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一个平面截一球得到直径为6的圆面，球心到这个圆面的距离为4，则这个球的体积为$（ ）
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高一下学期数学《》真题及答案
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一平面截一球得到直径为2cm的圆面球心到这个平面的距离是2cm则该球的体积是
12π cm
3
36π cm
3
64
π cm
3
108π cm
3
给出下列说法①球的半径是球面上任意一点与球心的连线段②球的直径是球面上任意两点的连线段③用一个平面
一个与球心距离为2的平面截球所得的圆面面积为则球的表面积为.
用一个平面去截一个球截面是一个圆面.
用一个平面去截一个几何体得到的截面是圆面这个几何体不可能是
圆锥
圆柱
球
棱柱
[2012·辽宁部分重点中学联考]棱长为1的正方体和它的外接球被一个平面所截截面是一个圆及其内接正三
若一个球的表面积为现用两个平行平面去截这个球面两个截面圆的半径为.则两截面间的距离为________
已知平面α截一球面得圆M过圆M的圆心的平面β与平面α所成二面角的大小为60°平面β截该球面得圆N若
2
4
已知球心到球的一个截面的距离为5截面圆的半径为12则球的半径为.
已知球的半径为4球面被互相垂直的两个平面所截得到的两个圆的公共弦长为2．若球心到这两个平面的距离相
4
6
8
10
半径为5的球被一平面所截若截面圆的面积为16π则球心到截面的距离为
4
3
2.5
2
用平面α截半径为R.的球如果球心到平面α的距离为那么截得小圆的面积与球的表面积的比值为.
一平面截一球得到直径是6cm的圆面球心到这个平面的距离是4cm则该球的体积是.
用一个平面截半径为25cm的球截面面积是225πcm2则球心到截面的距离为____cm.
用一个平面去截体积为π的球截面圆的面积为3π则球心到截面的距离是
1
2
已知平面α截一球面得圆M过圆心M且与α成60°二面角的平面卢截该球面得圆N若该球面的半径为4圆M的面
7π
9π
11π
13π
一个棱长为2的正八面体的六个顶点都在一个球面上则球心到正八面体的一个侧面的距离等于.
用一个平面截其球体得到直径为4的圆且球心到这个平面的距离是2则该球的表面积是____________
一平面截一球得到直径是6cm的圆面球心到圆面的距离是4cm则该球的体积是
已知球的半径为4球面被互相垂直的两个平面所截得到的两个圆的公共弦长为2．若球心到这两个平面的距离相
4
6
8
10
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10分假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加在缺词处加一个漏字符号∧并在其下面写出该加的词. 删除把多余的词用斜线\划掉. 修改在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改均仅限一词2.只允许修改10处多者从第11处起不计分. TheotherdayTomwasridingalongthestreetwhenacarranfastlytowardshim.Heturnedleftquicklyanditwastoolate.Thecarhithimselfandhefelloffhisbike.Thedriverofthecarwassofrighteningthatheranawayasfasthecould.SoonthedriverisoutofsightleavingTomhelplessonthespot.Fortunateawomanhappenedtoseeingitandrememberedthenumberofthecar.Shecalledapolicemanandtoldhimwhenhadhappened.Atthelastthedriverwascaughtandpunishedforhiswrongdoing.
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已知实数xy满足xcosα+ysinα＝1则的最小值为．
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极地卫星的运行轨道经过地球的南北两极正上方轨道可视为圆轨道．如图所示某时刻某极地卫星在地球北纬45°A点的正上方按图示方向运行经过12h后再次出现在A点的正上方地球自转周期为24h．则下列说法正确的是
氨气和氯气是重要的工业原料某兴趣小组设计了相关实验探究它们的某些性质．实验一用氨气认识喷泉实验的原理并测定电离平衡常数KNH3•H2O 1检査图1的装置Ⅰ的气密性的方法是． 2喷泉实验结束后发现三颈烧瓶未充满水假如装置的气密性良好原因是．用填仪器名称量取25.00mL喷泉实验后的氨水至锥形瓶中用0.0500mol/L盐酸滴定测定氨水的浓度滴定曲线如图2所示．下列关于该滴定实验的说法中正确的是选填字母． A．当pH＝7.0时氨水与盐酸恰好中和B．选择酚酞作为指示剂测定结果偏低 C．酸式滴定管未用盐酸润洗会导致测定结果偏低D．当pH＝11.0时KNH3•H2O约为2.2×10﹣5 实验二拟用图3装置设计实验来探究纯净干燥的氯气与氨气的反应． 3A中所发生反应的化学方程式为． 4图3中的装置连接顺序为A→→→→→用大写字母表示．若按照正确顺序连接实验装置后整套实验装置存在的主要缺点是． 5写出F装置中的反应的一种工业用途． 6反应完成后F装罝中底部有固体物质生成．请利用该固体物质设计一个实验方案证明NH3•H2O为弱碱其余实验用品自选．
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短周期主族元素WXYZ的原子序数依次增大WZ同主族．WXYZ四种元素形成化合物Q25℃时Q溶液的pH＞7．下列说法正确的是
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如图所示水平放置的密闭导热气缸通过一段不计体积的导管和上端开口玻璃管相连气缸被一不计厚度的隔热轻活塞隔成体积相同的两部分气体气体压强均等于大气压强P0长度均为L＝10cm上部分气缸中接有一段体积不计的电阻丝玻璃管内装有一段长为h＝40cm的水银导管处阀门关闭．已知气缸横截面积为S玻璃管横截面积为外界温度为T＝27°CP0＝75cmHg封闭气体可视为理想气体．求 ①打开阀门求稳定后玻璃管内水银柱长度h' ②给活塞上部分气体用电阻丝加热直至水银柱回到初始液面求此时上部分气体的温度T'．
已知函数fx＝2sinxsinx++cos2x﹣sin2x 1求函数fx的单调递减区间 2若将函数fx图象上所有点的横坐标缩短为原来的倍纵坐标不变然后再向右平移φφ＞0个单位长度所得函数的图象关于y轴对称．求φ的最小值
已知 下列说法不正确的是
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一物体的运动图象如图所示横纵截距分别为n和m在图象所示的运动过程中下列说法正确的是
在某一次数学测验中从全校抽出n名同学并记录其测验成绩满分100分进行统计•按照[50.60[6070[7080[8090[90100]的分组作出频率分布直方图并作出分数的茎叶图图中仅列出了分数在[5060[90100]的数据． 1求n和频率分布直方图中的xy的值 2在抽出的名学生中从分数在80分以上含80分的同学中随机选取2名求所抽取的2名同学至少有一名的成绩在[90100]内的概率．
如图所示在平面直角坐标系xoy的一二象限内分别存在以虚线OM为边界的匀强电场和匀强磁场．匀强电场方向沿y轴负方向匀强磁场方向垂直于xoy平面向里虚线OM与x轴负方向成45°角．一质量为m电荷量为+q的带电粒子从坐标原点O处以速度v0沿x轴正方向运动粒子每次到x轴将反弹每次反弹水平分速度不变竖直分速度大小均减为反弹前的倍方向相反．电场强度大小为磁感应强度大小为求 不计粒子重力题中各物理量单位均为国际单位计算结果可用分式表示 1带电粒子在磁场中运动的时间 2带电粒子最后一次经过OM时的位置坐标 3带电粒子从最后一次经过OM时开始沿电场方向运动的总路程．
6分Ifyou'reonthehuntforsomethingnewandinterestingtoreadyouhaveplentyofplacestogo.Thisweekwe'relookingatfourofthebestbookrecommendationsitesservicesorgroupsbasedonyournominations提名. GoodReads GoodReadsismorethanjustabookrecommendationsitealthoughitexcelsathelpingyoufindnewbookstoreadbasedontheonesyouenjoy.Youcanbuildavirtualshelfofbooksyouownorhavealreadyreadshareyourprogresswiththebooksyou'recurrentlyreadingratethebooksyou'vereadleavereviewsandconnectwithotherreaders. BookBub WhileBookBubisn'tstrictlyabookrecommendationserviceitdoesbringyousuper﹣low﹣costbooksbasedonyourinterestseveryday.TheserviceisfreeandwhenyousignupyoutellBookBubwhatkindsofbooksyouliketoread.Fromthereyou'llgetanemailfromBookBubeverydaywithbookdealsforthatday.Whenwesaydealwemeanit﹣manyofBookBub'stitlesarefreeentirely$0.99orjustacoupleofbucks. LibraryThing LibraryThinghasbeenaroundforalongtimeandisstillagreatuser﹣poweredbookratingsreviewandrecommendationsite.Theservicecallsitselftheworld'slargestbookclubandthat'salotliketheoverallfeel.Onceyousignupyou'llbeencouragedtostartaddingbooksyou'vereadandleavereviewsforthem.BehinditsbookratingsandreviewsthoughLibraryThingisapowerfultooltocatalogandorganizeyourentirebookcollection. Olmenta Ifyou'renotinterestedinregisteringforaccountsaddingyourownbooksoranyofthathassle麻烦Olmentacansuggestsomesolidtitlestoyoubasedongeneralpopularityandthecitationofthepeoplebehindthesite.It'sasimplelistofbookcoversthattheservicethinksyoushouldreadandafewgenresyoucanclickonifyou'relookingforsomethingspecificlikebusinessfictionchildren'stheatrepoetryornonfictionamongothers. 1Whichofthefollowingtwobookrecommendationsitesaskyoutorateandleavereviews? A.GoodreadsandBookBub B.BookBubandLibraryThing C.LibraryThingandOlmenta D.GoodreadsandLibraryThing 2Whichbookrecommendationsitecanhelpyougetsuper﹣low﹣costbooks? A.GoodReads B.BookBub C.LibraryThing D.Olmenta 3IfyouturntoOlmentayou. A.needtopaymore B.needtoaddyourownbook C.don'tneedtosignup D.don'tneedtolookforsomethingspecific
8分Father'sDayiscelebratedtodayin75countriesaroundtheworld.Inmypersonalworldit'sadayIliketothinkofmyfather'sfather. Ilearnedalotinmylaterlifefrommydad.ButIlearnedsomethingelseasakidnotevenyetinschoolfrommygrandfather.Ilearnedtobecurious.Littlethingsfathersandgrandfathersdocanchangethelifeofachildforever.InmycasethischangecamefromnecessityMymomneededsomeonetolookafterlittleAllenbarely4yearsoldduringtheschoolday.MygrandmothervolunteeredandmygrandfathercameupwithawayIcouldbewatchedwhileheworkedinhisclockmaker'sshop. HeseatedmeonachaireverydaywhileIwasthererightinfrontofhisbigworkbench.Hetoldmestories.Hehadagreatsenseofhumorandafunnywayofmakingabuh﹣buh﹣buhsoundwhenhesensedmyattentionwasweakeningandheencouragedmetoaskquestionsaboutanythinghewasdoing. NaturallyIwasusuallyaskingquestionsaboutclocks﹣﹣whatmadethehandsmovewhatthependulum钟摆didwhyyouhadtostopwindingjustbeforetheweighthitthestop.SometimesIjustaskedaboutwhichshinypartswentwhere. Mostofallheshowedmehowclocksworked.HetreatedmeasifIwereasortofsmallgrown﹣up.HenevertalkeddowntomenevertoldmeIwastooyoungtounderstand. AndsomygrandfathergrantedmetwothingsAloveofclocksandaneverlastingcuriosity. AsajournalistIturnedthatfascinationintoexplanationsofwhycomputersandsoftwaredowhattheydo﹣﹣andperhapsevenmoreimportantlywhytheyfailatthattask.Ihaven'tbeenafraidofopeninguptheinnardsandlookingforwhatiswrongwiththecomputer. 1Theauthorloveshisgrandfatherbecause. A.helearnedalotfromhim B.hetoldsomestoriestomakehimjoyful C.hewasbroughtupbyhisgrandfather D.hisfatherseldompaidattentiontohim 2Whilestayingwithhisgrandfathertheauthor. A.wastiredofthenoisesintheshop B.wasattractedbyhisgrandfather C.wasforcedtositstillonthechair D.wasalwaysaskingstrangequestions 3Whatistheauthor'sgrandfatherlikeinthepassage? A.Gentleandenthusiastic. B.Kindandexperienced. C.Activeanddependable. D.Patientandresponsible. 4Weknowaccordingtothepassagethattheauthor. A.doesn'tlivewithhisfatheranylonger B.becamemoreinterestedincomputersthanclocks C.wasinterestedinfindingoutaboutsomething D.oncebrokealotofclocks
8分Scientistsarepreparingtolaunchtheworld'sfirstmachinetocleanuptheplanet'slargestmassofoceanplastic.Theexpertsbelievethemachineshouldbeabletocollecthalfofthedetritusinthepatch﹣about40000metrictons﹣withinfiveyears.Inthepastfewweekstheyhavebeenbusyweldingtogethergianttubesthatwillsitonthesurfaceoftheseaandformtheskeletonofthemachinecreatingthelargestfloatingbarrierevermade. ThesystemoriginallydreamedupbyMr.SlatwillbeshippedoutthissummertotheGreatPacificGarbagePatchbetweenHawaiiandCaliforniaandwhichcontainsanestimated1.8trillionpiecesofplastic.Itwillbethefirsteverattempttotacklethepatchsinceitwasdiscoveredin1997. Mr.Slatwas16andstillatschoolwhenhewasdivinginGreeceandfirstsawforhimselftheamountofplasticpollutingthesea.Thereweremorebagsthanfishdownthereherecalls.TwoyearslaterhecameupwithasolutionquituniversityaftersixmonthsandsetupTheOceanCleanupasacompany.Mr.Slat23saysthefirstplastictoarriveonshorewillbeamajormilestone.WeasahumanitycreatedthisproblemsoIthinkit'sourresponsibilityalsotohelpsolveithesaid. TheGreatPacificGarbagePatchGPGPspans617763sqmiles﹣morethantwicethesizeofFranceandcontainsatleast79000tonsofplasticresearchfoundlastmonth.Mostofitismadeupofghostgear﹣partsofabandonedandlostfishinggearsuchasnetsandropes﹣oftenfromillegalfishingvessels. Ghostgearkillsmorethan100000whalesdolphinsandsealseachyearaccordingtoscientificsurveys.Seabirdsandothermarinelifeareincreasinglybeingfounddeadwithstomachsfullofsmallpiecesofplastic.Creatureseatplasticdiscardedintheseathinkingit'sfoodbutthenstarvetodeathbecausetheyarenotfeedingproperly.Othersaretrappedanddieofstarvationorarestrangledorsuffocatedbyghostgear. 1Whatdoestheunderlinedwordinthefirstparagraphprobablymean? A.waste. B.ocean. C.system. D.machine. 2AccordingtothepassagemostoftheGarbageinPacificismadeupof. A.fishingvessels B.dolphinsandseals C.gianttubes D.abandonedfishinggear 3WhydosomecreaturesinTheGreatPacificGarbagePatchdieofstarvation? A.becausetheywerekilledbyGhostgear. B.becausetheyweresuffocatedbyghostgear. C.becausetheydidn'tlikeeatingplastic. D.becausetheyarenotfeedingproperly. 4WhatisthemainideaofthePassage? A.newsaboutthefirstmachinetocleanupoceanplastic. B.reportaboutthedeathofmarinelife C.informationaboutoceanplastic. D.thereasonforinventingamachine.
如图所示某种透明材料制成的直角三棱镜ABC折射率n＝∠A＝在与BC边相距为d的位置放置一平行于BC边的竖直光屏现有一细光束射到棱镜AB面上的P点入射光线与AB面垂直线CP的夹角为iPB的长度为d试求 ①当i＝且光束从BC面出射时光屏上的亮斑与P点间的竖直距离 ②当光束不从BC面出射时i的正弦值应满足的条件．
已知向量是单位向量＝34且在方向上的投影为﹣則|2﹣|＝
10分Livingabroadwillmakeyouadifferentpersonanditwillchangeyouforeverinagoodway.Ilivedabroadformorethanfouryears.1.Herearethemostimportantfourreasonswhyyoushouldstudyabroadandmakethemostofyourstayabroad. Improveyourjobchances.2.HRmanagersvalueinternationalexperiencehighlyascandidateswithexperiencesofstudyingabroadareconsideredtobeadaptableindependentproblem﹣solvingandopen. 3.Gettingoutofyourhomeiscertainlynoteasybutitwillhelpyougrow.Gooutthereandexperiencetheworld.Seeitasanadventurethatyouwilltellyourgrandkidsabout.Sometimesyouhavetopushyourselfandthenyouwillberewardedwiththisawesomefeelingofaccomplishment. Createamemoryofalifetime.Spendingtimeabroadwillbeanadventureandthosememorieswilllastforalifetime.Iknowalotofpeoplethatoncelivedabroadandnoneofthemregretsthetimetheyspentabroad.Yestherewillbedifficulttimes.Whenyoudon'tunderstandthepeoplearoundyoueverythingisforeignandnothingmakessense.Everydaytasksseemlikeamajorproblem.4. Becomeindependent.Livinginaforeigncountryallbyyourselfwillsurelymakeyouindependent.Youareforcedtomakedecisionsbyyourselfasyoudon'thaveotherchoices.5.Showthemthattheywereallsowrongaboutyourbeingamama'sboyorgirl!Itwillfeelgreat! A.Getawayfromhome. B.Improveyourlanguageskills. C.Itwasandstillisthebiggestadventureinmylife. D.Showyourselfyourparentsandfriendsthatyoucandoit. E.Differentcultureshavedifferentvaluestraditionsandcustoms. F.ButIcantellyoufrommyexperiencethatitisdefinitelyworthit. G.Experienceabroadwillgiveyouanadvantageoverotherapplicantsinthejobmarket.
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