8上期末复习题
嘉祥外国语学校初2022届八年级上册期期末复习题Unts3-4 (无听力,答案)
嘉祥外国语学校初2022届八上期木复习题Unts3-4一、单项选择(共15小题,满分15分)1.Linda is ______outgoing girl, and she is______best at dancing in her cla8s,A.a, theB. /, theC. an, the2. My school uniform is cleaner than, _____because she hardly ever washes it.A. LilyB. hisC. hers3. My mother bought me two pants as my birthday gifts. She likes both of them, but I like_____of the two.A. LongerB. the longerC. the longest4._____of my two brothers learn math well. They often help me with it.A. BothB. AllC. None5. Her grandfather is seventy years old. He still looks young, ______.A. tooB. thoughC. either6. Tina dances better than___one year ago because she practices so hard.A. she wasB. she didC. she is7.____he was tired, he still kept working hard in his office.A. As long asB. AlthoughC. Because8. I____speak English_____Lily. She has a lot of American friends to practice English with, But I don't.A. can't; as well asB. don't; as good asC. can; as well as9.RT-Market has the_____quality and ______priceA.better; the lowestB.best ; the lowestC.best ; the cheapest10.-- How do you like Wanda cinema in Chengdu?-- I think it's better than____cinema in Chengdu.A. anyB. any otherC. otherI1. Larry is_____than his sister Jane. So he can always get good grades in the exams.A. less hard-workingB. more hard-workingC. more friendly12.____you don't give up(放弃); your dreams will come true.A. As long asB. As soon asC.As well as13. Alice finds it interesting_____along the Silk Road. It is about history and culture.A. travelledB. travelingC. to travel14. If you don't____the shows______,they are fun to watch.A. take; seriouslyB.bring; outC. have; in common15. I would like to make friends_____a girl who is talented______ music.A. with, atB. to, withC. with, in二、完形填空(共10小题,满分10分)Do you like silent movies? Maybe the most famous name in the world of silent movies is Charlie Chaplin. Charlie was born in England on April 16, 1889. He was a very unlucky boy. When he was just five years old, his father was___1___and his mother was in hospital. This left young Charlie with little___ 2___.But Charlie had a nice character. He was kind and easy to be liked. So he got some small many TV programs around London. He showed great talent in acting. Then he moved to the USA in 1906, and his___4___ took an important change for the better. He got a role in a show there, and he got enough money to buy his own house.Seven years after he arrived in the USA, he got his first___5__ role in a movie. Charlie became very successful. At that time, movies were silent. Actors had to express themselves ___6___ body language. Charlie created lots of wonderful characters. His acting style was just tight for the silent movies at that time. By 1915, he made a lot of money.Charlie knew what he was good at, and he_ 7_ doing it. Even when people____ 8_ using sound in movies since 1923, he still made silent pictures. Charlie knew that the silence was a__ 9_ part of what made his movies so funny. In the 1940s, when almost everyone else had changed to sound movies, Charlie, however, was__10___ one of tho world's greatest stars in the history of movies.1. A. rich B. famous C. dead2. A. time B. hope C. use3. A. roles B. talks C. jokes4. A. life B. health C. family5. A. serious B. important C. interesting6. A. in B. from C. through7. A. thought about B. kept on C. waited for8. A. stopped B. started C. remembered9. A. necessary B. fresh C. different10. A. never B. still C. soon三、阅读理解(共5小题,满分10分)There are many ways to help improve your health like eating healthy food. Taking exercise and getting medical help. But the easiest and cheapest way to improve your health is just to sleep eight hours or more every night. The generalsleeping rule is that the younger you are, the longer sleep you need. But regardless of age, some people need to sleep more while for some a few hours is enough.The problem with sleep is that more and more people in the world are not sleeping enough.According to the World Health Organization over half the people in the world may be sleep-deprived. Having less sleep not only makes people feel tired but also causes accidents. In the United States alone, sleepy drivers cause at least 100,000 traffic accidents a year. Also sleep problems can cause medical problems such as high blood pressure(血压).Why are so many people seep-deprived? Part of the reasons may be cultural. In the American culture, people put a higher value on work than on sleep. In fact people who sleep a lot are usually seen as "lazy". Also, you can sometimes hear some people say proudly that they don 't have much time to sleep.they only sleep four or five hours a night. It seems that the less you sleep, the more work you'll do.How do we teach these people to lean the value of sleep? Perhaps they may listen to the advice of Dr.James Maas an expert(专家) in sleep.He says , Sleep is like a credit(信用卡)card. When you sleep less. you are only borrowing time. You always have to pay it back. The more hours you don't sleep, the more hours you should sleep to 'pay back' the hours on your 'sleep credit card.’ ”For those who value work more than sleep, they should listen to what a famous person once said. "Don't think you will be doing less work because you sleep during the night. That is a foolish(愚蠢的) idea which is held by people who have no imagination. You will be able to do more."1. According to the writer, the easiest and cheapest way to improve health is to____.A. eat healthy food every dayB. sleep eight hours or more every nightC. get medical help whenever necessary2. What does " steep-deprived" mean in Paragraph 2?A. Having a good sleep.B. Excited about sleep.C. Having less sleep.3. According to Dr. James Maas, what is sleep like?A. An hourB. A report.C. A credit card.4. What do the words of the famous person mean in Paragraph 5?A. Sleeping during the night is foolish.B. Sleeping during the night is helpful.C. People have no courage.5. What is the best title of the passage'?A. The Value of SleepB. The Value of StudyC. The Ways of Eating Less四、根据首字母及句意补全单词。
北师大版八年级上册期末复习专题:二元一次方程组实际应用专练(二)
八年级上册期末复习专题:二元一次方程组实际应用专练(二)1.现由A、B两种货车运输救助物资,已知3辆A车和1辆B车每次可运救助物资15吨,4辆A车和3辆B车每次可运救助物资25吨.(1)1辆A车和1辆B车一次分别可运多少吨?(2)若用A,B两种货车一次运完35吨救助物资(货车均装满),该如何安排A、B两种货车的数量?请写出所有的安排方案.2.某化妆品店老板到厂家选购A、B两种品牌的化妆品,若购进A品牌的化妆品5套,B品牌的化妆品6套,需要950元;若购进A品牌的化妆品3套,B品牌的化妆品2套,需要450元.(1)求A、B两种品牌的化妆品每套进价分别为多少元?(2)若销售1套A品牌的化妆品可获利30元,销售1套B品牌的化妆品可获利20元,根据市场需求,化妆品店老板决定,购进B品牌化妆品的数量比购进A品牌化妆品数量的2倍还多4套,且B品牌化妆品最多可购进40套,这样化妆品全部售出后,可使总的获利不少于1200元,问有几种进货方案?如何进货?3.某体育文化用品商店购进篮球和排球共200个,进价和售价如下表全部销售完后共获利润2600元.篮球排球类别价格进价(元/个)80 50售价(元/个)95 60(1)求商店购进篮球和排球各多少个?(2)王老师在元旦节这天到该体育文化用品商店为学校买篮球和排球各若干个(两种球都买了),商店在他的这笔交易中获利100元王老师有哪几种购买方案.4.工厂接到订单生产如图所示的巧克力包装盒子,每个盒子由3个长方形侧面和2个正三角形底面组成,仓库有甲、乙两种规格的纸板共2600张,其中甲种规格的纸板刚好可以裁出4个侧面(如图①),乙种规格的纸板可以裁出3个底面和2个侧面(如图②),裁剪后边角料不再利用.(1)若裁剪出的侧面和底面恰好全部用完,问两种规格的纸板各有多少张?(2)一共能生产多少个巧克力包装盒?5.5G网络,是最新一代蜂窝移动通信技术,其数据传输速率远高于以前的蜂窝网络,最高可达10Gbit/s,比4G快100倍.5G手机也成为生活、工作不可缺少的移动设备,某电商公司销售两种5G手机,已知售出5部A型手机,3部B型手机的销售额为51000元;售出3部A型手机,2部B型手机的销售额为31500元.(1)求A型手机和B型手机的售价分别是多少元;(2)该电商公司在3月实行“满减促销”活动,活动方案为:单部手机满3000元减500元,满5000元减1500元(每部手机只能参加最高满减活动),结果3月A型手机的销量是B型手机的,4月该电商公司加大促销活动力度,每部A型手机按照3月满减后的售价再降a%,销量比3月增加2a%;每部B型手机按照满减后的售价再降a%,销量比3月销量增加a%,结果4月的销售总额比3月的销售总额多a%,求a的值.6.河大附中初一年级有350名同学去春游,已知2辆A型车和1辆B型车可以载学生100人;1辆A型车和2辆B型车可以载学生110人.(1)A、B型车每辆可分别载学生多少人?(2)若租一辆A需要100元,一辆B需120元,请你设计租车方案,使得恰好运送完学生并且租车费用最少.7.某大学组织“大手拉小手,义卖献爱心”活动,该校美术社团计划购买黑、白两种颜色的文化衫进行手绘创作后出售,并将所获利润全部捐给山区困难孩子.已知美术社团从批发市场花4800元购买了黑、白两种颜色的文化衫200件,每件文化衫的批发价及手绘后的零售价如表所示:批发价(元)零售价(元)黑色文化衫25 45白色文化衫20 35(1)美术社团购进黑、白文化衫各多少件?(要求列方程组解答)(2)这批文化衫手绘创作后全部售出,求美术社团这次义卖活动所获利润.8.深圳市某小区为了以崭新的面貌迎接“创文”工作,决定请甲、乙两个装饰公司对小区外墙进行装饰维护.若由甲、乙两个公司合作,需8天完成,小区需支付费用12.8万元;若由甲公司单独做4天后,剩下的由乙公司来做,还需10天才能完成,小区需支付费用12.4万元.问:甲、乙两个装饰公司平均每天收取的费用分别是多少万元?9.为保护环境的需要,电动汽车已经成为未来汽车生产和销售的大趋势,市场上各种品牌的电动汽车如雨后春笋般涌现出来.某电动汽车经销商负责销售某种品牌的A型和B型电动汽车,今年9月份共售出该品牌汽车的A型和B型电动汽车共413台,受国庆黄金周的影响,10月份该经销商售出这两种型号的汽车达到510台,其中A型和B型汽车的销量分别比9月份增长25%和20%.(1)今年10月份,该经销商销售的A型和B型汽车分别是多少台?(2)该品牌电动汽车生产厂家为了占领市场提高销量,决定对该经销商采取销售奖励活动,若A型电动汽车每台售价为10万元,B型电动汽车每台售价为12万元,奖励办法是:每销售一台A型电动汽车按每台汽车售价的a%给予奖励,每销售一台B型汽车按每台汽车售价的(a+0.2)%给予奖励,奖励办法出台后的11月份,A型汽车的销量比10月份增加了10a%,而B型汽车受到某问题零件召回的影响,销售量比10月份减少了20a%,如果11月份该经销商共获得奖励金额为355680元,求a的值.【参考学习:我们以后会学到这样的运算:①a(b+c)=ab+ac,即单项式乘以多项式就是用单项式乘以多项式的每一项,再把所得结果相加;②(a+b)(m+n)=am+an+bm+bn,即多项式乘以多项式就是用一个多项式的每一项乘以另一个多项式的每一项,再把所得的结果相加.此题在解方程时要用到这样的运算哦!】10.某电器超市销售每台进价分别为2000元、1700元的A、B两种型号的空调,如表是近两周的销售情况:销售时段销售数量销售款A种型号B种型号第一周4台5台20500元第二周5台10台33500元(1)求A、B两种型号的空调的销售单价;(2)求近两周的销售利润.11.某电器商场销售进价分别为120元、190元的A、B两种型号的电风扇,如下表所示是近二周的销售情况(进价、售价均保持不变,利润=销售收入﹣进货成本):销售时段销售数量销售收入A种型号B种型号第一周 5 6 2310第二周8 9 3540 (1)求A、B两种型号的电风扇的销售单价;(2)若商场再购进这两种型号的电风扇共120台,并且全部销售完,该商场能否实现这批电风扇的总利润恰好为8040元的目标?若能,请给出相应的采购方案:若不能,请说明理由.12.为提高学生综合素质,亲近自然,励志青春,某学校组织学生举行“远足研学”活动,先以每小时6千米的速度走平路,后又以每小时3千米的速度上坡,共用了3小时;原路返回时,以每小时5千米的速度下坡,又以每小时4千米的速度走平路,共用了4小时,问平路和坡路各有多远.13.现有36卷相同的布料做工作服,每卷布料可制作成上衣25件,或者制作成裤子40件,一件上衣和两件裤子组成一套,问,用多少卷布料制作上衣,多少卷布料制作裤子可以使上衣和裤子正好配套?14.某商店将某种碳酸饮料每瓶的价格上调了10%,将某种果汁饮料每瓶价格下调了5%,已知调价前买这两种饮料各一瓶共花费7元,调价后买上述碳酸饮料3瓶和果汁饮料2瓶共花费17.5元,问这两种饮料调价前每瓶各多少元?15.为响应国家节能减排的号召,鼓励居民节约用电,各省先后出台了居民用电“阶梯价格”制度,如表中是某省的电价标准(每月),例如,方女士家5月份用电500度,电费=180×0.6+220×二档电价+100×三档电价=352元,李先生家5月份用电460度,交费316元.阶梯电量电价一档0﹣180度0.6元/度二档181﹣400度二档电价三档400度及以上三档电价请解答下列问题(1)若王先生家5月用电160度,则电费多少元?(2)求二档电价和三档电价分别为多少?(3)若何女士家5月用电600度,则电费多少元?16.在2月份“抗疫”期间,某药店销售A、B两种型号的口罩,已知销售800只A型和450只B型的利润为210元,销售400只A型和600只B型的利润为180元.求每只A型口罩和B型口罩的销售利润.17.某校的大学生自愿者参与服务工作,计划组织全校自愿者统一乘车去某地.若单独调配36座客车若干辆,则空出6个座位.若只调配22座客车若干辆,则用车数量将增加3辆,并有12人没有座位.(1)计划调配36座客车多少辆?该大学共有多少名自愿者?(列方程组解答)(2)若同时调配36座和22座两种车型,既保证每人有座,又保证每车不空座,则两种车型各需多少辆?18.新冠肺炎疫情期间,佩戴口罩是做好个人防护的重要举措.小明家先后两次在同一电商平台以相同的单价免邮购买了A、B两种型号的口罩.第一次购买20个A型口罩,30个B型口罩,共花费190元;第二次购买30个A型口罩,20个B型口罩,共花费160元.(1)求A、B两种型号口罩的单价;(2)“五一”期间,该电商平台举行促销活动,小明发现同样花费160元购买B型口罩,以活动价购买可以比原价多买8个,求“五一”期间B型口罩的活动价.19.小明到某服装商场进行社会调查,了解到该商场为了激励营业员的工作积极性,实行“月总收入=基本工资+计件奖金”的方法,并获得如下信息:营业员A:月销售件数200件,月总收入3400元;营业员B:月销售件数300件,月总收入3700元;假设营业员的月基本工资为x元,销售每件服装奖励y元.(1)求x、y的值;(2)商场为了多销售服装,对顾客推荐一种购买方式:如果购买甲服装3件,乙服装2件,丙服装1件共需390元;如果购买甲服装1件,乙服装2件,丙服装3件共需370元.某顾客想购买甲、乙、丙服装各一件共需多少元?20.“元旦”期间,某校组织开展“班级歌咏比赛”,甲、乙班共有学生102人(其中甲班人数多于乙班人数,且甲班人数不够100人)报名统一购买服装参加演出.下面是某服装厂给出的演出服装的价格表购买服装的套数1~50 51~100 ≥101每套服装的价格/元70 60 50如果两班分别单独购买服装,总共要付款6580元(1)如果甲、乙两班联合起来购买服装,那么比各自购买服装总共可以节省多少钱?(2)甲、乙班各有多少学生报名参加比赛?(3)如果甲班有5名学生因特殊情况不能参加演出,请你为两班设计一种省钱的购买服装方案.参考答案1.解:(1)设1辆A车一次可运x吨,1辆B车一次可运y吨,依题意,得:,解得:.答:1辆A车一次可运4吨,1辆B车一次可运3吨.(2)设应安排m辆A车,n辆B车,依题意,得:4m+3n=35,∴n=.又∵m,n均为正整数,∴,,.∴共有3种安排方案,方案1:安排2辆A车,9辆B车;方案2:安排5辆A车,5辆B 车;方案3:安排8辆A车,1辆B车.2.解:(1)设A品牌的化妆品每套进价为x元,B品牌的化妆品每套进价为y元,根据题意得:,解得:.答:A品牌的化妆品每套进价为100元,B品牌的化妆品每套进价为75元.(2)设购进A品牌化妆品m套,则购进B品牌化妆品(2m+4)套,根据题意得:,解得:16≤m≤18,∴共有3种进货方案:①购进A品牌化妆品16套,购进B品牌化妆品36套;②购进A 品牌化妆品17套,购进B品牌化妆品38套;③购进A品牌化妆品18套,购进B品牌化妆品40套.3.解:(1)设商店购进篮球x个,排球y个,依题意,得:,解得:.答:商店购进篮球120个,排球80个.(2)设王老师购买篮球m个,排球n个,依题意,得:(95﹣80)m+(60﹣50)n=100,∴n=10﹣m.∵m,n均为正整数,∴m为偶数,∴当m=2时,n=7;当m=4时,n=4;当m=6时,n=1.答:王老师共有3种购买方案,方案1:购进篮球2个,排球7个;方案2:购进篮球4个,排球4个;方案3:购进篮球6个,排球1个.4.解:(1)设甲种规格的纸板有x个,乙种规格的纸板有y个,依题意,得:,解得:.答:甲种规格的纸板有1000个,乙种规格的纸板有1600个.(2)1600×3÷2=2400(个).答:一共能生产2400个巧克力包装盒.5.解:(1)设每部A型号手机的售价为x元,每部B型号手机的售价为y元.由题意,得,解得:,答:A型手机和B型手机的售价分别是7500元和4500元;(2)设3月B型手机的销量是m部,则A型手机的销量是m部,根据题意得,[(7500﹣1500)×(1﹣a%)][m(1+2a%)]+[(4500﹣500)×(1﹣a%)][m•(1+a%)]=[m(7500﹣1500)+m(4500﹣500)](1+a%),解得:a=30或a=0(不合题意舍去),答:a的值为30.6.解:(1)设A、B型车每辆可分别载学生x,y人,可得:,解得:,答:A、B型车每辆可分别载学生30人,40人;(2)设租用A型a辆,B型b辆,可得:30a+40b=350,因为a,b为正整数,所以方程的解为:,方案一:A型1辆,B型8辆,费用:100×1+120×8=1060元;方案二:A型5辆,B型5辆,费用:100×5+120×5=1100元;方案三:A型9辆,B型2辆,费用:100×9+120×2=1140元;所以租用1辆A型8辆B型车花费最少为1060元.7.解:(1)设美术社团购进黑文化衫x件,白文化衫y件,依题意,得:,解得:.答:美术社团购进黑文化衫160件,白文化衫40件.(2)(45﹣25)×160+(35﹣20)×40=3800(元).答:美术社团这次义卖活动共获得3800元利润.8.解:设甲装饰公司平均每天收取的费用为x万元,乙装饰公司平均每天收取的费用为y 万元,依题意,得:,解得:.答:甲装饰公司平均每天收取的费用为0.6万元,乙装饰公司平均每天收取的费用为1万元.9.解:(1)设9月份,该经销商销售的A型和B型汽车分别是x台和y台,根据题意得,,解得:,∴(1+25)%x=360,(1+20)%y=150,答:今年10月份,该经销商销售的A型和B型汽车分别是360台和150台;(2)由题意得,10×360(1+10a%)×a%+12×150(1﹣20a%)×(a+0.2)%=35.568,解得:a=0.6,答a的值为0.6.10.解:(1)设A型号空调的销售单价为x元,B型号空调的销售单价为y元,依题意可得:,解得:,答:A型号空调的销售单价为2500元,B型号空调的销售单价为2100元.(2)由(1)题知A型号空调的销售单价为2500元,B型号空调的销售单价为2100元,则销售总利润为:(2500﹣2000)(4+5)+(2100﹣1700)(5+10)=10500(元);答:近两周的销售利润为10500元.11.解:(1)设A种型号的电风扇的销售单价为x元,B种型号的电风扇的销售单价为y 元,依题意,得:,解得:.答:A种型号的电风扇的销售单价为150元,B种型号的电风扇的销售单价为260元.(2)设再次购进A种型号的电风扇m台,B种型号的电风扇n台,依题意,得:,解得:.答:该商场能实现这批电风扇的总利润恰好为8040元的目标,采购方案为:购进9台A 种型号的电风扇、111台B种型号的电风扇.12.解:设平路有x千米,坡路有y千米,由题意可知,解得,答:平路有千米,坡路有千米.13.解:设用x卷布料制作上衣,y卷布料制作裤子可以使上衣和裤子正好配套,依题意,得:,解得:.答:用16卷布料制作上衣,20卷布料制作裤子可以使上衣和裤子正好配套.14.解:设碳酸饮料在调价前每瓶的价格为x元,果汁饮料调价前每瓶的价格为y元,根据题意得:,解得:.答:调价前碳酸饮料每瓶的价格为3元,果汁饮料每瓶的价格为4元.15.解:(1)160×0.6=96(元).答:王先生家5月份应交电费96元.(2)设二档电价为x元/度,三档电价为y元/度,依题意,得:,解得:.答:二档电价为0.7元/度,三档电价为0.9元/度.(3)180×0.6+220×0.7+(600﹣400)×0.9=442(元).答:何女士家5月份应交电费442元.16.解:设每只A型口罩销售利润为a元,每只B型口罩销售利润为b元,根据题意得:,解得,答:每只A型口罩销售利润为0.15元,每只B型口罩销售利润为0.2元.17.解:(1)设计划调配36座新能源客车x辆,该大学共有y名自愿者,则根据题意得,解得:答:计划调配36座新能源客车6辆,该大学共有210名自愿者.(2)设需调配36座新能源客车m辆,22座新能源客车n辆,根据题意得:36m+22n=210,∴又∵m、n为正整数∴,答:需调配36座新能源客车4辆,22座新能源客车3辆.18.解:(1)设A、B两种型号口罩的单价分别是x元,y元,由题意可得,解得:,答:A、B两种型号口罩的单价分别是2元,5元,(2)设五一”期间B型口罩的活动价为a元,由题意可得:a()=160,∴a=4,答:五一”期间B型口罩的活动价为4元.19.解:(1)根据题意得:,解得:.(2)设购买一件甲服装需要a元,购买一件乙服装需要b元,购买一件丙服装需要c元,根据题意得:,(①+②)÷4,得:a+b+c=190.答:购买甲、乙、丙服装各一件共需190元.20.解:(1)由题意,得:6580﹣102×50=1480(元).即甲、乙两班联合起来购买服装比各自购买服装共可以节省1480元.(2)设甲班有x名,乙班y名学生准备参加演出.由题意,得:,解得:.所以,甲班有56名,乙班46名学生准备参加演出.(3)∵甲班有5人不能参加演出,∴甲班有56﹣5=51(人)参加演出.方案①若甲、乙两班联合购买服装,则需要60×(46+51)=5820(元),方案②甲乙各自购买服装可以节约51×60+46×70=6280(元),方案③甲、乙两班联合购买101套服装,只需50×101=5050(元),∵5050元<5820元<6280元,因此,最省钱的购买服装方案是甲、乙两班联合购买101套服装.。
期末复习6(一次函数1)
八(上)期末复习(6)(一次函数1)基础训练:1、函数11y x =-的自变量的取值范围是_______ ,函数的自变量x 的取值范围是 。
2、下列不是一次函数的是( )。
A .x x y +=1B .)1(21-=x yC .1-=πxy D .2π+=x y3、已知自变量为x 的函数y=mx+2-m 是正比例函数,则m=________,•该函数的解析式为_________.4、直线y=2-3x 不经过第______________象限,y 随x 的增大而___________.5、一次函数22-=x y 与x 轴的交点坐标 ,与y 轴的交点坐标 ,直线与两坐标轴所围成的三角形面积为 。
6、已知一次函数y=-3x+1的图象经过点(a ,1)和点(-2,b ),则a=________,b=______.7、如图,将直线OA 向上平移1个单位,得到一个一次函数的图像,那么这个一次函数的解析式是 .8、直线y=kx+b 和直线y=-3x+8平行,且过点(0,-2)•则此直线的解析式为________.9、已知y 与4x-1成正比例,且当x=3时,y=6,写出y 与x 的函数关系式 。
10、若点(-4,y 1),(2,y 2)都在直线y=1x t 3-+上,则y 1与y 2的大小关系是 ( ) A .y 1>y 2 B .y 1=y 2 C .y 1<y 2 D .无法确定11、一次函数y kx b =+的图象如图所示,当0y <时,x 的取值范围是_________.12、如图,直线l 1、l 2的交点P 的坐标可以看作方程组 的解。
13、直线y =x -1与两坐标轴分别交于A 、B 两点,点C 在坐标轴上,若△ABC 为等腰三角形,则满足条件的点C 最多有( )。
A 、4个B 、5个C 、7个D 、8个例题探究:例1、已知点A (2,m )在直线82+-=x y 上.(1)点A (2,m )向左平移3个单位后的坐标是 ;直线82+-=x y 向左平移3个单位后的直线解析式是 ;(2)点A (2,m )绕原点顺时针旋转90°后的坐标是(3)求直线82+-=x y 绕点P (-1,0)顺时针旋转90°后的直线解析式.例2、已知直线1l :33y x =-和直线2l :362y x =-+相交于点A 。
专题02:词语(成语)的运用【2022-2023统编版八上语文期末专题复习】(解析版)
专题02 词语(成语)的运用1.下列句子中加点的词语使用不恰当...的一项是()A.老百姓对社会上以权谋私、贪污受贿等不正之风深恶痛疾。
.....B.经过近一个多月的调研,董事长认为这套方案切实可行,其他副总都随声附和....表示赞成。
C.母亲同情穷苦人,虽然自己不富裕,还周济..和照顾比自己更穷的亲戚。
D.设计者和匠师们因地制宜....,自出心裁,修建成功的园林当然各个不同。
【答案】B【解析】A.深恶痛疾:极端厌恶和痛恨。
本句指的是对于贪污腐败的痛恨,使用正确;B.随声附和:指别人说什么,自己跟着说什么,形容没有主见,属于贬义词。
在这里不符合“认为这套方案切实可行”的语境,贬词褒用,使用错误;C.周济:对穷困的人给予物质上的帮助。
在句中指的是愿意帮助他人,使用正确;D.因地制宜:根据各地的具体情况,采取行之适当的措施。
在这里指的是设计者根据园林的地点来设计园林,使用正确;故选B。
2.下列加点的成语使用无误....的一项是()A.峨眉山景色秀丽,巧夺天工....,气象万千,素有“一山有四季,十里不同天”之妙喻。
B.他仗着自己的小聪明,学习态度不认真,作业经常拖欠,妙手偶得....的好成绩,让他沾沾自喜。
C.面对反动派刽子手的死亡威胁,她坦荡如砥....地说:“我现在只求一死。
”D.莫言认为,创作必须和个人经验相结合,这样才有可能写出人物栩栩如生、语言丰富多彩、结构独具匠心....的作品。
【答案】D【解析】A.巧夺天工:形容人的精巧胜过天然,比喻技艺高超巧妙。
在此形容峨眉山的自然景色,使用对象有误;B.妙手偶得:指修养很高的人,由于偶发灵感而作出的作品,也指巧妙地办成某事。
在此形容耍小聪明的他,使用有误;C.坦荡如砥:平坦得像磨刀石一样,比喻人非常直率,做事不加犹豫,也多用来形容大面积的地方很平坦。
在此形容不惧死亡威胁的她,使用有误;D.独具匠心:指技术或艺术方面有创造性。
在此形容作品,使用正确;故选D。
八年级数学上期末复习新题型(阅读理解、新定义、找规律、作图+证明、开放性题型)精选试题
八年级数学上期末复习新题型(阅读理解、新定义找规律)精选一、阅读理解题 1.阅读材料:课堂上,老师设计了一个活动:将一个4×4的正方形网格沿着网格线.....划分成两部分(分别用阴影和空白表示),使得这两部分图形是全等的,请同学们尝试给出划分的方法.约定:如果两位同学的划分结果经过旋转、翻折后能够重合,那么就认为他们的划分方法相同.小方、小易和小红分别对网格进行了划分,结果如图1、图2、图3所示. 小方说:“我们三个人的划分方法都是正确的.但是将小红的整个图形(图3)逆时针旋转90°后得到的划分方法与我的划分方法(图1)是一样的,应该认为是同一种方法,而小易的划分方法与我的不同.”老师说:“小方说得对.”完成下列问题:(1)图4的划分方法是否正确?答:_______________.(2)判断图5的划分方法与图2小易的划分方法是否相同,并说明你的理由; 答:____________________________________________________________________. (3)请你再想出一种与已有方法不同的划分方法,使之满足上述条件,并在图6中画出来.图4图5图6图1图2图32.阅读理解:课外兴趣小组活动时,老师提出了如下问题:在△ABC中,AB=9,AC=5,求BC边上的中线AD的取值范围。
小明在组内经过合作交流,得到了如下的解决方法(如图1):①延长AD到Q,使得DQ=AD;②再连接BQ,把AB、AC、2AD集中在△ABQ中;③利用三角形的三边关系可得4<AQ<14,则AD的取值范围是_____________。
感悟:解题时,条件中若出现“中点”“中线”等条件,可以考虑倍长中线,构造全等三角形,把分散的己知条件和所求证的结论集中到同一个三角形中。
(2)请你写出图1中AC与BQ的位置关系并证明。
(3)思考:已知,如图2,AD是△ABC的中线,AB=AE,AC=AF,∠BAE=∠FAC =90°。
2022-2023学年浙教版数学八上期末复习专题 图形与坐标(学生版)
2022-2023学年浙教版数学八上期末复习专题图形与坐标一、单选题(每题3分,共30分)1.(2021八上·鄞州期末)根据下列表述,能够确定位置的是()A.甲地在乙地的正东方向上B.一只风筝飞到距A处20米处C.某市位于北纬30°,东经120°D.影院座位位于一楼二排2.(2022八上·西安月考)如果把电影票上3排6座记作(3,6),那么(6,5)表示()A.5排6座B.5排5座C.6排5座D.6排6座3.(2022八上·新城月考)2021年9月15日,中华人民共和国第十四届运动会开幕式在西安奥体中心举行,如图,如果将西安钟楼的位置记为直角坐标系的原点,下列哪个点的位置可以表示奥体中心的位置()A.(-2,3)B.(2,3)C.(-2,-3)D.(2,-3) 4.(2020八上·历下期中)如图是北京市地图简图的一部分,图中“故宫”、“颐和园”所在的区域分别是()A.D7,E6B.D6,E7C.E7,D6D.E6,D75.已知点A的坐标为(a+1,3−a),下列说法正确的是()A.若点A在y轴上,则a=3B.若点A在一三象限角平分线上,则a=1C.若点A到x轴的距离是3 ,则a=±6D.若点A在第四象限,则a的值可以为-26.(2021八上·晋中期末)如图是一只蝴蝶标本,已知表示蝴蝶两“翅膀尾部”A,B 两点的坐标分别为(-2,-3),(2,-3),则表示蝴蝶身体“尾部”C 点的坐标为()A.(0,-1)B.(1,-1)C.(-1,0)D.(2,-1)7.(2022八上·长清期中)若点P(2−m,5)在y轴上,则m的值等于()A.2B.7C.−2D.−38.(2021八上·扶风期末)已知图形A全部在x轴的上方,如果将图形A上的所有点的纵坐标都乘以-1,横坐标不变得到图形B,则()A.两个图形关于x轴对称B.两个图形关于y轴对称C.两个图形重合D.两个图形不关于任何一条直线对称9.(2021八上·川汇期末)点A(2,m)向上平移2个单位后与点B(n,−1)关于y轴对称,则m n=().A.1B.12C.−18D.1 910.(2021八上·瑞安月考)在平面直角坐标系中,将点A(a,1-a)先向左平移3个单位得点A1,再将A1向上平移1个单位得点A2,若点A2落在第三象限,则a的取值范围是() A.2 <a<3B.a <3C.a >2D.a <2或a >3二、填空题(每题4分,共24分)11.(2022八上·城阳期中)如图是一台雷达探测相关目标得到的结果,若记图中目标A的位置为(2,90°),目标B 的位置为(4,30°),现有一个目标C的位置为(3,m°),且与目标B的距离为5,则目标C的位置为.12.(2022八上·城阳期中)已知点M(2m−1,−3),点N(5,2),直线MN∥y轴,则m的值为.13.(2022八上·西安月考)点A(m−1,2m−3)在第一、三象限夹角的角平分线上,则m的值为.14.(2021八上·巴彦期末)点P(a,−3)与Q(2,b)关于y轴对称,则a b的值为.15.(2020八上·深圳期中)如图,已知A1(0,1),A2(√32,−12),A3(−√32,−12),A4(0,2),A5(√3,-1),A6(−√3,-1),A7(0,3),A8(3√32,−32),A9(−3√32,−32)……则点A2010的坐标是16.(2021八上·永吉期末)若(x+2)(x−3)=x2+bx+c,其中b,c为常数,则点P(b,c)关于x 轴的对称点的坐标为.三、解答题(共8题,共66分)17.(2021八上·平远期末)小明和朋友到人民公园游玩,回到家后,利用平面直角坐标系画出了公园的景区地图,如图所示.可是他忘记了在图中标出原点和x轴、y轴,只知道游乐园D的坐标为(1,﹣3),请你帮他画出平面直角坐标系,并写出其他各景点的坐标.18.(2021八上·莲湖期中)已知点A(m﹣2,5)和B(3,n+4),A,B两点关于y轴对称,求m﹣n 的值.19.(2021八上·横县期中)如图,利用关于坐标轴对称的点的坐标的特点,画出与△ABC关于x轴对称的图形.20.(2021八上·海曙期末)在如图所示的正方形网格中,每个小正方形的边长为1,格点三角形(顶点是网格线的交点的三角形)ABC的顶点A,C的坐标分别为(-4,5),(-1,3).⑴请在如图所示的网格平面内作出平面直角坐标系;⑴请作出⑴ABC关于y轴对称的⑴A′B′C′;⑴写出点B′的坐标.21.已知点P(3a−15,2−a).(1)若点P位于第四象限,它到x轴的距离是4 ,试求出a的值:(2)若点P位于第三象限且横、纵坐标都是整数,试求点P的坐标.22.(2022八上·台州月考)如图,平面直角坐标系中,A(﹣2,1),B(﹣3,4),C(﹣1,3),过点(1,0)作x轴的垂线l.(1)作出⑴ABC关于直线l的轴对称图形△A1B1C1;(2)直接写出A1(,),B1(,),C1(,);(3)在⑴ABC内有一点P(m,n),则点P关于直线l的对称点P1的坐标为(,)(结果用含m,n的式子表示).23.(2021八上·黑山期中)如图回答下列问题:(1)如图①所示,请用有序数对写出棋盘上棋子“帅、黑车、炮”的位置(把列号写在前面,行号写在后面).(2)如图②所示把O点移动到棋子“仕”的位置时,用有序数对写出棋子“仕、相、黑马”的位置(把列号写在前面,行号写在后面)(3)如图②,已知棋子“将”的位置是(2,8),棋子“黑马”的位置是(4,3),规定列在前,行在后,请你在棋盘上确定A(0,0)点的位置,棋子“红马”的位置是什么?24.(2021八上·佛山月考)在如图的正方形网格中,每一个小正方形的边长为1,格点三角形ABC(顶点是网格线交点的三角形)的三个顶点的坐标分别为A(1,1),B(4,2),C(3,4)(1)请在图中的网格平面内建立平面直角坐标系,并将△ABC画出来.(2)在图中找一点D,使AD=√26,CD=√13,并将点D标记出来.(3)在x轴上找一点P,使PA+PB的值最小,请直接写出点P的坐标.(4)在y轴上是否存在点Q,使得S△AOQ=12S△ABC,如果存在,求出点Q的坐标,如果不存在,说明理由.答案解析部分1.【答案】C【知识点】用坐标表示地理位置【解析】【解答】解:根据题意可得,A.甲地在乙地的正东方向上,无法确定位置,故答案为:A不合题意;B.一只风筝飞到距A处20米处,无法确定位置,故答案为:B不合题意;C.某市位于北纬30°,东经120°可以确定一点的位置,故答案为:C符合题意;D.影院座位位于一楼二排,无法确定位置,故答案为:D不合题意.故答案为:C.【分析】根据在平面内要确定一个点的位置,必须是一对有序数对,再对各选项逐一判断即可. 2.【答案】C【知识点】有序数对【解析】【解答】解:把3排6号的电影票记作(3,6),那么(6,5)表示的电影票号是:6排5号.故答案为:C.【分析】根据题意可得数对中的第一个数表示排,第二个数表示号,据此解答.3.【答案】B【知识点】用坐标表示地理位置【解析】【解答】解:由题意可得:奥体中心的位置可以为(2,3).故答案为:B.【分析】由于奥体中心在第一象限,而第一象限的坐标符号为正正,据此解答即可.4.【答案】C【知识点】有序数对【解析】【解答】如图所示:图中“故宫”、“颐和园”所在的区域分别是:E7,D6.故答案为:C.【分析】直接利用已知网格得出“故宫”、“颐和园”所在的位置。
苏科版2021年秋八年级(全一册)上学期期末总复习物理过关高频题(附答案)
苏科版2021年秋八年级(全一册)上学期期末总复习物理过关高频题姓名:学号:一、单选题1.关于声现象的描述,下列说法错误的是()A.甲图:把耳朵贴在桌面上,听到轻敲桌子的声音,说明桌子能传声B.乙图:超声波清洗机正在清洗眼镜,说明超声波能传递能量C.丙图:戴上防噪声耳罩,目的是防止噪声进入人耳D.丁图:使用声学仪器接收超声波,可以确定地震、火山爆发的方位2.小红吃雪糕时,看到雪糕周围冒“冷气”,由此她联想到了日常生活中我们会经常看到烧开水时从壶嘴冒“热气”的情景。
以下是她对“冷气”和“热气”的思考,其中正确的是()A.“冷气”和“热气”本质是相同的,他们都是汽化生成的水蒸气B.“冷气”和“热气”本质是不同的,前者是小水珠,后者是水蒸气C.“冷气”和“热气”本质是不同的,前者是液化形成的,后者是汽化形成的D.“冷气”和“热气”本质是相同的,但水蒸气来源不同,前者来源于空气中,后者是由热水汽化生成3.早在战国时期,我国古代著名教育家、思想家墨子就在研究小孔成像的现象。
如图所示,若用蜡烛作为光源,在木板上钻一个小孔,发现光线透过小孔在墙壁上形成像,下列说法正确的是()A.经过调节,像的大小可以等于物的大小B.木板上的小孔一定是圆形的C.保持蜡烛和墙位置不变,将木板向墙的方向移动,蜡烛在墙上的像会变大D.蜡烛在墙上形成的像是正立的4.如图所示,为防疫新冠病毒,学校在用测温枪检测体温。
测温枪的学名是“红外线测温仪”或者“红外线辐射测温仪”。
它的原理是:被动吸收目标的红外辐射能量,从而获得物体温度数值。
下列有关的说法不正确的()A.不能通过肉眼观察到红外线B.红外线测温仪是通过测温枪发出红外线来测体温C.验钞机利用紫外线辨别钞票的真伪,不是红外线D.红外线测温仪测体温说明红外线能传递能量5.如图所示的四种情景中,属于光的反射现象的是()A.湖中的倒影B.杯中的筷子C.日食D.放大镜下的手指6.如图所示,装香水玻璃瓶的透明瓶盖,设计有多种形状,其中阳光透过瓶盖会导致香水温度较快升高的是()A.B.C.D.7.在操场直跑道上进行遥控小车比赛,甲、乙两车从t=0s时由同一起点同方向运动,两者运动的s﹣t图像分别如图中的甲、乙所示,下列判断正确的是()A.在5~10s内甲车做匀速直线运动B.在0~5s内乙车的速度是2m/sC.t=10s时两车的速度相等D.t=10s后乙车超过甲车二、填空题8.温度计是根据液体的___________原理制成的。
部编版2019-2020学年第一学期八年级语文期末复习试卷含答案
部编版2019-2020学年第一学期八年级语文期末复习试卷含答案一、古诗文积累与运用:(15分)1.几处早莺争暖树,。
2.烽火连三月,。
3.,病树前头万木春。
4.《次北固山下》一诗中,诗人在对自然景物的描写中融入生活理趣的名句是:,。
5.《过零丁洋》中最能体现诗人“舍生取义,杀生成仁”的民族气节的诗句是:?。
6.《游山西村》既写出春社欢快,又表达了民风淳朴可爱的诗句是:,。
7.陶渊明在《桃花源记》中虚构了一个令人向往的世外桃源,千百年来散发着不朽的魅力。
文中表现桃源人与外人间隔,不知如今是何年何月之意的句子:,。
8.学校食堂的菜品公示栏上有如下内容:(4分)①请将公示栏中的两个错别字:改为;改为。
(2分)②就上面的错别字,你准备给食堂师傅提出来,请他们改正。
你将怎么说?(2分)。
二、阅读:(一)文言文阅读(15分)甲.课内文言文阅读(10分)《论语》九则孟武伯问孝。
子曰:“父母唯其疾之忧。
”子游问孝。
子曰:“今之孝者,是谓能养。
至于犬马,皆能有养;不敬,何以别乎?”子曰:“父母在,不远游,游必有方。
”子曰:“父母之年,不可不知也。
一则以喜,一则以惧。
”子曰:“巧言令色,鲜矣仁!”子曰:“德不孤,必有邻。
”子曰:“,。
”子曰:“君子坦荡荡,小人长戚戚。
”子贡问曰:“有一言而可以终身行之者乎?”子曰:“其恕乎!己所不欲,勿施于人。
”9.《论语》是记录的一部书,共20篇,是家经典著作之一。
(1分)10.解释下列加点的词语在文中的意思。
(2分)①是谓能养.()②游必有方.()③德不孤,必有邻.()④君子喻.于义()11.补全文中第七则写在下面横线上(2分)12.如何理解“德不孤,必有邻”?(2分)13.“己所不欲,勿施于人”是最早由儒家提倡的待人接物的处世之道。
请你联系生活体验,谈谈自己的观点。
(3分)乙.课外文言文阅读(5分)沐则心覆文公之出也①,竖头须②,守藏者也③,不从④。
公入⑤,乃求见,公辞焉以沐⑥。
2023-2024学年道德与法治八年级上册期末复习试题(含答案)
2023-2024年道德与法治八年级上册期末复习试题一、单选题(共18小题)1.下列诗句体现的社会关系与其建立的基础对应不正确的是()A.“儿行千里母担忧,夜半灯前念远游。
”——血缘关系B.“同乡同姓仍同榜,喜见烟中跨灶楼。
”——地缘关系C.“两心宜一体,同舍又邻居。
”——业缘关系D.“饮其流者怀其源,学其成时念吾师。
”——业缘关系2.研学旅行继承和发展了我国传统游学“读万卷书,行万里路”的教育理念和人文精神,成为素质教育的新内容和新方式。
研学旅行寓“教”于“行”,边走边学,开阔视野,增长见识,受到了师生的普遍欢迎。
这说明研学旅行有利于()①挖掘自身潜力,实现自我超越②实现学以致用,促进知行合一③丰富人生阅历,提升自身素质④提前进入社会,迎接各种考验A.①②B.①④C.②③D.③④3.预防出现漫画中的现象,我们未成年人应该()①接受父母老师及有关部门的教育引导,做到对自己负责②定好上网时间,并请父母监督③培养坚强意志,坚决不上网④丰富网络知识,提高辨别能力和自控力A.①②④B.①②③C.①③④D.②③④4.2023年暑期来临之际,为教育引导中小学生绿色上网、文明上网,树立网络安全意识,提高预防网络沉迷能力,多地教育局持续开展2023年预防未成年人网络沉迷宣传教育活动。
关于防治青少年沉迷网络,下列说法正确的是()①网络迅猛发展,青少年离不开网络也很正常②加强网络平合的监管,净化网络环境③网络不是法外地,网络是青少年学习法律的主阵地①高空抛物是一种严重的犯罪行为②加强自我防范就能避免遭受侵害③要遵守法律法规,杜绝不良行为④要提高思想道德修养,举止文明A.①②B.①③9.下列四个案件的违法性质及维权途径正确的是(体现了()①关注社会,关心国家大事②在社会课堂中成长③管理社会的亲社会行为④关心社会,自觉承担社会责任A.①②③B.①③④C.①②④D.②③④14.“中国梦是民族的梦,也是每个中国人的梦。
”“国家好、民族好、大家才好。
部编八年级语文上册期末复习《阅读理解》专项练习题(含答案)
部编八年级语文上册期末复习《阅读理解》专项练习题(含答案)(甲)至于夏水襄陵,沿溯.阻绝。
或王命急宣,有时朝发白帝,暮到江陵,其间千二百里,虽乘奔御风,不以疾也。
春冬之时,则素湍绿潭,回清倒影,绝巘多生怪柏,悬泉瀑布,飞漱其间,清荣峻茂,良多趣味。
每至晴初霜旦,林寒涧肃,常有高猿长啸,属引.凄异,空谷传响,哀转久绝。
故渔者歌曰:“巴东三峡巫峡长,猿鸣三声泪沾裳。
”(节选自郦道元《三峡》)(乙)登山里许,飞流汩然下泻,俯瞰其下,亦有危壁,泉从壁半突出,疏竹掩映,殊有佳致。
然业已上登,不及返顾.,遂从三姑①又上半里,抵换骨岩,岩即.幔亭峰②后崖也。
岩前有庵。
从岩后悬梯两层,更登一岩。
岩不甚深,而环绕山巅如叠嶂。
土人新以木板循岩为室曲直高下随岩宛转。
(节选自《徐霞客游记》)(注)①三姑:地名。
②幔亭峰:山峰名。
1.解释下列加点词在文中的意思。
①沿溯.阻绝溯:②属引.凄异引:③不及返顾.顾:④岩即.幔亭峰后崖也即:2.下列对文中画横线部分的断句,正确的一项是()A.土人新以木板循岩为室/曲直高下/随岩宛转B.土人新/以木板循岩为室/曲直高下随岩宛转C.土人新以木板循岩/为室曲直高下/随岩宛转D.土人新/以木板循岩为室曲直/高下随岩宛转3.把文中画横线的句子翻译成现代汉语。
其间千二百里,虽乘奔御风,不以疾也。
4.甲文写“水”,各写了三峡“四时之水”的什么特点?乙文写“山”,作者前往“换骨岩”途中俯瞰到什么“佳致”?请简要概括。
生于忧患,死于安乐舜发于畎亩之中,傅说举于版筑之间,胶鬲举于鱼盐之中,管夷吾举于士,孙叔敖举于海,百里奚举于市。
故天将降大任于是人也,必先苦其心志,劳其筋骨,饿其体肤,空乏其身,行拂乱其所为,所以动心忍性,曾益其所不能。
人恒过,然后能改;困于心,衡于虑,而后作;征于色,发于声,而后喻。
入则无法家拂士,出则无敌国外患者,国恒亡。
然后知生于忧患而死于安乐也。
5.解释下列加点词语在句子中的意思。
八上go for it英语期末复习B卷习题及答案
大家好
1
Unit 1
--Hi, Tina, I __h_e_a_rd___ that you went to the _m__o_u_n_ta_i_n_s on vacation. __H_o_w___ did you like it? --Everything was interesting, I never felt __b_o_r_e_d. --__W__h_o_ did you go there with?
--It was my second time to climb the mountain, so I
went there with _n_o_b_o_d_y_, only myself. --Did you do _a_n_y_t_h_i_n_ginteresting?
--Of __c_o_u_r_s_e_. I dids_o_m__e_th__in_g I like. But at night there was _n__o_th_i_n_g_ much to do __b_u_t__ sleep.
--What did you like best? --I enjoyed _s_w__im__m_i_n_g__ in the sea. And I was also
__in_t_e_r_e_s_te_d_ in living in Bali. --What __e_ls_e____ did you do? --I speshopping in Bali. That’s
第二章 声现象【2021秋八上物理期末复习真题精练】(解析版)
第二章声现象【2021秋八上物理期末复习真题精练】学校:___________姓名:___________班级:___________考号:___________一、单选题1.(2021·广东广州·中考真题)如图,甲鼓发声时鼓皮每秒振动的次数比乙的少,单、乙相比,甲鼓皮()A.发声的响度一定较大B.发声的音调一定较低C.振动的振幅一定较小D.振动的频率一定较高【答案】B【详解】D.频率是物体在单位时间内振动的次数,根据题意知道,甲鼓发声时鼓皮每秒振动的次数比乙的少,说明甲鼓振动的频率比乙鼓小,故D错误;B.音调是指声音的高低,音调跟频率有关,频率越大,音调越高;频率越小,音调越低;由于甲鼓振动的频率比乙鼓小,所以甲鼓发声的音调一定较低,故B正确;AC.响度是由发声体振动的幅度决定的,振幅越大、响度越大,根据题意,不能判断两鼓的振幅,故不能判断响度,故AC不符合题意。
故选B。
2.(2021·辽宁鞍山·中考真题)我市某校举行庆祝中国共产党建党100周年合唱活动,以下四个选项中用声学知识解释正确的是()A.演唱者的歌声是由空气振动产生的B.主持人使用话筒是为了提高声音的音调C.嘹亮的歌声是通过空气传到现场观众耳中的D.禁止观众在礼堂中大声说话是在人耳处减弱噪声的【答案】C【详解】A.歌声是由演唱者的声带振动产生的,故A错误;B.主持人使用话筒是为了提高声音的响度,故B错误;C.声音的传播需要介质,嘹亮的歌声是通过空气传到现场观众耳中的,故C正确;D.禁止观众在礼堂中大声说话是在声源处减弱噪声,故D错误。
故选C。
3.(2021·山东威海·中考真题)帝企鹅繁殖期间,企鹅妈妈捕鱼归来,能在几十万只企鹅嘈杂的叫声中精准地分辨出孵蛋的企鹅爸爸的声音,它主要利用了声音的什么性质()A.音调B.音色C.响度D.频率【答案】B【详解】声音的特性有响度、音调、音色。
八年级英语上学期期末试卷真题(人教版含答案)
初二上学期期末英语试卷一、阅读理解1. A.at 2: 00 P .M., on Sunday B.at 11:00 A.M., on SundayC.at 2:00 P .M., on SaturdayD.at 11:00 A.M., on Saturday(1)A.2 B.3 C.4 D.5(2)A.ad for fair B.food menu C.story book D.study report(3)Do you know Beijing Country Fair (集市)? This week, you can enjoy the magic show and thefun of DIY (Do It Yourself). It offers you healthy food for free. Come and see it for yourself!Schedule for Beijing Country FairFRI 11:00 A.M. 12:00 A.M.1:00 P .M.2:00 P .M.3:00 P .M.Free tasteHand-made cookies---------------5-6-year-olds 7-9-year-olds 10-14year-oldsSAT Pet Parades (游行)Hand-made soap---------------9-10-year-olds11-12-year-olds 13-14-year-oldsTeddy's afternoon teaSUN Hand-made activities DIY old clothes Magic showAccording to the passage, you can enjoy the magic show .People can enjoy kinds of activities on Sunday.You will probably find this schedule from a/an .2.You may not have heard the words freshman fifteen before, but they are very important forstudents who are entering university. A freshman is a first-year college student. And the fifteen means fifteen pounds—the fifteen pounds (about 7 kg) of weight (体重)many American students will gain (增加)in their first year at college. There are a few reasons why first-year college students often gain a few pounds. The most common reason may be that many college students just don't eat right.However, if you're careful, it's really quite easy for you not to put on fifteen pounds.(本大题共15小题,每小题2分,共30分)期末复习与测试A.B.C.D.(1)A.B.C.D.(2)A.join a sports team B.study before doing sportsC.exercise less and study moreD.do sports with their friends(3)A.B.C.D.(4)Here are some ideas for staying healthy at college:• Eat only when you are hungry, not when you're bored.• Fill half of your plate with vegetables.• Don't eat desserts that are full of sugar. Have some fruit after dinner instead.• Try not to eat while you study, or keep healthy snacks like baby carrots nearby.• Always eat at the dinner table and never in front of the TV or the computer.• Choose water over sugary drinks.• Try to get out of your room often for some fresh air and exercise.Remember that the freshman fifteen can happen to anyone. Make a deal with your friends to try and eat healthy food together. Walking, running and playing sports are always more fun with friends,too. Help each other eat right and stay fit and you can have a happy and healthy freshman year.The "freshman fifteen" means .fifteen students who eat junk foodweight that high school students gainweight that first-year college students gainfifteen pounds of food that first-year students eat According to this passage, which student will probably get freshman fifteen?Sally usually eats some fresh fruit after dinner.Ann eats ice-cream and cakes after dinner every day.Tom plays basketball with his friends every morning.John never eats anything when he does his homework.The writer suggests that students should .The writer of the passage would probably agree with the idea that .students should study outdoors more oftenstaying healthy is easier with friends' helpall the college students will gain 15 poundssome students can eat anything they want期末复习与测试3. A.①② B.③④ C.①③ D.②④(1)A.Cleaning the room. B.Keeping the air fresh.C.Leaving enough space.D.Turning on the lights.(2)(3)COVID-19(新冠肺炎)stopped people from working for several months in 2020. These days,people have returned to work. What can we do to keep ourselves safe? Here is some advice.When commuting (上下班)Don't take public transport. Try to walk, cycle or drive to your office instead.If you have to take public transport, you shall wear a face mask (口罩)through the ride and try not to touch anything in the subway or on the bus with your hands.Entering the workplaceWear a face mask and receive body temperature check before entering the office building. You must pass the body temperature check before being allowed in. Wash hands in time.If you have a fever, please go to the fever clinic of a hospital at once.Using an elevator (电梯)Avoid using the elevator if you are going to or leaving lower floors. Use the stairs instead.Don't stand near the doors while waiting. Do not stand face to face with people while waiting.In officesOpen windows to let fresh air in during the day. Do it three times a day for 15 minutes to half an hour each time so that you'll have less chance of getting ill. Ventilation can stop the virus (病毒)from building up.Keep healthy habits such as eating a healthy diet, exercising and getting enough sleep. They can help you have a strong body.What must you do before entering the workplace?① Wear a face mash② Use an elevator.③ Receive body temperature check.④ Go to the fever clinic of a hospital.What does the underlined word "Ventilation " probably mean?Which of the following is a good way to keep you strong according to this passage?期末复习与测试A.Opening the window.B.Getting long sleep.C.Keeping healthy habits.D.Doing more outdoor activities.A.B.C.D.(4)What is the best title for the passage?How to Improve Health.Some Ways to Keep Away from COVID-19.Please Get the Body Temperature Check.The Importance of Fighting Against COVID-19.4. A.a large city in China B.a system of waterwaysC.a small river in HangzhouD.part of the Great Wall of China(1)ed in many ways B.not used anymoreC.mainly used for tripsD.hardly used for transporting food(2)A.China B.the Grand Canal(3)Most people have heard of the Great Wall of China, but not many people outside of China know about the Grand Canal. This man-made waterway—known in China as Da Yunhe is 1, 700 kilometers long and some parts of it are more than 2, 000 years old. It links (连接)the north of China with Hangzhou, a city in the southern part of the country. It's the longest man-made waterway in the world.It was built as a way to transport (运输)food from the rich land in China's south to cities in the north. In fact, it's not one canal, but a system (系统)of canals and rivers linked together.It's still an important part of the transport system in China. Thousands of boats use it every day to transport food and many other kinds of things.China is now doing new work on the Grand Canal. It is making parts of it deeper, so bigger ships can use. The canal will also help to move water. There is a lot of rain in the south of China, but not so much in the north. The canal will carry lots of water from the south to the north.The Grand Canal is much less famous than the Great Wall, and not very many visitors know it.But it sees the changes of Chinese history. It's possible logo on a trip along some of the oldest parts of the canal. Visitors can see beautiful parts of China that others don't see.Da Yunhe is .Now the Grand Canal is .In the last paragraph the underlined word "it" refers to .期末复习与测试C.HangzhouD.the Great Wall of ChinaA.B.C.D.(4)What is the writer's main purpose (目的)in writing this passage?To describe the trip on the Grand Canal.To introduce the past and present of the Grand Canal.To show the Grand Canal is more important than the Great Wall.To explain why few people in China know about the Grand Canal.二、信息匹配(本大题共5小题,每小题2分,共10分)5.Top 5 Must Have Apps in China for TravelersWhat apps should I have for a trip to China? With no Facebook, Google, or WhatsAPP , you may worry about how you can look around or stay in touch with friends and family during your China trip.Fear not! The following apps can help you.1This is the top one for you to get in touch with your local Chinese friends. Nowadays, WeChat ID is more popular than your phone number in China. Through the app, we can send texts, voice messages, photos, and make phone and video calls to friends anywhere you go for free.2You just tell the app where to go, the nearest taxi driver can get the message quickly so that you don't need to go to the street to wait for a taxi.3You can buy anything and everything, from clothes and food to computers, pets and even real houses. The best part is that it is cheaper than in the stores and you will get in a very short time,sometimes even on the same day you ordered it!4How do you relax after a day's work? "Youku" offers you a great selection of Chinese, Korean and foreign dramas, movies, songs, dances and other TV shows for free!5期末复习与测试A. B. C. D. E. F.With Alipay, you don't need to take your bank cards. It could be accepted in most Chinese shopsand restaurants. Credit card payments, daily life bills and many city services can also be found in this app. Just take your phone.Feel free to shop for anythingThe best entertainment app for relaxingPay with your phone almost everywhereThe easiest way for you to join a team for funAn app helps you save your time to take a taxiKeep in touch with friends and family at home三、完形填空(本大题共15小题,每小题1分,共15分)6.1.2.Twenty years ago, when Angel and I were studying in college, our professor(教授)taught us alesson we've never forgotten. On the last day of class 1 graduation(毕业), she walked into the classroom to teach the 2 lesson, which she called "a life lesson about mindset(心态)and different ways we 3 things". As she held up a glass of water over her head, everyone thought she would talk about the common "glass half empty or glass half full" lesson. 4 , with a smile on her face, our professor asked, "How 5 is this glass of water I'm holding(握着)?"All the students felt surprised and 6 were from one ounce (about 28g) to a few pounds. After a few moments, she 7 , "The weight(重量)of this glass is not important in my opinion. It all depends on 8 I hold it. If I hold it for a minute or two, it's quite light. If I hold it for an hour, I might feel really tired. If I hold it for a day, my 9 will be unable to stand it, making me drop the glass to the 10 . In each case, the weight of the glass doesn't 11 , but the longer I hold it, the heavier it feels to me."As most of us students agreed, she said, " 12 worries, failures, and problems are very much 13 this glass of water. Think about them for a little while and 14 happens. Think about them a bit 15 and you begin to feel bad. Think about them all day long, and you will feel you are weak. You can't do anything else until you drop them."A.sinceB.untilC.beforeD.afterA.finalB.firstC.pastD.next期末复习与测试3.4.5.6.7.8.9.10.11.12.13.14.15.A.look up B.look for C.look at D.look afterA.SoB.ThoughC.BecauseD.HoweverA.specialefulC.heavyD.clearA.questionsB.answersC.messagesD.reasonsA.askedB.repliedC.talkedD.suggestedA.how oftenB.how soonC.how muchD.how longA.legB.armC.headD.footA.floorB.doorC.windowD.wallA.leaveB.deleteC.changeD.shareA.OurB.YourC.TheirD.MyA.withB.fromC.aboutD.likeA.nothingB.anythingC.everythingD.somethingA.fasterB.longerC.harderD.slower四、语法填空(本大题共10小题,每小题1分,共10分)7.One day, when Henry was working in a restaurant, a snake suddenly appeared and bit (咬)his hand.A few days earlier the snake arrived from Asia in a box of 1 (watermelon). It climbed out and moved away."It suddenly bit me again. I threw (扔)it across the kitchen, and saw it was on a table."Henry 2 (quick) picked up his mobile phone and took a photo with it. Then the snake 3 (move) to the fridge.When Henry was trying to find the snake, his hand began to feel hurt (疼痛). He ran fast to hospital. As the doctors were checking him, it got even 4 (bad). But they could not help him 5 they did not know what kind of snake bit him.Suddenly Henry remembered 6 (take) the photo. The doctors sent the photo 7 a zoo.As soon as they learnt what kind of snake bit him, they gave Henry the right medicine, and he left hospital 8 next day.期末复习与测试"So 9 a snake bites you, take out your mobile phone or camera."says Henry. "The most important thing is to take 10 (it) photo, and show the photo to the doctors. Oh, but as you know, the snake won't smile!"五、首字母填空(本大题共10小题,每小题1分,共10分)8.This English a is difficult for me to read because there are many new words.9.My birthday is on the way. I'd like to invite some friends to c .10.My mother asked me to put those dirty clothes into the washing m .11.If you listen c you can understand what the teacher says in class.12.I broke my mum's favorite cup. That made her really a .13.Of the three movie theaters, the Screen City is the c to my home. It only takes 5 minutes.期末复习与测试14.There is something wrong with my t . I must see a dentist as soon as possible.15.Tina is t in singing. She can sing very well at a young age.ing your mobile phone while driving is very d .17.To welcome the New Year, the students are busy p the party for it at present.六、书面表达(本大题共1小题,共15分)18.假如你是李杰,最近收到外国好友Tony的电子邮件。
人教版英语八年级上册-期末复习 专题02 完形填空
【期末复习专题卷】人教版英语八年级上册专题02完形填空一、完形填空阅读短文,从各题A、B、C、D中选出能填入对话中相应空白处的最佳答案。
Long, long ago there was a young man named Niulang. One day he ___1___ a beautiful girl, Zhinv, the Goddess’s seventh daughter. She had just run away from the heaven(天国)because she feel ___2___ every day. Soon Zhinv and Niulang loved each other. Niulang worked in the field and Zhinv wove(织布)at home. They lived a happy life and gave birth to a boy and a girl. ___3___, the Goddess found out the fact and ordered Zhinv to go back to heaven. After Zhinv left, Niulang was quite sad. With the help of his magic cow, Niulang flew to heaven with his ___4___ children to look for his wife. The Goddess knew about it and was very ___5___. Taking out her hairpin(发簪), the Goddess created a wide ___6___. From then on, Niulang and Zhinv couldn’t stay together. They had to live on the two sides of the river.However, their true love ___7___ all the magpies(喜鹊)in the world, ___8___ thousands of magpies would fly up to make a bridge for them once a year. At last the Goddess agreed ___9___ to meet each other on the 7th day of the 7th lunar month. Today it is a great ___10___ for Chinese young people to show their love.1.A.met B.told C.talked D.thanked 2.A.lucky B.bored C.different D.interested 3.A.Luckily B.Unluckily C.Carefully D.Hardly 4.A.two B.three C.four D.one 5.A.sorry B.angry C.happy D.excited 6.A.river B.hole C.seat D.road 7.A.changed B.moved C.surprised D.promised 8.A.so B.but C.though D.because 9.A.us B.him C.her D.them 10.A.day B.way C.lesson D.habitLucy and Lily are twin(双胞胎) sisters. Their birthday is on August 8th ____11____ it is coming soon. Lucy and Lily are talking(讨论) about it now.Lucy says, “Every year (年) we ____12____ a birthday party and eat a birthday cake.It’s always the same. Sounds ____13____ , doesn’t it? This year I ___14___ a different (不同的) one.”“What do you want to do ____15____ that day” Lily asks.“Do you kno w our classmate David? His mother is not healthy. She must see a doctor. but she doesn’t have much money (钱). So I want to help ____16____ . What do you think of it, Lily?”“Great!” says Lily. “I think a flea market (跳蚤市场) is good. We can see many____17____ there—radios, clothes and books.”“Yes, you’re ____18____. People can ____19____ them and we can get some money and help David’s mother. Let’s do it,” says Lucy.When their ____20____ know about this, they want to help David’s mother, too. Lucy’s family are really nice.11.A.but B.and C.or D.so 12.A.find B.take C.have D.like 13.A.boring B.busy C.easy D.big 14.A.spell B.know C.get D.want 15.A.on B.in C.of D.with 16.A.him B.me C.her D.us 17.A.planes B.things C.phones D.numbers 18.A.difficult B.relaxing C.right D.happy 19.A.buy B.eat C.play D.love 20.A.friends B.sons C.teachers D.parentsLet me tell you some new friends. The Smiths are my ___21___ neighbors(邻居). There are ___22___ people in their family. They are Mr. Smith, Mrs. Smith and their two___23___, Anna and Peter.Mr. Smith is an English teacher. His classes are ___24___. All his students thinkhe___25___ very fun. Mrs. Smith ___26___ in a big hospital. She goes to work early every day. Anna and Peter are in my school, and we are classmates. Anna is very ___27___ at math. So she often helps me ___28___ my math. Peter loves sports ___29___ plays basketball every day. His favorite basketball ___30___ is Yao Ming. How do you feel about them? 21.A.new B.old C.bad D.right22.A.two B.three C.four D.five 23.A.students B.children C.sons D.daughters 24.A.free B.difficult C.hard D.interesting 25.A.am B.is C.are D.be 26.A.works B.loses C.gets D.has 27.A.well B.bad C.good D.nice 28.A.with B.to C.for D.on 29.A.but B.or C.then D.and 30.A.bag B.star C.clothes D.name根据短文内容,从各题的四个选项中选择一个最佳答案。
广州英语八年级上期末各单元复习题(含答案)
八年级(上)Unit1综合知识专练一、单词和词组归纳与练习I. 根据句意及首字母提示填写单词,使句子完整、通顺.1. I didn't w ___________ first prize in the competition。
I felt sorry for it.2. Edison was famous as a great i___________. He invented many things。
3. The young girl wants to be a s___________ in the future。
4。
She shows great i ___________ in singing。
She can learn a song in a short time。
5。
Our school subjects i___________ Chinese,Maths, English,history, Geography, physics,chemistry and biology.6。
The remote control is an important I___________。
We can turn on or off the TV with it。
7. N___________ will believe that he is in trouble because he has already told a lot of lies。
8. Mary was b___________ in a happy family. Everyone loves her.9。
P___________ this book will give you some useful advice on your studies.10. H___________ brains can produce lots of new ideas,so we are smarter than computers。
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小明同学用蓝色墨水笔在白纸上写了 一些字, 一些字,他在只有红色灯光的暗室里 红 看到的纸是_________色,看到的字 看到的纸是 色 黑 是_________色。 色
“九寨沟”的镜海中有着“鱼在天上飞,鸟 九寨沟”的镜海中有着“鱼在天上飞, 九寨沟 在水中游”的美景奇观,这水中画面的“ 在水中游”的美景奇观,这水中画面的“鱼” 是由于光的_________形成的 虚 形成的_________ 是由于光的 折射 形成的 (填“虚”或“实”)像;“鸟” 是由于光 反射 形成的_________(填“虚” 的_________形成的 形成的虚 ( 或“实”)像。
(5)本实验应用 玻璃板 ) 代替平面镜做 实验, 的特点, 实验,是因为玻璃板具有 透明 的特点, 准确的找到像的位置 。 便于 (6)本实验用到的测量工具是 刻度尺 ) 目的是为了测量 像与物到平面镜的距离 (7)若在实验中观察到两个像的可能原因是 ) 玻璃板太厚了
小李把一个硬币放在碗里, 小李把一个硬币放在碗里,移动碗直到眼睛看不到 为止,保持头部不动,往碗里倒水, 为止,保持头部不动,往碗里倒水,倒到一定程度 小李又重新看到硬币。 时,小李又重新看到硬币。 现象。 (1)这种现象是光的 折射 现象。 ) (2)小李用作图方法说明结论正确的是( B ) )小李用作图方法说明结论正确的是( (3)如果用鱼叉去叉水中的鱼,应叉看到鱼的 )如果用鱼叉去叉水中的鱼, 上方” 下方” 下方 (填“上方”或“下方”)。
(06苏州 在研究平面镜成像特点的实验中 在 苏州)在研究平面镜成像特点的实验中 苏州 在研究平面镜成像特点的实验中,在 竖起的玻璃板前后各放一支蜡烛, 竖起的玻璃板前后各放一支蜡烛,对着玻璃 板既可看到前面蜡烛在玻璃板后所成的 同时又可看到放在玻璃板后的“ 像.同时又可看到放在玻璃板后的“蜡 烛”.下列说法中正确的是 D A.两者都是光的反射形成的像 . B.两者都是光的折射形成的像 . C.前者是光的折射形成的像,后者是光的 .前者是光的折射形成的像, 反射形成的像 D.前者是光的反射形成的像,后者是光的 .前者是光的反射形成的像, 折射形成的像
烧开水时冒的“白气” 烧开水时冒的“白气” 液化放热 冬天“冰冻” 冬天“冰冻”的衣服干了 升华吸热 冬天早晨看到草上的霜 凝华放热 熔化吸热 吃冰棒解热 夏天湿衣服晾干了 汽化吸热 钢水浇铸成火车轮 凝固放热
在松香、海波、冰、玻璃、铁、蜂蜡中属于晶体的是 在松香、海波、 玻璃、 海波、 海波、冰、 铁 __________。
空气
空气
空气
空气
水
水
水
水
A
BA
D
2000年8月,俄罗斯的库尔斯克号核潜水艇在巴 年 月 伦支海遇难, 伦支海遇难,探测专家用超声波可探测潜艇的确 切位置,超声波在海水中的波速为1450m/s,在 切位置,超声波在海水中的波速为 / , 潜艇正上方海面向下发出超声波, 潜艇正上方海面向下发出超声波,从超声波发出 直至接收到潜艇的回波经历的时间为0.2S,则潜 直至接收到潜艇的回波经历的时间为 , 艇沉没的实际深度约为多大? 艇沉没的实际深度约为多大?
鱼缸中只有一条小鱼,而眼睛可以从 鱼缸中只有一条小鱼,而眼睛可以从A 点观 察到两条鱼,一条鱼的位置变浅, 察到两条鱼,一条鱼的位置变浅,另一条鱼 变大。 变大。前者是 虚 像(填“实”或 右 );后者是由于鱼缸的 侧部分 “虚”);后者是由于鱼缸的 虚 (填“左”或“右”)等效凸透镜而形成的 像(填“实”或“虚)。
下列属于光的折射现象的是( 下列属于光的折射现象的是(
BD
)
A.人在湖边看到自己在水中的倒影 人在湖边看到自己在水中的倒影 B.人在河边看到水底的石头 人在河边看到水底的石头 C.司机从后视镜中看到汽车后面的景物 司机从后视镜中看到汽车后面的景物 D.奶奶戴着老花镜在看报纸 奶奶戴着老花镜在看报纸
某物体做匀速直线运动,由速度公式 某物体做匀速直线运动,由速度公式v=S/t 可知物体的( 可知物体的( )
C
A.速度与路程成正比 速度与路程成正比 B.速度与时间成反比 速度与时间成反比 C.路程和时间成正比 路程和时间成正比 D.路程和时间成反比 路程和时间成反比
声音在空气中传播时, 声音在空气中传播时,下列叙述中正 确的是( 确的是( D ) A.声音越强,声速越大 .声音越强, B. 声音越高,声速越大 声音越高, C.振幅越大,声速越大 .振幅越大, D. 声速的大小与声音本身无关
图6
在“研究凸透镜成像条件”的实验中,凸透镜的焦距 研究凸透镜成像条件”的实验中, 所示.回 为10cm;某同学做此实验时得到的像如图 所示 回 ;某同学做此实验时得到的像如图12所示 答下列问题: 答下列问题: (1)图中所观察到的像是倒立、放大的 实 像; )图中所观察到的像是倒立、 (2)从图中的现象可知蜡烛到凸透镜的距离的范围 ) 大于10cm小于 小于20cm 是 大于 ; 小于 (3)利用凸透镜的这一成像原理可制成 投影仪 ; ) (4)在如图的情况下,若把蜡烛与透镜的距离再增大 )在如图的情况下, 10cm,则增大后所成的像图 ,则增大后所成的像图12 是 倒 立 缩小 实 像. 的
市公交公司为了保证乘客上下车的安全, 市公交公司为了保证乘客上下车的安全, 在无人售票车上安装了“车载电视监控器” 在无人售票车上安装了“车载电视监控器” 如图所实施该装置的光学系统, 如图所实施该装置的光学系统,图中摄像 头的工作原理相当于_________镜成 头的工作原理相当于 凸透 镜成 实 ________像(选填“实”或“虚” ) 像 选填“
经常提到的: 经常提到的:①小孔成像 ②平面镜成像 ③幻灯机银幕上成的像 ④放大镜中正立的像 其中 属于实像的有: 属于实像的有: ①③ 属于虚像的有: 属于虚像的有: ②④ 反射而成像的有: 反射而成像的有:② 折射而成像的有: 折射而成像的有:③④
如图所示是“研究凸透镜成像规律” 如图所示是“研究凸透镜成像规律”的实验装置 放好仪器,点燃蜡烛, 图,放好仪器,点燃蜡烛,调整 凸透镜 和 光屏 的高度,使它们的中心跟烛焰的中心大致 的高度, 在同一高度, 在同一高度,这样做的目的 是 使像成在光屏的中央 .实验中发现蜡烛放在 A 点时, 点时,它的像成在 2F′点;放在 点 B 点时,它的像成在 点以外;放在 点时,它的像成在2F′点以外 点以外; C 点时成正立放大的虚像。 点时成正立放大的虚像。
图12
在同一平面上时。 (1)如图甲,当E、F在同一平面上时。让入射光 )如图甲, 、 在同一平面上时 沿纸板E射向镜面 线AO沿纸板 射向镜面,在F上可看到反射光线 沿纸板 射向镜面, 上可看到反射光线 OB,测出入射角和反射角的大小;改变入射光线 ,测出入射角和反射角的大小; 的方向,再观测几组入射角和反射角, 的方向,再观测几组入射角和反射角,这样做的 目的是为了比较 反射角和入射角的大小 。 若将AO向ON靠近,则OB 靠近, 若将 向 靠近 选填“靠近” (选填“靠近”或“远 靠近 离”ON。 。 为轴线, (2)如图乙,以法线 )如图乙,以法线ON为轴线,把纸板 向后缓 为轴线 把纸板F向后缓 探究反射光线、入射光线、 探究反射光线、入射光线 慢旋转, 慢旋转,这样做的目的是为 、法线是否在同一平面内 了 。 (3)本实验得出的结 ) 是 。
(06南昌 下列有关光的现象中,正确的说法 南昌)下列有关光的现象中 南昌 下列有关光的现象中, 是( A) A.阳光下,微风吹拂的河面,波光粼粼, .阳光下,微风吹拂的河面,波光粼粼, 这里蕴含着光的反射现象 B.汽车在夜间行驶时,应打开驾驶室里的 .汽车在夜间行驶时, 电灯 C.人在照镜子时,总是靠近镜子去看,其 .人在照镜子时,总是靠近镜子去看, 原因是靠近时, 原因是靠近时,平面镜所成的像会变大 D.在暗室里,为了能从镜子中看清自己的 .在暗室里, 脸部, 脸部,应把手电筒正对镜子照射
图7
在做“研究平面镜成像特点” 在做“研究平面镜成像特点” 的实验时 (1)李明在玻璃板的前面放一支点燃的蜡烛 还要在 李明在玻璃板的前面放一支点燃的蜡烛A,还要在 李明在玻璃板的前面放一支点燃的蜡烛 玻璃板的后面放一支没有点燃的蜡烛B,对蜡烛A 玻璃板的后面放一支没有点燃的蜡烛 ,对蜡烛 和B的要求是 完全相同 ,这是为 的要求是 了 比较像与物的大小 。 (2)在寻找蜡烛像的位置时,眼睛应该在 镜前 观 在寻找蜡烛像的位置时, 在寻找蜡烛像的位置时 小明无论怎样调节后面的蜡烛, 察。小明无论怎样调节后面的蜡烛,都不能与蜡烛 的像重合, 的像重合,请你推测可能的原因是玻璃板没有竖直摆放 。 (3)张红用跳棋代替点燃的蜡烛进行实验,但看不清 张红用跳棋代替点燃的蜡烛进行实验, 张红用跳棋代替点燃的蜡烛进行实验 跳棋的像。 跳棋的像。请你帮她想个办法看清跳棋的 像: 用手电筒照亮镜前的旗子 。 (4)李明要验证平面镜所成的像是虚像,进一步 )李明要验证平面镜所成的像是虚像, 的操作是 将白纸放在像的位置,直接观察白纸上能否 将白纸放在像的位置, 接受到像
解: 1 1 s = vt = × 1450m / s × 0.2 s = 145m 2 2
人们常说的两句话: 一叶障目, 人们常说的两句话:“一叶障目,不见 泰山” 捞不到的水中月, 泰山”和“捞不到的水中月,摘不到的 镜中花” 镜中花”,前后两句话主要涉及的光学 知识分别是 光的直线传播 和 光的反射 。
2009年元旦期间,朵朵礼花把天空染得五颜 年元旦期间, 年元旦期间 六色, 六色,小明在观看礼花时总是在看到烟花绽 放后才听到爆炸声, 放后才听到爆炸声,这是因为 光速比声速快 ______________________;小明感觉在庭 ; 院里燃放鞭炮比在野外燃放鞭炮时的响度明 显变大, 显变大,这是因为在庭院里声波经过多次 反射 __________造成的。 造成的。 造成的
1.下面几种说法,是对还是错 .下面几种说法, (1)同一种物质处于哪种状态与该物质此时 同一种物质处于哪种状态与该物质此时 的温度有关. 的温度有关. √ (2)晶体熔化时的温度叫做熔点. 晶体熔化时的温度叫做熔点. 晶体熔化时的温度叫做熔点