)转动连杆BC ,CD ,使BCD ∠成平角,150ABC ∠=︒,如图2,求连杆端点D 离桌面l 的高度DE .(2)将(1)中的连杆CD 再绕点C 逆时针旋转,使165BCD ∠=︒,如图3,问此时连杆端点D 离桌面l 的高度是增加还是减少?增加或减少了多少?(精确到0.1cm ,参考数据:2 1.41≈,3 1.73)≈23.如图1,点P 为MON ∠的平分线上一点,以P 点为顶点的角的两边分别与射线OM ,ON 交于A ,B 两点,如果APB ∠绕点P 旋转时始终满足2OA OB OP = ,我们就把APB ∠叫做MON ∠的智慧角.(1)如图2,已知90MON ∠=︒,点P 为MON ∠的平分线上一点,以点P 为顶点的角的两边分别与射线OM ,ON 交于A ,B 两点,且135APB ∠=︒,求证:APB ∠是MON ∠的智慧角;(2)如图1,已知MON α∠=,(090)α︒<<︒,2OP =,若APB ∠是MON ∠的智慧角,连结AB ,用含α的式子分别表示APB ∠的度数和AOB ∆的面积.24.下表中给出了变量x 与2ax ,2ax bx c ++之间的部分对应值(表格中的符号“⋯”表示该项数据已经丢失)x1-012ax ⋯⋯12ax bx c++72⋯(1)写出这条抛物线的开口方向,顶点D 的坐标;并说明它的变化情况;(2)抛物线2y ax bx c =++的顶点为D ,与y 轴的交点为A ,点M 是抛物线对称轴上的一点,直线AM 交对称轴右侧的抛物线于点B ,当ADM ∆与BDM ∆的面积比为2:3时,求点B 的坐标;(3)在(2)的条件下,设线段BD 交x 轴于点C ,试写出BAD ∠与DCO ∠的数量关系,并说明理由.25.如图,梯形ABCD 中,//AD BC ,DC BC ⊥,且45B ∠=︒,1AD DC ==,点M 为边BC 上一动点,联结AM 并延长交射线DC 于点F ,作45FAE ∠=︒交射线BC 于点E 、交边DCN 于点N ,联结EF .(1)当:1:4CM CB =时,求CF 的长.(2)设CM x =,CE y =,求y 关于x 的函数关系式,并写出定义域.(3)当ABM EFN ∆∆∽时,求CM 的长.2019-2020学年上海市浦东新区新竹园中学九年级(上)月考数学试卷(9月份)参考答案与试题解析一、选择题1.(3分)利用投影仪把Rt ABC ∆各边的长度都扩大5倍,则锐角A 的各三角函数值()A .都扩大5倍B .都缩小5倍C .没有变化D .不能确定【解答】解: 各边的长度都扩大五倍,∴扩大后的三角形与Rt ABC ∆相似,∴锐角A 的各三角函数值都不变.故选:C .2.(3分)在ABC ∆,点D 、E 分别在边AB 、AC 上,如果1AD =,2BD =,那么由下列条件能够判定//DE BC 的是()A .12DE BC =B .13DE BC =C .12AE AC =D .13AE AC =【解答】解:1AD = ,2BD =,∴13AD AB =,只有当13AE AC =时,//DE BC ,理由是:13AD AE AB AC ==,A A ∠=∠,ADE ABC ∴∆≅∆,ADE B ∴∠=∠,//DE BC ∴,而其它选项都不能推出ADE ABC ∆∆∽,即不能推出ADE B ∠=∠或AED C ∠=∠,即不能推出//DE BC ,即选项A 、B 、C 都错误,只有选项D 正确;故选:D .3.(3分)如图,正方形ABCD 中,E ,F 分别在边AD ,CD 上,AF ,BE 相交于点G ,若3AE ED =,DF CF =,则AGGF的值是()A .43B .54C .65D .76【解答】解:如图作,//FN AD ,交AB于N ,交BE 于M .四边形ABCD 是正方形,//AB CD ∴,//FN AD ,∴四边形ANFD 是平行四边形,90D ∠=︒ ,∴四边形ANFD 是矩形,3AE DE = ,设DE a =,则3AE a =,4AD AB CD FN a ====,2AN DF a ==,AN BN = ,//MN AE ,BM ME ∴=,32MN a ∴=,52FM a ∴=,//AE FM ,∴36552AG AE a GF FM a ===,故选:C .4.(3分)如图,一块矩形木板ABCD 斜靠在墙边(OC OB ⊥,点A ,B ,C ,D ,O 在同一平面内),已知AB a =,AD b =,BCO x ∠=,则点A 到OC 的距离等于()A .sin sin a x b x +B .cos cos a x b x +C .sin cos a x b x +D .cos sin a x b x+【解答】解:作AE OC ⊥于点E ,作AF OB ⊥于点F , 四边形ABCD 是矩形,90ABC ∴∠=︒,ABC AEC ∠=∠ ,BCO x ∠=,EAB x ∴∠=,FBA x ∴∠=,AB a = ,AD b =,cos sin FO FB BO a x b x ∴=+=+ ,故选:D .5.在Rt ABC ∆中,90C ∠=︒,CD 是高,如果AD m =,A α∠=,那么BC 的长为()A .tan cos m ααB .cot cos m ααC .tan cos m ααD .tan sin m αα【解答】解: 在Rt ABC ∆中,90C ∠=︒,CD 是高,如果AD m =,A α∠=,tan CD CDAD mα∴==,tan CD m α∴= ,90ACB A B ∠=∠+∠=︒ ,90BDC B BCD ∠=∠+∠=︒,A α∠=,BCD α∴∠=,tan cos CD m BCD BC BCα∴∠==,即tan cos m BCαα= ,tan cos m BC αα=.故选:C .6.(3分)如图,已知ABC ∆和DEF ∆,点E 在BC 边上,点A 在DE 边上,边EF 和边AC 相交于点G .如果AE EC =,AEG B ∠=∠,那么添加下列一个条件后,仍无法判定DEF ∆与ABC ∆一定相似的是()A .AB DE BC EF =B .AD GF AE GE =C .AG EG AC EF =D .ED EGEF EA=【解答】解:当AB DE BC EF =时,则AB BCDE EF=,而B AEG ∠=∠,所以ABC EDF ∆∆∽;当AD GF AE GE =,则DE EF AE EG=,而DEF AEG ∠=∠,所以DEF AEG ∆∆∽,又因为AE EC =,所以EAG C ∠=∠,而AEG B ∠=∠,所以AEG ABC ∆∆∽,所以ABC EDF ∆∆∽;当ED EG EF EA =,则DE EFAE EG=,而DEF AEG ∠=∠,所以DEF AEG ∆∆∽,又因为AE EC =,所以EAG C ∠=∠,而AEG B ∠=∠,所以AEG ABC ∆∆∽,所以ABC EDF ∆∆∽.故选:C .二、填空题7.(3分)已知点P 是线段AB 的一点,且BP 是AB 和AP 的比例中项,若2AB cm =,则线段AP =(35)-cm .【解答】解:根据题意得2BP AB AP = ,设AP x =,则2BP x =-,所以2(2)2x x -=,整理得2640x x -+=,解得135x =,235x =-,即线段AP 的长度为(3cm -.故答案为(3-.8.(3分)如果二次函数22(1)51y m x x m =-++-的图象经过原点,那么m =1-.【解答】解: 二次函数22(1)51y m x x m =-++-的图象经过原点,210m ∴-=,解得1m =±,函数为二次函数,10m ∴-≠,解得1m ≠,所以,1m =-.故答案为:1-.9.(3分)如果将抛物线23y x =平移,使平移后的抛物线顶点坐标为(2,2),那么平移后的抛物线的表达式为23(2)2y x =-+.【解答】解: 原抛物线解析式为23y x =,的顶点坐标是(0,0),平移后抛物线顶点坐标为(2,2),∴平移后的抛物线的表达式为:23(2)2y x =-+.故答案为:23(2)2y x =-+.10.(3分)已知抛物线2y x bx c =++经过点(0,5)A 、(4,5)B ,那么此抛物线的对称轴是直线2x =.【解答】解: 点(0,5)A 、(4,5)B 的纵坐标都是5相同,∴抛物线的对称轴为直线0422x +==.故答案为:直线2x =.11.(3分)某飞机的飞行高度为1500m ,从飞机上测得地面控制点的俯角为60︒,此时飞机与这地面控制点的距离为.【解答】解:设此时飞机与地面控制点的距离为x 米.1500sin 60x︒=,x =故答案为:12.(3分)如图,在平行四边形ABCD 中,点E 在边DC 上,:3:1DE EC =,连接AE 交BD 于点F ,则DEF ∆的面积与DAB ∆的面积之比为9:28.【解答】解: 四边形ABCD 为平行四边形,//DC AB ∴,DFE BFA ∴∆∆∽,:3:1DE EC = ,:3:4DE DC ∴=,:3:4DE AB ∴=,:9:16DFE BFA S S ∆∆∴=,:::4:316:12ABF ADF S S BF DF AB DE ∆∆==== ,:9:28DEF DAB S S ∆∆∴=故答案为:9:28.13.(3分)如图,在由10个完全相同的正三角形构成的网格图中,α∠、β∠如图所示,则cos()αβ+=7.【解答】解:给图中相关点标上字母,连接DE ,如图所示.在ABC ∆中,120ABC ∠=︒,BA BC =,30α∴∠=︒.同理,可得出:30CDE CED α∠=∠=︒=∠.又60AEC ∠=︒ ,90AED AEC CED ∴∠=∠+∠=︒.设等边三角形的边长为a ,则2AE a =,2sin 60DE a =⨯︒= ,AD ∴==,cos()7DE AD αβ∴+==.故答案为:7.14.(3分)已知:如图,在梯形ABCD 中,//AB CD ,3AB CD =,如果,AB a AD b == ,那么AC = 13a b -+ (用向量a b 的式子表示).【解答】解:如图,//AB CD ,3AB CD =,AB a = ,∴1133DC AB a =-=- .又 AD b = ,∴13AC AD DC a b =+=-+ .故答案是:13a b -+ .15.(3分)如图,把n 个边长为1的正方形拼接成一排,求得1tan 1BA C ∠=,21tan 3BA C ∠=,31tan 7BA C ∠=,计算4tan BA C ∠=113,⋯按此规律,写出tan n BA C ∠=(用含n 的代数式表示).【解答】解:作4CH BA ⊥于H ,由勾股定理得,4BA ==,4A C =△4BA C 的面积314222=--=,∴1122CH =,解得,17CH =,则417A H ==,441tan 13CH BA C A H ∴∠==,21111=-+,23221=-+,27331=-+,21tan 1n BA C n n ∴∠=-+,故答案为:113;211n n -+.16.(3分)在平面直角坐标系中,抛物线2y x =的图象如图所示.已知A 点坐标为(1,1),过点A 作1//AA x 轴交抛物线于点1A ,过点1A 作12//A A OA 交抛物线于点2A ,过点2A 作23//A A x 轴交抛物线于点3A ,过点3A 作34//A A OA 交抛物线于点4A ⋯⋯,依次进行下去,则点2019A 的坐标为(1010-,21010).【解答】解:A 点坐标为(1,1),∴直线OA 为y x =,1(1,1)A -,12//A A OA ,∴直线12A A 为2y x =+,解22y x y x =+⎧⎨=⎩得11x y =-⎧⎨=⎩或24x y =⎧⎨=⎩,2(2,4)A ∴,3(2,4)A ∴-,34//A A OA ,∴直线34A A 为6y x =+,解26y x y x =+⎧⎨=⎩得24x y =-⎧⎨=⎩或39x y =⎧⎨=⎩,4(3,9)A ∴,5(3,9)A ∴-⋯,2019(1010A ∴-,21010),故答案为(1010-,21010).17.(3分)如果三角形有一边上的高恰好等于这边长的12,那么称这个三角形为“好玩三角形”,在Rt ABC ∆是“好玩三角形”,且90C ∠=︒,则tan A =12或2或1.【解答】解:分三种情况:①如图1,高12AC BC =,此时tan 212BC BC A AC BC ===;②如图2,高12BC AC =,此时112tan 2AC BC A AC AC ===;③如图3,高12CD AB =,设AC x =,BC y =,CD a =,则2AB a =,由三角形面积公式和勾股定理得:2222(2)a a xy x y a =⎧⎨+=⎩,解得:x y =(负数舍去),tan 1BC A AC==;故答案为:12或2或1.18.(3分)如图,等边ABC ∆的边长为10,点M 是边AB 上一动点,将等边ABC ∆沿过点M 的直线折叠,该直线与直线AC 交于点N ,使点A 落在直线BC 上的点D 处,且:1:4BD DC =,折痕为MN ,则AN 的长为7或653.【解答】解:①当点A 落在如图1所示的位置时,ACB ∆ 是等边三角形,60A B C MDN ∴∠=∠=∠=∠=︒,MDC B BMD ∠=∠+∠ ,B MDN ∠=∠,BMD NDC ∴∠=∠,BMD CDN ∴∆∆∽.∴得BD DM BM CN DN CD==,DN AN = ,∴得BD DN BM CN AN CD ==,:1:4BD DC = ,10BC =,2DB ∴=,8CD =,设AN x =,则10CN x =-,∴2108DM BM x x ==-,210x DM x ∴=-,1610BM x =-,10BM DM += ,∴216101010x x x+=--,解得7x =,7AN ∴=;②当A 在CB 的延长线上时,如图2,与①同理可得BMD CDN ∆∆∽.∴得BD DM BM CN DN CD==,:1:4BD DC = ,10BC =,103DB ∴=,403CD =,设AN x =,则10CN x =-,∴10340103DM BM x x ==-,103(10)x DM x ∴=-,4009(10)BM x =-,10BM DM += ,∴10400103(10)9(10)x x x +=--,解得:653x =,653AN ∴=.故答案为:7或653.三、解答题19.计算:2tan 602cos 45tan 45cot 45cos30︒︒+-︒︒+︒.【解答】解:原式222()122=⨯+1212=⨯+11=+6=.20.《九章算术》是我国古代数学名著,书中有下列问题:“今有勾五步,股十二步,问勾中容方几何?”其意思为:“今有直角三角形,勾(短直角边)长为5步,股(长直角边)长为12步,问该直角三角形能容纳的正方形边长最大是多少步?”【解答】解:如图1, 四边形CDEF 是正方形,CD ED ∴=,//DE CF ,设ED x =,则CD x =,12AD x =-,//DE CF ,ADE C ∴∠=∠,AED B ∠=∠,ADE ACB ∴∆∆∽,∴DE AD BC AC =,∴12512x x -=,6017x =,如图2,四边形DGFE 是正方形,过C 作CP AB ⊥于P ,交DG 于Q ,设ED x =,1122S ABC AC BC AB CP ∆== ,12513CP ⨯=,6013CP =,同理得:CDG CAB ∆∆∽,∴DG CQ AB CP=,∴6013601313x x -=,7806022917x =<,∴该直角三角形能容纳的正方形边长最大是6017(步).21.在ABC ∆中,90ABC ∠=︒,如图1,分别过A 、C 两点作经过点B 的直线的垂线,垂足分别为M 、N ,则~ABM BCN ∆∆;(1)如图2,P 是边BC 上一点,BAP C ∠=∠,tan 5PAC ∠=,求tan C 的值;(2)如图3,D 是边CA 延长线上一点,AE AB =,90DEB ∠=︒,3sin 5BAC ∠=,25AD AC =,直接写出tan CEB ∠的值.【解答】解:(1)AM MN ⊥ ,CN MN ⊥,90AMB BNC ∴∠=∠=︒,90BAM ABM ∴∠+∠=︒,90ABC ∠=︒ ,90ABM CBN ∴∠+∠=︒,BAM CBN ∴∠=∠,AMB NBC ∠=∠ ,ABM BCN ∴∆∆∽;(2)如图2,过点P 作PM AP ⊥交AC 于M ,PN AM ⊥于N .1190BAP CPM ∴∠+∠=∠+∠=︒,BAP CPM C ∴∠=∠=∠,MP MC∴=tan5PN MN PAC AN PN ∠==== ,设2MN m =,PN =,根据勾股定理得,3PM m CM ===,tan PN C CN ∴==(3)在Rt ABC ∆中,3sin 5BC BAC AC ∠==,过点A 作AG BE ⊥于G ,过点C 作CH BE ⊥交EB 的延长线于H ,90DEB ∠=︒ ,////CH AG DE ∴,∴52GH EG =同(1)的方法得,ABG BCH ∆∆∽∴43BG AG AB CH BH BC ===,设4BG m =,3CH m =,4AG n =,3BH n =,AB AE = ,AG BE ⊥,4EG BG m ∴==,43GH BG BH m n ∴=+=+,∴43542m n m +=,2n m ∴=,443838614EH EG GH m m n m n m m m ∴=+=++=+=+=,在Rt CEH ∆中,3tan 14CH BEC EH ∠==.22.如图1为放置在水平桌面l上的台灯,底座的高AB为5cm,长度均为20cm的连杆BC,CD与AB始终在同一平面上.(1)转动连杆BC,CD,使BCD∠=︒,如图2,求连杆端点D离桌面ABC∠成平角,150l的高度DE.(2)将(1)中的连杆CD再绕点C逆时针旋转,使165BCD∠=︒,如图3,问此时连杆端点D离桌面l的高度是增加还是减少?增加或减少了多少?(精确到0.1cm,参考数据:≈≈,3 1.73)2 1.41【解答】解:(1)如图2中,作BO DE⊥于O.,∠=∠=∠=︒OEA BOE BAE90∴四边形ABOE是矩形,∴∠=︒,OBA90∴∠=︒-︒=︒,1509060DBOsin 60)OD BD cm ∴=︒= ,539.6()DF OD OE OD AB cm ∴=+=+=≈.(2)作DF l ⊥于F ,CP DF ⊥于P ,BG DF ⊥于G ,CH BG ⊥于H .则四边形PCHG 是矩形,60CBH ∠=︒ ,90CHB ∠=︒,30BCH ∴∠=︒,165BCD ∠=︒ ,45DCP ︒∠=︒,sin 60)CH BC cm ∴=︒=,sin 45)DP CD cm =︒=,5)()DF DP PG GF DP CH AB cm ∴=++=++=,∴下降高度:55 3.2()DE DF cm -=-=.23.如图1,点P 为MON ∠的平分线上一点,以P 点为顶点的角的两边分别与射线OM ,ON 交于A ,B 两点,如果APB ∠绕点P 旋转时始终满足2OA OB OP = ,我们就把APB ∠叫做MON ∠的智慧角.(1)如图2,已知90MON ∠=︒,点P 为MON ∠的平分线上一点,以点P 为顶点的角的两边分别与射线OM ,ON 交于A ,B 两点,且135APB ∠=︒,求证:APB ∠是MON ∠的智慧角;(2)如图1,已知MON α∠=,(090)α︒<<︒,2OP =,若APB ∠是MON ∠的智慧角,连结AB ,用含α的式子分别表示APB ∠的度数和AOB ∆的面积.【解答】(1)证明:90MON ∠=︒ ,P 为MON ∠的平分线上一点,1452AOP BOP MON ∴∠=∠=∠=︒,180AOP OAP APO ∠+∠+∠=︒ ,135OAP APO ∴∠+∠=︒,135APB ∠=︒ ,135APO OPB ∴∠+∠=︒,OAP OPB ∴∠=∠,AOP POB ∴∆∆∽,∴OA OP OP OB=,2OP OA OB ∴= ,APB ∴∠是MON ∠的智慧角;(2)解:APB ∠ 是MON ∠的智慧角,2OA OB OP ∴= ,∴OA OP OP OB=,P 为MON ∠的平分线上一点,12AOP BOP α∴∠=∠=,AOP POB ∴∆∆∽,OAP OPB ∴∠=∠,11802APB OPB OPA OAP OPA α∴∠=∠+∠=∠+∠=︒-,即11802APB α∠=︒-;过点A 作AH OB ⊥于H ,连接AB ;如图1所示:则2111sin sin 222AOB S OB AH OB OA OP αα∆=== ,2OP = ,2sin AOB S α∆∴=.24.下表中给出了变量x 与2ax ,2ax bx c ++之间的部分对应值(表格中的符号“⋯”表示该项数据已经丢失)x 1-012ax ⋯⋯12ax bx c ++72⋯(1)写出这条抛物线的开口方向,顶点D 的坐标;并说明它的变化情况;(2)抛物线2y ax bx c =++的顶点为D ,与y 轴的交点为A ,点M 是抛物线对称轴上的一点,直线AM 交对称轴右侧的抛物线于点B ,当ADM ∆与BDM ∆的面积比为2:3时,求点B 的坐标;(3)在(2)的条件下,设线段BD 交x 轴于点C ,试写出BAD ∠与DCO ∠的数量关系,并说明理由.【解答】解:(1)当1x =时,21y ax ==,解得:1a =;将(1,7)-、(0,2)代入2y x bx c =++,得:172b c c -+=⎧⎨=⎩,解得:42b c =-⎧⎨=⎩,∴抛物线的表达式为242y x x =-+或2(2)2y x =-+,∴该抛物线的开口向上,(2,2)D -;(2)ADM ∆ 和BDM ∆同底,且ADM ∆与BDM ∆的面积比为2:3,∴点A 到抛物线的距离与点B 到抛物线的距离比为2:3.抛物线2(2)2y x =-+的对称轴为直线2x =,点A 的横坐标为0,∴点B 到抛物线的距离为3,∴点B 的横坐标为325+=,∴点B 的坐标为(5,7).(3)BAD ∠和DCO ∠互补,理由如下:当0x =时,2422y x x =-+=,∴点A 的坐标为(0,2),2242(2)2y x x x =-+=-- ,∴点D 的坐标为(2,2)-.过点A 作//AN x 轴,交BD 于点N ,则AND DCO ∠=∠,如图所示.设直线BD 的表达式为(0)y mx n m =+≠,将(5,7)B 、(2,2)D -代入y mx n =+,5722m n m n +=⎧⎨+=-⎩,解得:38m n =⎧⎨=-⎩,∴直线BD 的表达式为38y x =-.当2y =时,有382x -=,解得:103x =,∴点N 的坐标为10(3,2).(0,2)A ,(5,7)B ,(2,2)D -,AB ∴=,BD =,BN =∴BNBABA BD ==.又ABD NBA ∠=∠ ,ABD NBA ∴∆∆∽,ANB DAB ∴∠=∠.180ANB AND ∠+∠=︒ ,180DAB DCO ∴∠+∠=︒,BAD ∴∠和DCO ∠互补.25.如图,梯形ABCD 中,//AD BC ,DC BC ⊥,且45B ∠=︒,1AD DC ==,点M 为边BC 上一动点,联结AM 并延长交射线DC 于点F ,作45FAE ∠=︒交射线BC 于点E 、交边DCN 于点N ,联结EF .(1)当:1:4CM CB =时,求CF 的长.(2)设CM x =,CE y =,求y 关于x 的函数关系式,并写出定义域.(3)当ABM EFN ∆∆∽时,求CM 的长.【解答】解:(1)如图1中,作AH BC ⊥于H .CD BC ⊥ ,//AD BC ,90BCD D AHC ∴∠=∠=∠=︒,∴四边形AHCD 是矩形,1AD DC == ,∴四边形AHCD 是正方形,1AH CH CD ∴===,45B ∠=︒ ,1AH BH ∴==,2BC =,1142CM BC == ,//CM AD ,∴CM CF AD DF=,∴1211CF CF =+,1CF ∴=.(2)如图1中,在Rt AEH ∆中,222221(1)AE AH EH y =+=++,AEM AEB ∠=∠ ,EAM B ∠=∠,EAM EBA ∴∆∆∽,∴AE EM EB EA=,2AE EM EB ∴= ,21(1)()(2)y x y y ∴++=++,22x y x-∴=,220x -> ,01x ∴< .(3)如图2中,作AH BC ⊥于H ,连接MN ,在HB 上取一点G ,使得HG DN =,连接AG.则ADN AHG ∆≅∆,MAN MAG ∆≅∆,MN MG HM GH HM DN ∴==+=+,ABM EFN ∆∆ ∽,45EFN B ∴∠=∠=︒,CF CE ∴=,四边形AHCD 是正方形,CH CD AH AD ∴===,EH DF =,90AHE D ∠=∠=︒,AHE ADF ∴∆≅∆,AEH AFD ∴∠=∠,AEH DAN ∠=∠ ,AFD HAM ∠=∠,HAM DAN ∴∠=∠,ADN AHM ∴∆≅∆,DN HM ∴=,设DN HM x ==,则2MN x =,CN CM ==,1x ∴=,1x ∴=,2CM ∴=-。
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上海民办新竹园中学2019学年第一学期九年级考3物理学科考试卷(考试时间60分钟满分90分命题人陈晓东老师)一、选择题(每题2分,共16分)1.一本九年级上册物理书平放在桌面上对桌面的压强大约是()A.5帕B.15帕C.30帕D.100帕2.下列物理量中,以科学家焦耳的名字作单位的是()A.电功率B.电功C.电压D.电流3.家庭常用节能灯正常工作电流约为()A. 1安B.10安C. 0.05安D. 0.5安4. 物理知识在生活中有很多应用,下列用品中利用大气压原理工作的是()A.高压锅煮饭B.吸管喝饮料C.注射器注射药液D. 酒水壶酒水5. 如图所示的四个电路中,电源电压都相同且不变,电阻R的阻值均相等。
闭合开关S后,电流表示数最大的是()A.B.C.D.6.如图所示,取4个完全相同的正方体物块,分别以甲、乙、丙三种方式叠放(均放在中央位置),在三种叠放方式中,其中底层物块上表面受到的压强分别为p甲、p乙、p丙,则p甲:p乙:p丙关系为()A.3:1:3B.3:2:3C.3:3:4D.2:1:27.如图所示的电路中,电源电压保持不变。
在电路中并联一个电压表,当滑动变阻器R1的滑片P从a端移至c端,电压表的示数从零变为6伏,则下列判断正确的是()A.电压表并联在R1两端,滑片P位于中点b时电压表的示数为3伏B.电压表并联在R1两端,滑片P位于中点b时电压表的示数大于3伏C.电压表并联在R1两端,滑片P位于中点b时电压表的示数小于3伏D.电压表并联在R2两端,滑片P位于中点b时电压表的示数为3伏8.均匀正方体甲和乙放置在水平地面上。
已知甲密度小于乙的密度,且甲、乙对水平地面的压强相等。
现分别在甲、乙上沿水平方向截去一定体积,剩余部分对水平地面的压强仍然相等,截去部分的质量分别为△m甲、△m乙,截去部分的体积分别为△V甲、△V乙,则下列说法正确的是()A.△m甲一定小于△m乙B.△V甲可能小于△V乙C.△m甲可能等于△m乙D.△V甲一定大于△V乙二、填空题(每空1分,20、21、22、23 空每空2分,共27分)9.导体两端的电压是导体中自由电荷做移动的原因. 物理学规定电流是从电源的极流出的. 马路上的路灯之间是连接的(选填“串联”或“并联”)。
10.某电灯标有“220V 40W”的字样,将它接在伏的电路中时能正常工作,“40W”表示它的为40W: 该灯连续正常工作10小时,消耗电能度。
11. 实验第一次证明了大气压的存在,实验表明大气压强的大小随海拔高度的变化而变化,海拔高度越低,大气压强就越选填(“大”或“小”),热气球上常用的高度计实际上是将(填写仪器名称)经重新标度后直接显示海拔高度的。
12.某小球质量为3kg,体积为4X10-3米3。
将小球投放入水中后静止时时受到的浮力大小,方向竖直向,小球的重力为牛,小球在水中处于状态(选填“漂浮”、“悬浮”或沉底”)13.小明在研究串联电路的电流特点时,发现灯L1比灯L2亮,便作出“通过L1的电流大于通过L2的电流”的假设,由此推理,在图中A、B、C三点的电流I A、I B、I C大小关系为。
基于以上假设,若在A点串联一个电流表,闭合电键后,电流表示数(选填“能”或“不能”)看作通过L1后的电流。
若通过实验测量后,比较I A、I B、I C发现,则说明小明的假设是错误的。
14.在如图所示电路中,若在电路中串联一只电流表,当滑片P向b点移动时,电流表示数会(选填“变大”“不变”或“变小”)在电路中再并联一只电压表,当滑片P移动时,电压表示数与电流表示数的比值不发生变化,则电压表并联在(选填“R1”“R2”或“电源”)两端;电压表示数与电流表示数的比值发生变化,则电压表并联在(选填“R1”“R2”或“电源”)两端。
15.在图所示的电路中,电源电压保持不变。
电键S闭合后,电压表V无示数,已知电阻R1、R2中仅有一个出现了故障。
△现用一个完好的灯泡去替换电阻R2,则小灯(选填“一定发光”、“一定不发光”或“可能发光”)。
②若在电路中串联一个电流表,请写出各电表的示数及对应的故障。
16. 在课外实践活动中,某小组同学为了探究纸锥竖直下落时间长短与哪些因素有关。
他们用质量、形状不同的纸锥进行竖直下落实验,并用闪光照相机记录不同纸锥从同一高度下落的运动情况,照相机每隔0.2s曝光一次,拍摄的照片如图所示。
已知图(a)、(b)中,纸锥的质量相同,形状不同,(b)中纸锥的锥头更尖。
图8(b)、(c)中,纸锥的形状相同,质量不同,(c)中纸锥质量较大。
请根据实验现象及相关条件,归纳得出初步结论。
△分析比较图中的(a)与(b),可得到的初步结论是:;△分析比较图8中的(b)与(c),可得到的初步结论是:。
三、作图题(共5分)17.在图8中,重为2牛的小球漂浮在水面上,用力的图示法画出小球所受的浮力。
18.在图9所示的电路中,有两根导线尚未连接,请用笔线代替导线补上。
要求:闭合开关,将滑动变阻器的滑片向右移动,电流表示数变大,但灯L的亮暗程度不变。
图8 图9四、计算题(19、20题各4分,21题、22题各8分,共24分)19.体积为2×10-3m3的冰熔化成水后。
(ρ冰=0.9×103kg/m3)求:(1)冰的质量。
(2)熔化成水后的体积。
20.如图所示电路中电源电压保持不变,定值电阻R2阻值为10欧,闭合电键后,通过R2的电流为0.6安,干路中的电流为1安。
求:(1)电源电压U;(2)定值电阻R1消耗的电功率P1。
21.轻质薄壁圆柱形容器置于水平地面,容器中盛有0.2m深的水,(1)求容器底受到水的压强(2)现有质量为4千克的物体,其底面积是容器的一半。
若通过两种方法增大地面受到的压强,并测出压强的变化量,如下表所示。
方法地面受到压强的变化量(帕)将物体放入容器中980将物体垫在容器下方2940根据表中的信息:①通过计算求出原容器中水的质量;②计算判断将物体放入容器时是否有水溢出,若有水溢出请求出溢出水的重力G发水,若无水溢出,请说明理由。
22.在图所示的电路中,电阻R1的阻值为5欧,滑动变阻器上标有“20Ω 2Α”字样。
现有电压为6伏的电源一个,表盘如图(a)、(b)所示的电流表、电压表各一个。
△若在AB间接入电源,CD间接入电压表,闭合电键后,电压表示数为2伏,求通过电阻R1的电流I1和此时变阻器R2连入电路的阻值。
△请选择一个电表,将电源和选择的电表接入AB、CD间,要求移动变阻器的滑片P时通过变阻器的电流变化量△I最大。
(a)写出选择的电表及电表接入的位置。
(b)求出通过变阻器的电流变化量的最大值△I最大。
五、实验题(每空1分,共18分)23.如图所示的仪器名称为,当它浸入液体的体积越多,说明该液体的。
意大利科学家首先测出大气压强的值。
某地区的等高线如图所示,在该地区同一时刻,A位置的大气压B位置的大气压(选填“>”、“=”或“<”)24.在“测定物质的密度”实验中,需要测量的物理量是和。
在“探究物质质量与体积的关系”实验中,为了得出普遍规律,要多次测量不同体积同种物质的,并选择物质进行多次测量(选填“一种”或“多种”)。
25. 甲同学要测定导体R x的电阻,乙同学要测定标有“3.8V”字样小灯L的额定电功率。
他们选取了电压均为6伏的电源、均标有“20Ω 2A”字样的滑动变阻器及电键和导线等。
但在选取电表时,发现可选择的器材中只有一个电流表和一个电压表,经讨论后两位同学各选取了一个电表。
接着,他们分别将所选电表正确接入电路,并按规范步骤进行操作。
(1)为了能顺利完成各自的测量任务,选取电压表的是同学。
两位同学实验依据的原理(选填“相同”或“不同”).连接电路时,电键应处于状态。
(2)选取电流表的同学闭合电键时,电流表示数0.16安;移动变阻器滑片至中点位置时(即它接入电路的电阻10欧),电流表示数0.22安。
选取电压表的同学闭合电键时,将滑片移至中点位置时,小灯泡正常发光,电压表示数2.2伏。
综合上述信息,甲同学测得R x的电阻是欧,乙同学测得小灯L的额定电功率是瓦。
并画出乙同学实验电路图。
26.小明用六个体积相同、重力不同的球体,研究放入球体前后薄壁柱形容器底部受到水的压强增加量与容器对水平面的压强增加量的情况(水未溢出).他分别将球体放入盛有等质量水的相同容器中,待球体静止,通过测量和计算得到容器底部受到水的压强增加量△p水和容器对水平面的压强增加量△p地。
实验数据和实验现象见表。
(已知G A>G B>G C>G D >G E>G F)△观察序号1或2或3中的实验现象并比较△p水和△p地的大小关系,可得出的初步结论是:当放入的球体在水中沉底时,。
观察序号4或5或6中的实验现象并比较△p水和△p地的大小关系,可得出的初步结论是:。
△分析表中序号1~6的现象、数据相关条件,可得出:在盛有等质量水的相同容器中,当放入的球体时,△p地越大。
△分析表中序号1~6的现象、数据相关条件,可得出:在盛有等质量水的相同容器中,当放入的球体时,△p水相同。
参考答案1、C2、2、B3、C4、C5、B6、A7、B8、D9、定向、正、并联10、220、额定功率、0.411、马德堡半球、大、气压计12、29.4、上、29.4、漂浮13、I A>I B>I C;能;I A=I B=I C14、变小、R2、R1或电源15、一定发光、若电阻R1短路,则电流表示数变大;若电阻R2断路,则电流表示数为零。
16、△质量相同、形状不同的纸锥从同一高度下落时,锥头越尖,下落时间越短;△质量不同、形状相同的纸锥从同一高度下落时,质量越大,下落时间越短。
17、18、19、(1)1.8千克(2)1.8×10-3m320、△6V、△2.4W。
21、△1960Pa;△8千克△通过计算可知将物体放入容器无水溢出。
22、△0.4A、10Ω;△(a)AB间接电流表、CD间接电源或CD接电流表、AB接电源;(b)1.7A。
23、密度计;密度越小;托里拆利;<。
24、质量;体积;质量;多种。
25、(1)乙;不同;断开;(2)17.4;0.484。
26、△容器对水平面的压强增加量△p地大于容器底部受到水的压强△p水;当放入的球体在水中漂浮时,容器对水平面的压强增加量△p地等于容器底部受到水的压强△p水;△重力越大;△浸没体积相同。