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如图所示的半圆形轨道，该轨道是用内壁光滑的薄壁细圆管弯成，放置在竖直平面内，圆半径比细管内径大得多，轨道底端与水平地面相切，轨道在水平方向不可移动．弹射装置将一个小球（可视为质点）从a点水平弹射向b...
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高三下学期物理《》真题及答案
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如图所示水平轨道AB与位于竖直平面内半径为R.的半圆形光滑轨道BCD相连半圆形轨道的BD连线与AB垂
如图所示ABDO是处于竖直平面内的固定光滑轨道AB是半径为R=15m的1/4圆周轨道半径OA处于水平
如图所示半径为R的竖直光滑半圆形轨道BC与光滑水平地面AB相切于B点弹簧左端固定在竖直墙壁上用一质量
如图所示质量为m的滑块在恒定的水平外力的作用下从水平轨道上的A.点由静止出发到B.点时撤去外力又沿竖
S.形玩具轨道如图所示固定在竖直平面内轨道的弯曲部分是用内壁光滑的薄壁细圆管弯成两个半径相等的半圆管
15分如图所示的S字形玩具轨道该轨道是用内壁光滑的薄壁细圆管弯成将轨道固定在竖直平面内轨道弯曲部分是
如图所示水平光滑轨道AB与竖直半圆形光滑轨道在B.点平滑连接AB段长x=10m半圆形轨道半径R.=2
14分如图所示水平轨道AB与位于竖直面内半径为R.=0.90m的半圆形光滑轨道BCD相连半圆形轨道的
如图所示ab是水平的光滑轨道bc是与ab相切的位于竖直平面内半径R.=0.4m的半圆形光滑轨道现在A
如图所示水平轨道AB与位于竖直面内半径为R.的半圆形光滑轨道BCD相连半圆形轨道的BD连线与AB垂直
如图9所示用内壁光滑的薄壁细圆管弯成的由半圆形APB圆半径比细管的内径大得多和直线BC组成的轨道固定
如图所示水平轨道AB与位于竖直面内半径为R.的半圆形光滑轨道BCD相连半圆形轨道的BD连线与AB垂直
如图所示质量为M.的小车静止在光滑的水平地面上车上装有半径为R.的半圆形光滑轨道现将质量为m的小球在
如图所示水平轨道AB与位于竖直面内半径为R.=0.90m的半圆形光滑轨道BCD相连半圆形轨道的BD连
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如图所示水平光滑轨道AB与竖直半圆形光滑轨道在B.点平滑连接AB段长x=2.5m半圆形轨道半径R.=
如图所示滑块在恒定外力F.＝2mg的作用下从水平轨道上的A.点由静止出发到B.点时撤去外力又沿竖直面
如图所示滑块在恒定的水平外力F.=2mg的作用下从水平轨道上的A.点由静止出发到B.点时撤去外力又沿
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8分Duringtherosyyearsofelementaryschool小学Ienjoyedsharingmydollsandjokeswhichallowedmetokeepmyhighsocialstatus.Iwasthequeenoftheplayground.Thencamemytweensandteensandmeangirlsandcoolkids.TheyroseintheranksnotbybeingfriendlybutbysmokingcigarettesbreakingrulesandplayingjokesonothersamongwhomIsoonfoundmyself. Popularityisawell﹣exploredsubjectinsocialpsychology.MitchPrinsteinaprofessorofclinicalpsychologysortsthepopularintotwocategoriesthelikableandthestatusseekers.Thelikables'plays﹣well﹣with﹣othersqualitiesstrengthenschoolyardfriendshipsjump﹣startinterpersonalskillsandwhentappedearlyareemployedeverafterinlifeandwork.Thenthere'sthekindofpopularitythatappearsinadolescencestatusbornofpowerandevendishonorablebehavior. EnviableasthecoolkidsmayhaveseemedDr.Prinstein'sstudiesshowunpleasantconsequences.Thosewhowerehighestinstatusinhighschoolaswellasthoseleastlikedinelementaryschoolaremostlikelytoengage从事indangerousandriskybehavior. InonestudyDr.Prinsteinexaminedthetwotypesofpopularityin235adolescentsscoringtheleastlikedthemostlikedandthehighestinstatusbasedonstudentsurveys调查研究.Wefoundthattheleastwell﹣likedteenshadbecomemoreaggressiveovertimetowardtheirclassmates.Butsohadthosewhowerehighinstatus.Itclearlyshowedthatwhilelikabilitycanleadtohealthyadjustmenthighstatushasjusttheoppositeeffectonus. Dr.Prinsteinhasalsofoundthatthequalitiesthatmadetheneighborswantyouonaplaydate﹣sharingkindnessopenness﹣carryovertolateryearsandmakeyoubetterabletorelateandconnectwithothers. InanalyzinghisandotherresearchDr.PrinsteincametoanotherconclusionNotonlyislikabilityrelatedtopositivelifeoutcomesbutitisalsoresponsibleforthoseoutcomestoo.Beinglikedcreatesopportunitiesforlearningandfornewkindsoflifeexperiencesthathelpsomebodygainanadvantagehesaid. 1Whatsortofgirlwastheauthorinherearlyyearsofelementaryschool? A.Unkind. B.Lonely. C.Generous. D.Cool. 2Whatisthesecondparagraphmainlyabout? A.Theclassificationofthepopular. B.Thecharacteristicsofadolescents. C.Theimportanceofinterpersonalskills. D.Thecausesofdishonorablebehavior. 3WhatdidDr.Prinstein'sstudyfindaboutthemostlikedkids? A.Theyappearedtobeaggressive. B.Theytendedtobemoreadaptable. C.Theyenjoyedthehigheststatus. D.Theyperformedwellacademically. 4Whatisthebesttitleforthetext? A.BeNice﹣YouWon'tFinishLast B.TheHighertheStatustheBetter C.BetheBest﹣YouCanMakeIt D.MoreSelf﹣ControlLessAggressiveness
如图ABC为固定在竖直平面内的轨道AB段为长0.75m的粗糙水平杆BC段为半径R＝2.5m圆心角θ＝10°的光滑圆弧AB相切于BC．穿在轨道上的小球在A处时速度水平向左大小为1.0m/s已知小球与AB之间的动摩擦因数μ＝0.05求g取10m/s2 1小球向左经过B点时的速度大小 2小球在圆弧上达到的最大高度 3小球从最大高度起需多长时间再次经过B点．
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30分Everyyearabout40000peopleattempttoclimbKilimanjarothehighestmountaininAfrica.They1withthemlotsofwaste.The2mightdamagethebeautyoftheplace.Theglaciers冰川aredisappearingchangingthe3ofKilimanjaro. HearingthesestoriesI'm4abouttheplace﹣otherdestinationsaredescribedaspurernaturalexperiences. HoweverIsoon5thatmuchhaschangedsincethedaysofdisturbingreportsof6amongtonsofrubbish.Ifinda7mountainwithtoiletsatcampsandalongthepaths.Theenvironmentalchallengesare8buttheeffortsmadebytheTanzaniaNationalParkAuthorityseemtobe9. ThebestofaKilimanjaro10inmyopinionisn'treachingthetop.Mountainsare11asspiritualplacesbymanycultures.This12isespeciallyevidentonKilimanjaroas13gothroughfiveecosystems生态系统inthespaceofafewkilometers.Atthebaseisarainforest.Itendsabruptlyat3000meters14landsoflowgrowingplants.Furtheruptheweather15﹣lowcloudsenvelopethemountainsideswhicharecoveredwiththickgrass.I16twelveshadesofgreenfromwhereIstand.Above4000metersisthehighland17gravel砾石stonesandrocks.18youclimbintoanarctic﹣likezonewith19snowandtheglaciersthatmaysoondisappear. DoesKilimanjaro20itsreputationasacrowdedmountainwithlinesoftouristsruiningtheatmosphereofpeace?Ifoundtheoppositetobetrue. 1A.keep B.mix C.connect D.bring 2A.stories B.buildings C.crowds D.reporters 3A.position B.age C.face D.name 4A.silent B.skeptical C.serious D.crazy 5A.discover B.argue C.decide D.advocate 6A.equipment B.grass C.camps D.stones 7A.remote B.quiet C.all D.clean 8A.new B.special C.significant D.necessary 9A.payingoff B.spreadingout C.blowingup D.fadingaway 10A.atmosphere B.experience C.experiment D.sight 11A.studied B.observed C.explored D.regarded 12A.view B.quality C.reason D.purpose 13A.scientists B.climbers C.locals D.officials 14A.holdingonto B.goingbackto C.livingupto D.givingwayto 15A.changes B.clears C.improves D.permits 16A.match B.imagine C.count D.add 17A.village B.desert C.road D.lake 18A.Obviously B.Easily C.Consequently D.Finally 19A.permanent B.little C.fresh D.artificial 20A.enjoy B.deserve C.save D.acquire
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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. Ibecameinterestinginplayingfootballthankstoasmallaccident.OneafternoonwhereIwasinprimaryschoolIwaswalkingbytheschoolplayground.Suddenlyfootballfelljustinfrontofmebutalmosthitme.Istoppedtheballandkickedithardlybacktotheplayground.Toeveryone′ssurprisingtheballwentintothenet.AllthefootballplayerontheplaygroundcheeredloudlysaythatIhadatalentforfootball.FromnowonIstartedtoplaymyfootballwithclassmatesafterschool.Iamagoodplayernow.
8分ForCanaanElementary'ssecondgradeinPatchogueN.Y.todayisspeechdayandrightnowit'sChrisPalaez'sturn.The8﹣year﹣oldisthejokeroftheclass.Withshiningdarkeyesheseemslikethekindofkidwhowouldenjoypublicspeaking. Buthe'snervous.I'mheretotellyoutodaywhyyoushould…should…Christripsonthe﹣ldapronunciationdifficultyformanynon﹣nativeEnglishspeakers.HisteacherThomasWhaleyisnexttohimwhisperingsupport.…Votefor…me…ExceptforsomestumblesChrisisdoingamazinglywell.WhenhebringshisspeechtoaniceconclusionWhaleyinvitestherestoftheclasstopraisehim. AsonofimmigrantsChrisstartedlearningEnglishalittleoverthreeyearsago.Whaleyrecalls回想起howatthebeginningoftheyearwhencalledupontoreadChriswouldexcusehimselftogotothebathroom. LearningEnglishasasecondlanguagecanbeapainfulexperience.Whatyouneedisagreatteacherwholetsyoumakemistakes.IttakesalotforanystudentWhaleyexplainsespeciallyforastudentwhoislearningEnglishastheirnewlanguagetofeelconfidentenoughtosay‘Idon'tknowbutIwanttoknow.' Whaleygottheideaofthissecond﹣gradepresidentialcampaignprojectwhenheaskedthechildrenonedaytoraisetheirhandsiftheythoughttheycouldneverbeapresident.Theanswerbrokehisheart.Whaleysaystheprojectisaboutmorethanjustlearningtoreadandspeakinpublic.Hewantsthesekidstolearntoboast夸耀aboutthemselves. BoastingaboutyourselfandyourbestqualitiesWhaleysaysisverydifficultforachildwhocameintotheclassroomnotfeelingconfident. 1WhatmadeChrisnervous? A.Tellingastory. B.Makingaspeech. C.Takingatest. D.Answeringaquestion. 2Whatdoestheunderlinedwordstumblesinparagraph2referto? A.Improperpauses. B.Badmanners. C.Spellingmistakes. D.Sillyjokes. 3WecaninferthatthepurposeofWhaley'sprojectisto. A.helpstudentsseetheirownstrengths B.assessstudents'publicspeakingskills C.preparestudentsfortheirfuturejobs D.inspirestudents'loveforpolitics 4WhichofthefollowingbestdescribesWhaleyasateacher? A.Humorous. B.Ambitious. C.Caring. D.Demanding.
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25分假定你是李华美国朋友David来信说他对中国的丝绸文化以及一带一路倡议很感兴趣请给他回信要点如下 1丝绸始于新石器时代 2原料为蚕茧兼具高雅与环保 3古丝绸之路对世界文化交流的作用 4一带一路倡议将产生的深远影响. 注意1.词数100左右 2.可适当增加细节以使行文连贯. 参考词汇一带一路倡议theBeltandRoadInitiative 新石器时代NeolithicAge蚕茧cocoon
10分Ifyou'regoingabroadforcollegeyoumightbethinkingabouthowtogetyourselfasafeandcozyhomefortheyearsahead.Ofcoursedormitoriesarealwaysagoodplacetostart.butsomelargestatecollegesrequirejuniorstoliveoffcampusduetothelimitednumberofdormrooms.1. Howtofindahouse2.Ifyouarejustafreshmanordon'tknowmanypeopledon'thesitatetoapproachsomeupperclassmeninyourclassesorclubs.Moreoftenthannotupperclassmenhavemoreexperiencewithrentingandaremorefamiliarwiththeareayourschoolisin. Anothergoodideaistotalktoseniorswhoarecurrentlylivingoff﹣campus.Theseseniors'landlordswillmostlikelybelookingfornewtenants房客aftergraduation. Alsoregisteredrealtors房地产经纪人mightbeabletofindyouaplaceforafee.InadditionFacebookgroupscanalsoprovidesomeusefulinformation.3. Roommates Havingroommatescannotonlysaveussomemoneybutalsogiveusvaluablecom﹣panionship.Howeverrememberthatfindingtherightroommatesforyouisthemostimportantthingotherthansafetyconcerns.4definitelydonotlieaboutyourpreferencesscheduleorhabitseveniftalkingaboutthemcouldmakeyouuncomfortable.Ontheothersidealsoremembertoaskyourpotentialroommatestotellyouaboutthemselvesindetail. 5pleasedoeverybodyafavorbybeingupfrontaboutit.Constantlyrunninginto conflictswithyourquietroommateisdefinitelythelastthingyouwant. A.Ifyouareapartyanimal B.Whilelookingforroommates C.Getalongwellwithyourroommates D.Whenhavingachatwithyourroommate E.Firstyoucanaskyourfriendswhoarealreadylivingoffcampus F.Howeverbereallycarefulifyougetintouchwithstrangersthroughtheinternet G.Nonethelessrentinganapartmentcangiveyousomehands﹣onexperiencewithliving
VisitorsstillstopattheoldhouseinScituateMassachusetts.Butthehouseisnotwhatbringsthemthere.Whattheywanttoseeistheoldstonewellbesideit﹣andtheiron﹣boundwaterbucketthat'sputonitsedge. TwohundredyearsagothisfarmhousewasthehomeofSamuelWoodworth.DuringthelongsummersofhischildhoodyoungSamuelwouldoftenpauseatthewell.Itwasawelcomebreakespeciallyonahotafternoon.Onsuchadayhewouldeagerlydrawabucketfulofcoldwaterandsatisfyhisthirstwitharefreshingdrink. WhenhewasfourteenWoodworthleftScituateforNewYorkCitywherehestartedhisownnewspaper.Laterheworkedasaneditoratothernewspapersandmagazineswhilewritingnovelsplaysandpoetryinhissparetime.Hislifewasbusyandherarelyhadtimetovisitthefamilyfarm. ButWoodworthneverstoppedthinkingofhisScituatehome.AfterworkoneeveningWoodworthpouredhimselfaglassofcitywater.AfterthatheremarkedtohiswifeLydiahowwonderfulitwouldbetohavealongcooldrinkfromtheoakenbucketathisfather'swell.LydiahadasuggestionWhynotputittopoetry? ItwasasuggestionWoodworthcouldnotresist.ThatnighthewroteTheBucket.Inithecapturedtheworldofhischildhoodonahotsummerdayandthesimplejoyofstoppingforadrinkathisfather'swell. Hispoemwasaninstantsuccess.Itseemedtotoucheveryonewhohadeverbeenhomesick.AttheheightofitspopularityTheOldOakenBucketasitcametobecalledwastranslatedintofourlanguagesandthewordsweresettoapopulartuneofthetime.OvertheyearscountlesspeoplehavereadorsungWoodworth'sodetohisboyhood.TodayitistheofficialsongofScituateMassachusetts. 1Whydoestheauthoruseflashback倒叙inParagraph2? A.Tohelpreadersappreciatethewellwater. B.Tohelpreadersenjoycitylife. C.TohelpreadersunderstandhowhardWoodworthwas. D.TohelpreaderslearnaboutWoodworth'schildhoodlife. 2WhatwasWoodworth'spurposeforwritingthepoem? A.Tosharehisopinion. B.Tointroducehishometown. C.Toexpresshisemotion. D.Tomakesomecomplaints. 3Whatcanweinferfromthetext? A.Thewaterinthewelltastedbetterthanthatinthecity. B.ThewellandthewaterhadadeepimpressiononSamuel'smind. C.Woodworth'swiferemindedhimofthewellandsuggestedputtingittopoetry. D.Notmanypeoplepaidmuchattentiontothepoematfirst. 4Whichofthefollowingcanbethebesttitleforthetext? A.TheOldOakenBucket B.LivinginNewYork C.GrowingupontheFarm D.GoodSuggestionsfromWife
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8分ExpertssaythatiffoodwereacountryitwouldranksecondbehindtheUSasoneofthebiggestgreenhousegaspolluters.Thereasonistherisingdemandformeat.Animalfarmingisresponsiblefor14.5percentofglobalgreenhousegasmethane甲烷emissions排放.Whilecowsaretheworsecontributorspigssheepdonkeysandotheranimalsplayapartaswell. Animalagriculturealsocauseslandtobecomedamagedwatertobepollutedandforeststogetdestroyed.Withtheworldpopulationforecasttoriseto9.8billionby2050thingsareonlylookingworseforouralreadydecreasingnaturalresourcesWhilegoingvegetarian素食的wouldhelpmeatconsumptiontoodeep﹣rootedinmostwesterndietstoallowforsuchasharppermanentchange.Thatiswhyexpertsareadvocatingsubstitutingsomeofthebeefchickenorporkwithordinaryinsects! Insectswhichgrowintoadultswithinamatterofmonthsifnotweeksarereadyforconsumptionmuchfasterthandomestic驯养的animals.TheyalsorequiremuchlessroomuselesswaterandfoodandproducefarlessgreenhousegasthananimalsOftheI.Imillioninsectspeciesworldwidescientistshaveidentified1.700aseatable.Amongthemareantsgrasshoppersgrubsandearthworms.Justlikeanimalseachinsecthasadifferenttaste.TreewormstastejustlikeporkandgrubsaresimilartosmokedmeatWhileeatinginsectsmightbeanewconceptforWesternpeopleover2billionpeopleworldwideconsumeinsectsasaregularpartoftheirdiet.Besidesbeingdeliciousinsectsarehighinproteinhaveveryfewcaloriesandarefreeofthesaturated饱和atfoundinanimalmeatInsectscanbepreparedinmanyways.Creativecookscanusetemtocookprotein﹣richsoupmakebakedtreatsandevenfryafewwithvegetables.Soeatinsects﹣bothyourbodyandMotherEarthwillthankyouforit! 1Whichofthefollowinganimalsareresponsibleforthemostglobalmethaneemissions? A.Cows B.Pigs C.Sheep D.Donkeys 2Howisthethirdparagraphmainlydeveloped? A.Byaskingquestions B.Byprovidingexamples. C.Bylistingthenumbers D.Bymakingcomparisons. 3Whatdotreewormstastelike? A.Pigmeat B.Tomatosoup C.Freshvegetables. D.Friedchicken. 4Whatcanbeinferredfromthelastparagraph? A.Fewpeopleeatinsectsregularly. B.Ordinaryinsectsarehighinfat. C.Saturatedfatisharmfultohealth. D.Insectscontainvariousvitamins
原子核是由质子和中子组成的它们统称为．核电站是利用选填“重核裂变”“轻核聚变”或“化学反应”获得核能并将其转为电能．
宇航员的航天服内充有气体若出舱前航天服内气体压强为p体积为V到达太空后气体体积变为2V温度不变此时航天服内的气体压强为．1965年3月18日苏联航天员列昂诺夫在返回飞船时遇到了意想不到的困难他的航天服有些向外膨胀很难从密封舱的接口处钻回舱内他启动了应急装置减小航天服的体积安全地回到密封舱内．你认为该应急装置可以如何减小航天服体积．
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甲乙两个弹簧振子它们的振动图象如图所示则可知两弹簧振子
Whyshouldmankindexplorespace?Whyshouldmoneytimeandeffortbespentexploringandresearchingsomethingwithsofewapparentbenefits?WhyshouldresourcesbespentonspaceratherthanonconditionsandpeopleonEarth?Thesearequestionsthatunderstandablyareveryoftenasked. Perhapsthebestanswerliesinourgeneticmakeupashumanbeings.Whatdroveourancestorstomovefromthetreesintotheplainsandonintoallpossibleareasandenvironments?Thewiderthespreadofaspeciesthebetteritschanceofsurvival.Perhapsthebestreasonforexploringspaceisthisgenetictendencytoexpandwhereverpossible. Nearlyeverysuccessfulcivilizationhasexploredbecausebydoingsoanydangersinsurroundingareascanbeidentifiedandpreparedfor.Withoutknowledgewemaybecompletelydestroyedbythedanger.Withknowledgewecanlessenitseffects. Explorationalsoallowsmineralsandotherpotentialresourcestobefound.Evenifwehavenoimmediateneedofthemtheywillperhapsbeusefullater.Resourcesmaybemorethanphysicalpossessions.Knowledgeortechniqueshavebeenacquiredthroughexploration.Thetechniquesmayhavemedicalapplicationswhichcanimprovethelengthorqualityofourlives.Wehavealreadybenefitedfromotherspin﹣offsincludingimprovementsinearthquakepredictioninsatellitesforweatherforecastingandincommunicationssystems.Evennon﹣stickpansandmirroredsunglassesareby﹣productsoftechnologicaldevelopmentsinthespaceindustry! Whilemanyresourcesarespentonwhatseemsasmallreturntheexplorationofspaceallowscreativebraveandintelligentmembersofourspeciestofocusonwhatmayservetosaveus.Whilespacemayholdmanywondersandexplanationsofhowtheuniversewasformedorhowitworksitalsoholdsdangers.Thedangerexistsbutknowledgecanhelphumanbeingstosurvive.Withouttheabilitytoreachoutacrossspacethechancetosaveourselvesmightnotexist. WhileEarthistheonlyplanetknowntosupportlifesurelytheadaptiveabilityofhumanswouldallowustoliveonotherplanets.Itistruethatthelifestylewouldbedifferentbuthumanlifeandcultureshaveadaptedinthepastandsurelycouldinthefuture. 1Whydoestheauthormentionthequestions? A.Toexpresshisdoubts. B.Tocomparedifferentideas. C.Tointroducepointsfordiscussion. D.TodescribetheconditionsonEarth. 2Whatisthereasonforexploringspacebasedon? A.Humansarenatureborntodoso. B.Humanshavethetendencytofight. C.Humansmayfindnewsourcesoffood. D.Humansdon'tliketostayinthesameplace. 3Theunderlinedwordspin﹣offsinParagraph4probablyrefersto. A.survivalchances B.unexpectedbenefits C.potentialresources D.physicalpossessions 4Whichofthestatementscanbestsumupthepassage? A.Spaceexplorationhascreatedmanywonders. B.Spaceexplorationprovidesthebestvalueformoney. C.Spaceexplorationcanbenefitscienceandtechnology. D.SpaceexplorationmayhelpusavoidpotentialproblemsonEarth.
JoiningUsasaGamesVolunteer! Thesuccessofthe2020TokyoOlympicGamesdependsonyourcontribution!JoinusasaGamesVolunteer! GamesvolunteerswillbedirectlyinvolvedinassistingGamesoperationsbefore.duringandaftertheTokyo2020GamesGamesvolunteerswillguideathletesaroundwelcomeimportantpeopleandhelplostvisitors NumberofVolunteeringDaysandDailyHours ※TheTokyoOlympicGameswillbeheldfromFriday24JulytoSunday9August2020.InprincipleGamesvolunteerswillberequiredtoworkforatleastafortnightbeforeduringandaftertheOlympicGames. ※Gamesvolunteerswillworkapproximatelyeighthoursperdayincludingrestbreaks.Actualshiftlengthsdependoneventschedulesactivitiesactivitysitesetc. AgeandResidentialRequirements Applicantsmustfulfillthefollowingtworequirements ※BornonorbeforeApril12002 ※JapanesenationalorpersonwithvalidvisapermittingresidenceinJapanduringthevolunteerperiodtemporaryvisitorsincluded.NativespeakersofEnglishwillbepreferred. NumberofGamesVolunteerOpportunities 80000 MethodandApplicantCategories ※Applicationswillbesubmittedonline ※Individualsonly OffersandConfirmation Thoseapplicantswhoattendthetrainingsessions会议andareassignedavolunteerrolewillbeofferedtobecomeaTokyo2020Gamesvolunteer. Pleasenotethattheaboveofferwillbecancelledintheeventofanyofthefollowing ※IfthevolunteerengagesinanyactivitythatdamagestheimageoftheTokyo2020Games ※Ifthevolunteerengagesinanyactivitythatseverelydamagesteamwork ※Ifanyinformationcontainedintheoriginalapplicationformisclearlyfoundtobefalse ItemsandWelfaresProvidedtoVolunteers VolunteerswillbeprovidedwithasetoffreeOlympicGamesvolunteeruniformsandmealsduringtheworkday. 1AGamesvolunteerwillberequiredtoworkforatleast. A.oneweek B.twoweeks C.threeweeks D.fourweeks 2WhowillbemorelikelytobeacceptedasaGamesvolunteer? A.AChinese B.ARussian C.AnAustralian D.AGerman 3WhatwillGamesvolunteersbeprovidedwithforfree? A.Accommodation. B.Clothing. C.Transportation. D.Amusements
15分LastyearmybrotherandIwenttoMiamiforavacation.Someofmyfriendswhohadbeentherebeforesaiditwas1wonderfulholidaydestination.Beforewewentwehadplannedformonths.Whenthedaycamewewereready. Sinceitwasthefirsttimewe2betherewewereprettyexcited.Afterourplanelandedwewenttothehotel.Wehadmade3wereservationsixmonths4earlybutthemanatthefrontdesksaidtherehadbeenamistake.We5tellthatourroomshadn'tbeenreservedforthatweek6fortheweekafter.Ididn'tunderstandwhythiswouldhappenandmycreditcardhadalreadybeenchargedforthereservation.What'sworsethehotelhadbeenfullybooked.Whenwe7wonderwhattodothemanagercameout.Shewas8surprisehelpful.SheapologizedforthemistakeandgaveusaspareVIProomonthetopfloor.Wehadneverstayedinsuchanamazingroomandweweren'tchargedextra. ThenextdaymybrotherandIwenttothebeach9somepeoplewereplayingvolleyball.Wegotalittle10sunburnbutthedayhadbeensorelaxingthatwedidn'tmind.
磁体的磁感线是
电场强度定义式为E＝也可用类似的方法来描述地球产生的引力场中某点的场的强弱．已知地球质量为M半径为R地表处重力加速度为g引力常量为G一质量为m的物体位于距地心2R处的某点则该点处引力场强度为
太阳是一颗自己能发光发热的气体星球它的能量来自于反应．行星在太阳的引力作用下几乎在同一平面内绕太阳公转距离太阳越近的行星公转周期大小越．
图甲是沙摆装置细沙均匀漏出同时匀速拉动纸板．图乙是细沙在纸板上形成的曲线其粗细不均匀主要是因为沙漏从最高点摆动到最低点的过程中
在一只锥形瓶中放入一个气球把气球的开口翻在锥形瓶的瓶颈上如图所示然后向气球吹气将会发生的现象是已知在封闭瓶口时瓶内被封闭的气体体积V压强p0．若忽略气球薄膜产生的弹力认为气球内外压强相等同时忽略吹气时温度变化．在人吹出的气体压强达到1.1p0时气球的体积增加量为V．
如图所示一足够长的固定斜面的倾角为θ＝37°质量m＝1kg的物体受到平行于斜面的力F作用由静止开始运动．力F随时间t变化规律如右图所示以平行于斜面向上为正方向g＝10m/s2sin37°＝0.6cos37°＝0.8物体与斜面间的滑动摩擦因数为0.25求 1第1s内物体运动的加速度大小a1 2第2s内物体运动的加速度大小a2 3第1s末物体的动能的大小EK1 4请描述物体在第4s内的受力情况或画出受力分析图并说明理由．
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