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在如图所示宽度范围内，用电场强度为E的匀强电场可使初速度是v0的某种正粒子偏转θ角．在同样宽度范围内，若改用方向垂直于纸面向外的匀强磁场，匀强磁场的磁感应强度为B，使该粒子穿过该区域，并使偏转角也为...
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高三下学期物理《》真题及答案
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如图所示一质量为m电量为+q的带电小球以v0的初速度射入水平方向的匀强电场中小球恰能在电场中做直线运
如图所示在宽度为L.的两虚线区域内存在匀强电场一质量为m带电量为+q的滑块可看成点电荷从距该区域为L
如图所示第二象限内充满了垂直纸面向外的匀强磁场磁感应强度为B.第一第四象限内充满了一匀强电场其方向如
如图所示长为L.＝0.5m倾角为θ＝37°的光滑绝缘斜面处于水平向右的匀强电场中一带电荷量为＋q质量
小球在
点的电势能大于在A.点的电势能 B.水平匀强电场的电场强度为
若电场强度加倍，小球运动的加速度大小为3 m/s2
若电场强度减半，小球运动到B.点时速度为初速度v0的一半
如图所示真空中存在空间范围足够大的方向水平向右的匀强电场在电场中一个质量为m带电量为q的粒子从O.点
如图所示在区域Ⅰ0≤x≤L和区域Ⅱ内分别存在匀强电场电场强度大小均为E.但方向不同.在区域Ⅰ内场强方
如图所示一个质量为m带电量为q的正离子从D点以某一初速度v0垂直进入匀强磁场.磁场方向垂直纸面向内磁
如图所示在虚线所示宽度范围内用场强为的匀强电场可使初速度是的某种正离子偏转角.在同样宽度范围内若改用
如图所示一带电粒子的质量为m带电量为+q以初速度v0从A点垂直射入匀强电场过一段时间后粒子到达B点速
如图所示在某一区域存在匀强电场方向竖直向下场强大小为E.有一正粒子以垂直电场的初速度v0从电场左边界
18分如图所示匀强电场分布在宽度为L.的区域内一个正离子以初速度垂直于电场方向射入场强为E.的匀强电
如图所示的区域中第三象限为垂直纸面向里的匀强磁场磁感应强度为B第一第四象限是一个电场强度大小未知的匀
如图所示的区域中左边为垂直纸面向里的匀强磁场磁感应强度为B.右边是一个电场强度大小未知的匀强电场其方
在如图所示宽度范围内用场强为E.的匀强电场可使初速度是v0的某种带正电粒子偏转θ角.在同样宽度范围内
电场强度E.与磁感应强度
之比
B. 电场强度E.与磁感应强度B.之比
粒子穿过电场和磁场的时间之比
粒子穿过电场和磁场的时间之比
如图所示一质量为m电量为＋q的带电小球以与水平方向成某一角度θ的初速度v0射入水平方向的匀强电场中小
如图所示的区域中左边为垂直纸面向里的匀强磁场磁感应强度为B右边是一个电场强度大小未知的匀强电场其方向
如图所示匀强电场分布在宽度为L.的区域内一个正离子以初速度垂直于电场方向射入场强为E.的匀强电场中穿
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如图所示一带电粒子以一定的初速度由P.点射入匀强电场入射方向与电场线垂直粒子从Q.点射出电场时其速度
如图所示在宽度为L.的两虚线区域内存在匀强电场一质量为m带电量为+q的滑块可看成点电荷从距该区域为L
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15分Peoplewhogotoaformalwesterndinnerpartyforthefirsttimemaybesurprisedbytablemannersinwesternculture.Knowingthemwillhelpyoumakeagood1印象.Havinggoodtablemannersmeansknowinghowtouseknifeandforkwhento2datoast干杯andhowtobehaveatthe3.Attableyoushouldtrytospeakquietlyand4salotbutnotlaughallthetime.Mostwesternerslike5drinksiftheydrivehome.Manyofthemdrinkwhiteorredwinewiththe6f.Whendrinkingtoone'shealthyou7ryourglassbuttheglassshouldnottouch.The8风俗oftoastinginsomepartsofChinaistofinishdrinkat9obutwesternersusuallytakeonlyasip.Butdorememberthattablemanners10overtimewehavetofollowthefashionoftheday.Ifyouarenotsurewhattodoyoucanfollowyourhosts.
在双缝干涉实验中用绿色激光照射在双缝上在缝后的屏幕上显示出干涉图样．若要增大干涉图样中两相邻亮条纹的间距可选用的方法是
如图质量为M的小船在静止水面上以速率v0向右匀速行驶一质量为m的救生员站在船尾相对小船静止．若救生员以相对水面速率v水平向左跃入水中则救生员跃出后小船的速率为
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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一下作文.文中共有10处语言错误每句中最多有两处.没出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.没出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. Aswintercomestherearemuchrainandsnowinmanypartsofourcountryincludingourcity.Itistoocoldthatanincreasingnumberofstudentscatchacold.Evenworsesomestudentsfelldownandhurtthembecausetheicyroads.Soweshouldprotectourselvesfromcoldweatherandtherearemanythingswhatareofhelp.Firstweshouldputupmoreclotheswhengoingoutside.Thentoremembernottorunorwalktoofastonslipperyroads.Luckilysomemeasureshavebeentakingtopreventusfromfallingdown.Forexamplesomematshavebeenplacedonthestepoftheteachingbuilding.Ihopeeveryoneissafeandhealth.
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如图有一辆汽车在一条水平的公路上向正西行驶汽车在A点测得公路北侧山顶D的仰角为30°汽车行驶300m后到达B点测得山顶D在北偏西30°方向上且仰角为45°则山的高度CD为
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如图所示．两根水平放置且相互平行的长直导线分别通有方向相反的电流l1与l2．且I1＞I2与两根导线垂直的同一平面内有abcd四点abc在两根导线的水平连线上且间距相等b是两根导线连线的中点abcd连线与两根导线连线垂直．则
函数y＝x2+ln|x|的图象大致为
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如图所示两间距为d的平行光滑导轨由固定在同一水平面上的导轨CD﹣C′D′和竖直平面内半径为r的圆弧导轨AC﹣A′C′组成水平导轨与圆弧导轨相切左端接一阻值为R的电阻不计导轨电阻水平导轨处于磁感应强度大小为B方向竖直向上的匀强磁场中其他地方无磁场．导体棒甲静止于CC′处导体棒乙从AA′处由静止释放沿圆弧导轨运动与导体棒甲相碰后粘合在一起向左滑行一段距离后停下．已知两棒质量均为m电阻均为R始终与导轨垂直且接触良好重力加速度大小为g求 1两棒粘合前瞬间棒乙对每个圆弧导轨底端的压力大小为N 2两棒在磁场中运动的过程中电路中产生的焦耳热Q 3两棒粘合后受到的最大安培力Fm．
WilkieCollinswasborninLondonin1824andhisfirstnovel﹣﹣ahistoricalromancecalledAnatonia﹣﹣waspublishedwhenhewas26.ShortlyafterthishemetCharlesDickensandtheyformedaclosefriendshipthatlastedfortenyearsandinfluencedbothmen'swriting.Collinswentontopublish25novelsaswellasmanyshortstoriesplaysandworksofnon﹣fiction.HoweverheismostwellknownforthetwomysterynovelsTheWomaninWhiteandTheMoonstone. CollinspublishedbothmysteriesasserialsinAlltheYearRound.Whenitappearedinthemagazinein1860TheWomaninWhitewassopopularthatitbecamethesubjectofasongandaplay.Iteveninfluencedfashionandmanywomenstartedtodressinwhite.EightyearslaterTheMoonstonewaspublishedandearnedCollinsthetitlethefatherofthemodernEnglishdetectivenovel.TSElliotanotherfamouswritersaidthatTheMoonstonewasthefirstandgreatestofEnglishdetectivenovelsanditisstilladmiredbymoderncrimewriterstoday. AnauthorofmanymysteriesDorothyLSayersconsideredTheMoonstonetobeprobablythefinestdetectivestoryeverwrittenandmanypeopleagreewithher.Thereareseveralreasonswhytheythinkso.OneisthatCollinsusesdifferentcharacterstotelleachsectionofthestory.Thecharactershaveverydifferentpersonalitiesandvoiceswhichareinterestingandoftenamusing.Therearealsoseveralfeaturesoftheplotwhichstartedtrendsinmysterywriting.Forexamplemanydetectivestoriesaresetinacountryhousewherethetheftmusthavebeencommittedbyoneofthepeopleinthehouse.Thecharacterofafamousdetectivewithanunusualappearanceandhabitsoccursinmanybooksandaninnocentpersonisoftenundersuspicionatfirst.Anumberofmodernfilmshavealsousedtheideaofacursedjewelstolenfromareligiousstatue.AndofcourseinTheMoonstoneandmostothergoodmysterynovelsthepersonwhoatfirstseemstheleastlikelytobethecriminalturnsouttobeguilty. 25.Anatoniawaspublishedin. A.1824B.1850C.1860D.1868 26.AlltheYearRoundwasatitleof. A.oneofWilkieCollins'books B.oneofCharlesDickens'books C.astoryofamagazine D.amagazine 27.CollinsisknownasthefatherofthemodernEnglishdetectivenovelbecause. A.hewasolderthantheotherdetectivestorywriters. B.hissonwasalsoafamousdetectivestorywriter. C.manyaspectsofhiswritingarecopiedbyotherdetectivestorywriters. D.theMoonstoneisthemostpopulardetectivestory.
6分 FrancesStevensReeseWooldlandTrailGuide TheWoodlandTrailwasopenedtothepubliconOctober211997.Boscobel'sBoardofDirectorsadoptedaformaldecisionofnamingtheWoodlandTrailinhonorofformerBoscobelboardmemberFancesStevensReese1917﹣2003oneyearafterhisdeath. Thetrail小径isapproximately10milesinlengthleadingdowntoConstitutionForest.WhentheWestPointGlassFactorywasoperatingduringtheCivilWartreesformilesaroundwereclearedtoprovidefirewood.Walkingoutoftheforestyouwillfindalargemassofnativehardrockaboutthreebillionyearsold. Throughoutthiscountrypathyouwillfindpictureboardsidentifyingbirdsandplantslocaltothisregion.Youwillalsofindsignswithhistoricandenvironmentalinformationwrittenbyareaspecialists. Whenyoutakeawalkthroughthisundiscoveredforestlandpleasebeaconsiderateguest. 〇BeforewalkingthetrailpleasepurchaseapassintheCarriageHouse.Planaheadsoyouwillbebackbyclosingtime. 〇Followthetrailmarkersandremainonthetrail.Besidesprotectingthefragileforestecosystemyouwillreducetheriskofpoisonplantsandsnakes. 〇Leaverocksplantsanimalsandartworkswhereyouseethemsothatthepersonbehindyoucanhavethesameexperience. 〇Carryoutwhateveryoucarryinbecausetherearenorubbishcontainersonthetrail.Ifyouhappentoseeapieceoflitterbeagoodguestandpickitup. 1WhenwasthetrailnamedtohonorFrancesStevensReese A.In1997. B.In1917. C.In2003. D.In2004. 2Whatcanyouseealongthetrail A.Anoldbattlefield. B.Aglassfactory. C.Informationsigns. D.Rockhouses. 3Whatshouldyoudoasathoughtfulvisitor A.Leavethewildlifeundisturbed. B.Throwtherubbishintothedustbins. C.MakereservationsintheCarriageHouse. D.ProtectthemarkersoftheWoodlandTrail.
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如图所示一棱镜的截面为直角三角形ABC∠A＝30°斜边AB＝8cm棱镜材料的折射率n＝在此截面所在的平面内一条光线以60°的入射角从AC边的中点M射入棱镜求出射点到B点的距离不考虑光线沿原路返回的情况
计算sin+tan＝
图甲所示的理想变压器原副线圈的匝数分别为100和20现在变压器原线圈两端接入按图乙所示的规律变化的正弦交变电压则
当前电磁炉已走进千家万户电磁炉是利用电流通过线圈产生的磁场该磁场会使锅底产生涡流自行发热从而加热锅内的食物下列材料中可用来制作电磁炉的锅的是
已知向量＝snx﹣2cosx＝2cosxcosx函数fx＝•+1x∈R． 1求函数fx的单调递增区间 2在△ABC中内角ABC所对边的长分别是abc若fA＝2C＝c＝2求△ABC的面积S△ABC．
8分ChoosingtoforgetsomethingmighttakemorementaleffortthantryingtorememberitresearchersatTheUniversityofTexasatAustindiscoveredthroughneuroimaging神经成像. ThesefindingspublishedintheJournalofNeurosciencesuggestthatinordertoforgetanunwantedexperiencemoreattentionshouldbefocusedonit.Thissurprisingresultcontinuespreviousresearchonintentionalforgettingwhichfocusedonreducingattentiontotheunwantedinformationthroughredirectingattentionawayfromunwantedexperiencesorholdingbackthememory'sretrievals恢复. WemaywanttogetridofmemoriesthatcausenonadaptiveresponsessuchasupsettingmemoriessothatwecanrespondtonewexperiencesinmoreadaptivewayssaidJarrodLewis﹣Peacockthestudy'sseniorauthorandanassistantprofessorofpsychologyatUTAustin.Decadesofresearchhasshownthatwehavetheabilitytovoluntarilyforgetsomethingbuthowourbrainsdothatisstillbeingquestioned.Oncewecanfigureouthowmemoriesareweakenedanddesignwaystocontrolthiswecandesigntreatmenttohelppeopleridthemselvesofunwantedmemories. Usingneuroimagingtotrackpatternsofbrainactivitytheresearchersshowedagroupofhealthyadultsimagesofscenesandfacesinstructingthemtoeitherrememberorforgeteachimage.Theirfindingsnotonlyconfirmedthathumanshavetheabilitytocontrolwhattheyforgetbutthatsuccessfulintentionalforgettingrequiredmoderate适中的levelsofbrainactivityinthesesensoryandperceptualareas感官区域﹣moreactivitythanwhatwasrequiredtoremember. Amoderatelevelofbrainactivityiscriticaltothisforgettingmechanism.Toostronganditwillstrengthenthememorytooweakandyouwon'tchangeitsaidTracyWangleadauthorofthestudyandapsychologypostdoctoralfellowatUTAustin.Importantlyit'stheintentiontoforgetthatincreasestheactivationofthememoryandwhenthisactivationhitsthe‘moderatelevel'sweetspotthat'swhenitleadstolaterforgettingofthatexperience.Theresearchersalsofoundthatparticipantsweremorelikelytoforgetscenesthanfaceswhichcancarrymuchmoreemotionalinformationtheresearcherssaid. We'relearninghowthesemechanismsinourbrainrespondtodifferenttypesofinformationanditwilltakealotoffurtherresearchandreplication重复ofthisworkbeforeweunderstandhowtocontrolourabilitytoforgetsaidLewis﹣Peacockwhohasbegunanewstudyusingneurofeedbacktotrackhowmuchattentionisgiventocertaintypesofmemories. Thiswillmakewayforfuturestudiesonhowweprocessandhopefullygetridofthosereallystrongstickyemotionalmemorieswhichcanhaveapowerfuleffectonourhealthandwell﹣beingLewis﹣Peacocksaid. 1Previousstudiesonintentionalforgettingresearched. A.thepatternofbrainactivity B.theprocessofrecoveringamemory C.thewaytoreduceattentiontounwantedinformation D.theamountofattentionrequiredbyintentionalforgetting 2AccordingtoTracyWangforgettingispossiblewhen. A.peoplerespondtonewexperiencesinanadaptiveway B.theactivationofthememoryreachesacertainlevel C.peoplehavethestrongestintentiontoforget D.theinformationinvolvesmoreemotion 3Lewiscontinueshisstudytofindout. A.howtocontrolpeople'sabilitytoforget B.wheretoapplythefindingsofhisteam'slateststudy C.whateffectsupsettingmemorieshaveonpeople'shealth D.ifdifferenttypesofinformationrequiresdifferentlevelsofattention 4Whatisthebesttitleofthearticle A.Wheredoesforgettingtakeplace B.Howdoesattentionaffectmemory C.Forgettingusesmorebrainpowerthanremembering D.Forgettingisfarmoredifficultthanweonceimagined
如图所示倾角θ＝37°的粗糙斜面固定于水平地面上一木块从斜面底蟈以某一初速度滑上斜面一段时间后返回到斜面底端木块在上滑和下滑过程中加速度的大小的比值为2假设斜面足够长．取g＝10m/s2sin37°＝06cos37°＝0.8求 1木块与斜面间的动摩擦因数μ 2木块从斜面底端运动到最高点的过程中克服重力做的功与产生的热量的比值．
已知ab∈Rab≠0两圆x2+y2+2ax+a2﹣4＝0和x2+y2﹣4by﹣1+4b2＝0只有一条公切线则的最小值为
Dandelions蒲公英arecommonweedsthatgrowinmanyplacesaroundtheworld.Indifferent41dandelionstakedifferentshapes.Scientistshavelong42thatdifferenthabitatsledtothecreationof43speciesandthatdifferencesinformareactualproofofdifferentspecies.44accordingtoTuressonitisalsopossiblethata45speciestakesdifferentshapesdependentonthehabitatsit46in.TostudythisIhavelookedattwodandelionsgrowingindifferenthabitats.Theone47IwillcallDandelion1growsinagrassfieldthatliesinthe48.TheotherDandelionDandelion2growsintheshadoweg49thetreesorbehindashed.Thegrassfieldishotand50.Theshadowiscoolandwet.Sowhatarethe51betweenDandelion1and2?Dandelion1isdarkgreenandits52areshortandquitethick.Mostoftheleaveslie53onthesurroundinggrass.Theflowersareshort.Dandelion2ontheotherhandlooksverydifferently.Theleavesarelongand54greenMostleavesstandinaverticalposition.Theflowersalso55tall.Dandelion256strongandtall.Itisclearthatitgrowsverywellinthe57andthathasenough58andspacetogrowintoabigplant.Dandelion1ontheotherhandissmallanddark.Itseemsthatthe59inthegrasslandmakeitdifficultforthisdandeliontogrowintoabigplant.60theconditionsinthetwodifferenthabitatsresultindifferentshapesforthesedandelions.ForDandelion1thesunmakesthegrassfieldhotanddry.Inordertosavewateritgrowsshortandthickleaves.41.A.houses B.habitats C.parks D.countries42.A.disagreed B.provided C.believed D.calculated43.A.new B.good C.old D.bad44.A.However B.Therefore C.Thus D.Otherwise45.A.same B.different C.strange D.single46.A.plants B.works C.takes D.grows47.A.what B.which C.that D.when48.A.world B.mountain C.sun D.valley49.A.under B.over C.upon D.between50.A.humid B.wet C.soft D.dry51.A.similarities B.advantages C.differences D.disadvantages52.A.seeds B.leaves C.weeds D.woods53.A.flat B.apart C.dead D.logical54.A.dark B.bright C.artificial D.familiar55.A.lie B.break C.stand D.perform56.A.sounds B.smells C.feels D.looks57.A.swallow B.shallow C.shadow D.shape58.A.sunshine B.leaves C.honey D.water59.A.conditions B.occasions C.situations D.preparations60.A.Fortunately B.Obviously C.Consequently D.Accidentally
Manyscholarshipsrequirethatyouwriteanessayinordertobeconsideredfortheprizemoney.Howeverifyouarethesortofpersonthathasaheadachewheneveryouhavetocompleteawritingassignmentthismaynotbethebestnews.Luckilyforyouthereisnoreasontofearthescholarshipessay.Thefollowingtipscouldhelpyouconquerthisnot﹣so﹣easyaspectofthescholarshipapplicationprocess. Youshouldalwaysoutlineyouressays.Thisdoesnotjustapplytothescholarshipessayseither.Anoutlinehelpslendfocustoyourthoughtsandhelpsyoucreateapictureofthewholethattheessaywillbecome.Judgescannottostandwhenyourwritingislooselackscoherence连贯性orwhenyoufailtoconnectyourmainpointstogether.Theywanttoseethatyoucansupportyourargumentwellwithclearandbriefexamplesandthattheseexamplesdoinfactrelatetothetopicathand. Ifyouhaveachoiceinthetopicyougettowriteaboutalwaystrytoselectsomethingyouarepersonallyinterestedin.Don'twritewhatyouthinkthejudgeswanttohear.Thiswillonlyamountinanessaythatreadslikesomeoneelse'swhichisnotagreatwaytomakeyourselfstandout. Ifyoufeelboredwiththetopicthenyouressaywillbeboringaswell.Makesureyourideafollowaclearandalogicalpath.Thismeanstheyareconnectedwellandthetransitions过渡easilyflowfromoneideatothenext.Likewisetrytostayawayfromtheobviousorthesadstory.Yescollegewillbealife﹣changingexperiencebutcanyouthinkofaninterestingreasonwhythisisso?Andyesitisterriblethatyoulostafamilymemberatayoungagebutwhatdoesithavetodowithwinningthisscholarship?Judgescansmellsadstoriesfromamileawaysoonlypullattheheartstrings动人心弦ifyouhaveaproperreasonfordoingso. 32.Whenwritingascholarshipessayanoutlineisnecessarybecauseithelpsyou. A.focusonthedetailsoftheessay B.thinkmoreaboutthescholarship C.makeapictureofthewholeessay D.supportyourargumentwell 33.Youressaywillbeappreciatedbyjudgesifit. A.turnsouttobeloose B.isshortofcoherence C.isunabletoconnecttothemainpoints D.supportsyourargumentwithbriefexamples 34.Whatistheauthor'sopiniononchoosingthetopicforascholarshipessay? A.Theessayshouldincludetheobviousorthesadstory. B.Youmustkeepyourmindclearandlogical. C.Youhadbettertrytoputaninterestingstoryinit. D.Trytosayasmuchasyoucanaboutyourfamily. 35.Theintendedreadersofthepassageareprobably. A.collegestudents B.judgesincolleges C.essayreaders D.companyleaders.
假设人造卫星发射后在预定轨道上做匀速圆周运动它的周期为T引力常量为G．现要估算地球的质量则还只需知道
已知四面体ABCD中EF分别是ACBD的中点若AB＝2CD＝4EF与CD所成角的度数为30°则EF与AB所成角的度数为
已知等比数列{an}为递增数列a2a5＝32a3+a4＝12数列{bn}满足bn＝log2an． 1求数列{bn}的通项公式 2求数列{anbn}的前n项和Sn．
某同学利用图甲所示的实验装置做“研究匀变速直线运动”的实验． ①按住小车在小吊盘中放入适当质量的物块．释放小车小车由静止开始运动． ②按实验要求正确装上纸带．让小车靠近打点计时器按住小车．打开打点计时器电源释放小车获得一条带有点列的纸带． ③在获得的纸带上清晰的部分每5个间隔标注一个计数点ABC…测量相邻计数点的间距s1•s2•s3…．并将其记录在纸带上对应的位置处．已知实验装置中打点计时器的电源是频率为50Hz的低压交流电源图乙为用米尺测量所得纸带上的S1S2S3和S4的情况．由图可读出S1＝1.68cms₂＝2.42cmS3＝3.12cmS4＝cm．由此求得打下B点时小车速度大小vB＝m/s加速度的大小a＝m/s2计算结果取3位有效数字．
如图四边形ABCD是平行四边形平面AED⊥平面ABCDEF∥ABAB＝2BC＝EF＝1AE＝DE＝3∠BAD＝60°G为BC的中点． Ⅰ求证FG∥平面BED Ⅱ求证平面BED⊥平面AED Ⅲ求直线EF与平面BED所成角的正弦值．
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若电场强度加倍，小球运动的加速度大小为3 m/s2 若电场强度减半，小球运动到B.点时速度为初速度v0的一半 
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粒子穿过电场和磁场的时间之比
粒子穿过电场和磁场的时间之比
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