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在如图甲所示的电路中，理想变压器原、副线圈匝数比为2：1．a，b两端电压与时间的关系如图乙所示，二极管可视为理想二极管，电表均为理想电表，电阻R＝10Ω，则下列说法正确的是（ ）
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高三下学期物理《》真题及答案
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一理想变压器原副线圈的匝数比为101原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为50Hz
副线圈输出电压的有效值为31V
P.向右移动时，原、副线圈的电流比减小
P.向右移动时，变压器的输出功率增加
理想变压器原副线圈的匝数比为10:1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为100 Hz
理想交流电压表的示数为31.1V.
P.向下移动时，变压器原、副线圈中电流都变大
P.向上移动时，变压器的输出功率增大
有一理想变压器的原副线圈的匝数比为10:1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示
副线圈输出电压的有效值为3V
副线圈输出电压的频率为50Hz
P.向右移动时，原、副线圈的电流比变小
P.向右移动时，灯泡L.变亮
理想变压器原副线圈的匝数比为101.原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为100Hz
副线圈输出电压的有效值为31V
P向下移动时，原、副线圈的电流都减小
P向下移动时，变压器的输出功率增加
一台理想变压器原副线圈匝数之比是5∶1则原副线圈两端电压之比为_______这台变压器工作时原副线圈
一理想变压器原副线圈的匝数比为10∶1原线圈输入电压的变化规律如下图甲所示副线圈所接电路如图乙所示P
副线圈输出电压的频率为50Hz
副线圈输出电压的有效值为31V
P.向右移动时，原、副线圈的电流比减小
P.向右移动时，变压器的输出功率减小
理想变压器原副线圈的匝数比为10:1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为100Hz
副线圈输出电压的有效值为31V
P.向下移动时，原、副线圈的电流都减小
P.向下移动时，变压器的输出功率增加
一台理想变压器原副线圈匝数之比是5∶1则原副线圈两端电压之比为________这台变压器工作时原副线
一理想变压器原副线圈的匝数比为10:1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.
副线圈输出电压的频率为50Hz
副线圈输出电压的有效值为31V
P向右移动时，原、副线圈的电流比减小
P向右移动时，变压器的输出功率增加
一理想变压器原副线圈的匝数比为10∶1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.
副线圈输出电压的频率为50 Hz
副线圈输出电压的有效值为31V.
P.向右移动时，原、副线圈的电流比减小
P.向右移动时，变压器的输出功率增加
一台理想变压器的原副线圈的匝数比等于101这台变压器工作时原线圈上的交流频率与副线圈的交流频率之比为
理想变压器原副线圈的匝数比为10:1原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为100 Hz
理想交流电压表的示数为31.1V.
P.向下移动时，变压器原、副线圈中电流都变大
P.向上移动时，变压器的输出功率增大
如图3所示理想变压器原副线圈接有相同的灯泡A.B原副线圈的匝数之比为n1∶n2=2∶1交变电源电压为
一理想变压器原副线圈的匝数比为101原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为
副线圈输出电压的频率为50Hz
副线圈输出电压的有效值为31V
P.向右移动时，原、副线圈的电流比减小
P.向右移动时，变压器的输出功率增加
一理想变压器原副线圈的匝数比为4∶1.原线圈接在一个交流电源上交流电的变化规律如图所示.副线圈所接的
副线圈输出交流电的周期为0.02s
副线圈输出电压为55V
流过副线圈的电流是5A
变压器输入、输出功率之比为4∶1
理想变压器原副线圈的匝数比为10:1.原线圈输入电压的变化规律如图5甲所示副线圈所接电路如图5乙所示
副线圈输出电压的频率为100Hz
理想交流电压表的示数为31V
P.向下移动时，变压器原副线圈中电流都变大
P.向下移动时，变压器的输出功率增大
如图所示理想变压器原副线圈匝数之比为31电流电压为u两灯完全相同则副线圈的输出电压是多少
理想变压器原副线圈的匝数比为101原线圈输入电压的变化规律如图甲所示副线圈所接电路如图乙所示P.为滑
副线圈输出电压的频率为50Hz
副线圈输出电压的有效值为3lV
P.向右移动时，原、副线圈的电流比减小
P.向右移动时，变压器的输出功率减小
如图所示原副线圈匝数比为2∶1的理想变压器正常工作时以下说法不正确的是
原、副线圈磁通量之比为2∶1
原、副线圈电流之比为1∶2
输入功率和输出功率之比为1∶1
原、副线圈磁通量变化率之比为1∶1
如图所示变压器可视为理想变压器在原副线圈的回路中分别接有阻值相同的电阻原线圈一侧接有一正弦交流电源若
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下列说法正确的是
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﹣Mr.Huhaveyoufinishedcorrectingthepapers? ﹣Notyetthepapers_______.You_______gettheresultsfrommebytomorrow. A.arecorrectedwill B.arebeingcorrectingshould C.arebeingcorrectedshall D.arebeingcorrectedwould
Ifyoufeelstressedbyresponsibilitiesatworkyoushouldtakeastepbackandidentify识别thoseof61greatandlessimportance.Thenhandlethemostimportanttasksfirstsoyou'llfeelarealsenseof62achieve.Leavingthelessimportantthingsuntiltomorrow63beoftenacceptable.Mostofusaremorefocused64ourtasksinthemorningthanwearelaterintheday.Sogetanearlystartandtrytobeasproductive65possiblebeforelunch.Thiswillgiveyoutheconfidenceyouneedtogetyouthroughtheafternoonandgohomefeelingaccomplished.Recent66studyshowthatwearefarmoreproductiveatworkifwetakeshortbreaks67regular.Giveyourbodyandbrainarestbysteppingoutsidefor68whileexercisingordoingsomethingyouenjoy.Ifyoufindsomethingyoulovedoingoutsideoftheofficeyou'llbelesslikely69bringyourworkhome.Itcouldbeanything﹣gardeningcookingmusicsports﹣butwhateveritis70makesureit'sarelieffromdailystressratherthananotherthingtoworryabout.
10分Therelationshipbetweenexerciseandcancerhaslongbothintriguedandpuzzledoncologistsandexercisephysiologists.Exerciseisstronglyassociatedwithloweredrisksformanytypesofcancer.Atthesametimeexerciseinvolvesbiologicalstresswhichtypicallyleadstoashort﹣termincreaseininflammation发炎whichcancontributetohigherrisksformanycancers.Nowanewstudyinmicemayoffersomecluesintotheexercise﹣cancerparadox.Itsuggeststhatexercisemaychangehowtheimmunesystemdealswithcancerbyboostingadrenaline肾上腺素certainimmunecellsandotherchemicalsthattogethercanreducetheseverityofcancerorfightitoffaltogether.TotrytobetterunderstandhowexercisecanbothelevateinflammationandsimultaneouslyprotectthebodyagainstcancerscientistsattheUniversityofCopenhageninDenmarkandotherinstitutionsdecidedtocloselyexaminewhathappensinsidemiceathighriskforthedisease.Soforthenewstudytheybeganbygatheringagroupofadultlabmice.Theseanimalsgenerallyliketorun.Thescientiststhenimplantedmelanoma黑素瘤skincancercellsintothemicebeforeprovidinghalfofthemwithrunningwheelsintheircageswhiletheotheranimalsremainedsedentary.Afterfourweeksfarfeweroftherunnershaddevelopedfull﹣blownmelanomathanthesedentarymiceandthosethathadbeendiagnosedwiththediseaseshowedfewerandsmallerlesions.Theydrewbloodfromboththeexercisingandsedentaryanimalsandcellsfromanytumorsinbothgroups.Asexpectedtheyfoundmuchhigherlevelsofthehormoneadrenalineinthebloodoftheexercisinganimalsespeciallyrightaftertheyhadbeenworkingoutonthewheelsbutalsoatothertimesoftheday.Thebodyreleasesadrenalineinresponsetoalmostanytypeofstressfulexperienceincludingexercise.Theyalsofoundhigherlevelsofinterleukin﹣6inthebloodoftherunners.Thisisasubstancethatisreleasedbyworkingmusclesandisbelievedtobothincreaseanddecreaseinflammationinthebodydependingonwhereandhowitgoestowork.Perhapsmostimportanttheyfoundmuchhighernumbersinthebloodstreamsofrunnersthaninthesedentarymiceofatypeofimmunecellnamednaturalkillercellsthatareknowntobestrongcancerfighters.Sothescientistsrepeatedtheiroriginalexperimentmultipletimesinducingcancerwhileallowingsomemicetorunandotherstosit.Insomeofthesefollow﹣upexperimentsthescientistsinjectedtherunnerswithasubstancethatblockedtheproductionofadrenalineandgavesedentaryanimalslargedosesofaddedadrenaline.Whattheynowfoundwasthatwhenrunningmicecouldnotproduceadrenalinetheydevelopedcanceratthesamerateasthesedentaryanimalswhilethesedentaryanimalsthathadbeeninjectedwithextraadrenalinefoughtofftheirtumorsbetterthanothersittingmice.Moreremarkablythescientistsdeterminedthatadrenalineseemedtobesendingbiochemicalsignalstosomeoftheanimals'IL﹣6cellsmakingthemphysiologicallymorealertsothatwhenatumorbegantodevelopintheaffectedanimalthoseIL﹣6cellsinturnactivatedthenaturalkillercellsinthebloodstreamandactuallydirectedthemtothetumorslikeminuteguidefish.Withtheseresults'weshowthatvoluntarywheelrunninginmicecanreducethegrowthoftumorsandwehaveidentifiedanexercise﹣dependentmobilizationofnaturalkillercellsastheunderlyingcauseofthisprotection'saidPernilleHojmanaresearcherattheUniversityofCopenhagenwhooversawthenewstudy.Itperhapsprovidesonemoreincentiveforustogetupandmove.1TherelationshipbetweenexerciseandcancerhaslongpuzzledoncologistsandexercisephysiologistsbecauseA.exerciseisstronglyassociatedwithloweredrisksformanytypesofcancer.B.exercisecanbothelevateinflammationwhichcancontributetohigherrisksformanycancersandmeanwhileprotectthebodyagainstcancer.C.exercisemaychangecanreducetheseverityofcancerorfightitoffaltogether.D.exercisecanleadtoashort﹣termincreaseininflammationwhichcancontributetoelevatedrisksformanycancers.2Inthefirstexperimentwhichoneisthemostimportantresultthescientistsfound?A.naturalkillercellsaremuchmoreinthebloodstreamsofrunnersthaninthesedentarymice.B.levelsofinterleukin﹣6arehigherinthebloodoftherunnersthaninthesedentarymice.C.exercisesuchasrunningseemedtohelpthemicefightagainstthecancer.D.adrenalinecanreducetheseverityofcancerorfightitoff.3Whatdoestheunderlinedword'sedentary'mean?A.runB.moveC.sitD.sleep4Inthefollow﹣upexperimentsthescientistsfound?A.thehormoneadrenalinehasmuchhigherlevelsinthebloodoftheexercisinganimals.B.howtheseelementsintherunners﹣theirincreasedadrenalineIL﹣6andnaturalkillerimmunecellsfightagainsttumor.C.interleukin﹣6canbothincreaseanddecreaseinflammationinthebodydependingonwhereandhowitgoestowork.D.whathappensinsidemiceathighriskforthedisease.5Accordingtothestudywecaninferthefundamentalsubstancetofightthecanceroffis.A.adrenalineB.interleukin﹣6C.naturalkillercellsD.genes
设集合A＝{124}B＝{x|x2﹣4x+m＝0}．若A∩B＝{1}则B＝
设ω＞0函数y＝sinωx++2的图象向右平移个单位后与原图象重合则ω的最小值是
某化学小组为了研究外界条件对化学反应速率的影响进行了如下实验 【实验原理】2KMnO4+5H2C2O4+3H2SO4═K2SO4+2MnSO4+10CO2↑+8H2O 【实验内容及记录】 请回答 1根据表中的实验数据可以得到的结论是． 2利用实验1中的数据计算用KMnO4表示的化学反应速率为． 3该小组同学根据经验绘制了nMn2+随时间变化的趋势如图1所示但有同学查阅已有的实验资料发现该实验过程中nMn2+随时间变化的实际趋势如图2所示． 该小组同学根据图2所示信息提出了新的假设并继续进行实验探究． ①该小组同学提出的假设是． ②请你帮助该小组同学完成实验方案并填写表中空白 ③若该小组同学提出的假设成立应观察到现象．
Focusingontheunfairnessofcircumstanceskeepsyoucomparingyourselveswithothers_____appreciatingyourownspecialuniqueness. A.ratherthan B.morethan C.betterthan D.otherthan
已知△ABC的面积是AB＝1则AC＝
AnewcollectionofphotosbringsanunsuccessfulAntarcticvoyagebacktolife.FrankHurley'spictureswouldbeoutstanding﹣﹣﹣﹣undoubtedlyfirst﹣ratephoto﹣journalism﹣﹣﹣iftheyhadbeenmadelastweek.Infacttheywereshotfrom1914through1916mostofthemafteradisastrousshipwreck海难byacameramanwhohadnoreasonableexpectationofsurvival.Manyoftheimageswerestoredinanicechestunderfreezingwaterinthedamagedwoodenship.TheshipwastheEnduranceasmalltightNorwegian﹣builtthree﹣masterthatwasintendedtotakeSirErnestShackletonandasmallcrewofseamenandscientists27meninalltothesouthernmostshoreofAntarctica'sWeddellSea.FromthatpointShackletonwantedtoforceapassagebydogsled雪橇acrossthecontinent.ThejourneywasintendedtoachievemorethanwhatCaptainRobertFalconScotthaddone.CaptainScotthadreachedtheSouthPoleearlyin1912buthaddiedwithhisfourcompanionsonthemarchback.AswriterCarolineAlexandermakesclearinherforcefulandwell﹣researchedstoryTheEnduranceadventuringwaseventhenathoroughlycommercialeffort.Scott'slastjourneycompletedasbelayinatentdyingofcoldandhungercaughttheworld'simaginationandafilmmadeinhishonordrewcrowds.ShackletonaonetimeBritishmerchant﹣navyofficerwhohadgottowithin100milesoftheSouthPolein1908startedabusinessbeforehis1914voyagetomakemoneyfrommovieandstillphotography.FrankHurleyaconfidentandgiftedAustralianphotographerwhoknewtheAntarcticwashiredtomaketheimagesmostofwhichhaveneverbeforebeenpublished.33.WhatdoweknowaboutthephotostakenbyHurley?A.TheyweremadelastweekB.TheyshowedunderseasceneriesC.TheywerefoundbyacameramanD.Theyrecordedadisastrousadventure34.WhoreachedtheSouthPolefirstaccordingtothetext?A.FrankHurleyB.ErnestShackletonC.RobertFalconScottD.CarolineAlexander35.WhatdoesAlexanderthinkwasthepurposeofthe1914voyage?A.ArtisticcreationB.ScientificresearchC.MoneymakingD.Treasurehunting.
Mostofemployersareplanningtocutdownonwagesinsteadoflayingoffemployees______theeconomicdepression. A.indefenseof B.withregardto C.onbehalfof D.inresponseto
如图所示装置工作时均与H2有关． ①图1所示装置中阳极的电极反应式为． ②图2所示装置中通入H2一极的电极反应式为． ③某同学按图3所示装置进行实验实验结束后将玻璃管内固体物质冷却后溶于稀硫酸充分反应后滴加KSCN溶液溶液不变红再滴入新制氯水溶液变为红色．该同学据此得出结论铁与水蒸气反应生成FeO和H2．该结论填“严密”或“不严密”你的理由是用离子方程式表示．
现有强酸甲溶液的pH＝1强酸乙溶液的pH＝2则酸甲与酸乙的物质的量浓度之比不可能的是
﹣﹣﹣CanIreallygetanapple6plusasarewardifIwinthecompetition? ﹣﹣﹣Absolutely!________. A.Sowillyou B.Italldepends C.Imeanit D.That'sallright
为了探究AgNO3的氧化性和热稳定性某化学兴趣小组设计了如下实验． Ⅰ．AgNO3的氧化性 将光亮的铁丝伸入AgNO3溶液中一段时间后将铁丝取出．为检验溶液中Fe的氧化产物将溶液中的Ag+除尽后进行了如下实验．可选用试剂①KSCN溶液②NaOH溶液③酸性KMnO4溶液④K3[FeCN6]溶液． 1请完成下表 【实验结论】Fe的氧化产物为Fe2+和Fe3+ Ⅱ．AgNO3的热稳定性 用如图所示的实验装置A加热固体产生红棕色气体在装置D中收集到无色气体．当反应结束以后试管中残留固体为黑色． 2装置B的作用是． 3经小组讨论并验证该无色气体为O2其操作方法是． 4[查阅资料】①Ag2O和粉末的Ag均为黑色②Ag2O可溶于氨水． 【提出假设】试管中残留的黑色固体可能是①Ag②Ag2O③Ag和Ag2O． 【实验验证】该小组为验证上述设想分别取少量黑色固体进行了如下实验 【实验评价】根据上述实验不能确定固体产物成分的实验是填实验编号． 【实验结论】根据上述实验结果得出AgNO3固体受热分解的化学方程式为． 【实验拓展】另取2.0gAgNO3样品充分受热分解共收集到标准状况下气体的体积为336mL则样品中AgNO3的百分含量为．
8分2015WasaWarmWildYear.What'sNext?2015sawthingsheatupandgetoutofhandandnotjustinpolitics.ArecordwarmDecemberraisedaveragetemperaturesenoughtomake2015thesecondhottestyearonrecordinthecontiguousUnitedStatesaccordingtotheNationalOceanicandAtmosphericAdministration'sNationalClimateMonitoringAnnualReportwhichwasreleasedThursday.TheUnitedNationshadpreviouslyreportedthat2015wasshapinguptobethewarmestyearonrecordforthewholeplanet.LastyearwasalsothethirdwettestonrecordintheU.S.andsawtenweather﹣orclimate﹣relateddisastersthateachcausedatleast﹩1billionindamageintheU.S.andkilledatotalof155people.Theseincludeadroughttwofloodsfiveseverestormsawildfireandawinterstorm.TheaverageU.S.temperaturewas54.4°F2.4°Fabovethe20thcenturyaverageandsecondonlyto2012'srecordwarmth.Thiswasalsothe19thconsecutiveyearwithaveragetemperaturesabovetheaverageforthecentury.Everystatereportedabove﹣averageannualtemperatures.ThewarmingwasparticularlypronouncedacrossmostoftheeasternhalfofthecountryinDecemberwhenmanyplacessawtemperatures30degreesabovenormalandmanyrecordswereset.ThismirroredchangesseenintheArcticthatmonthwhentemperaturesspikedto50degreesabovenormal.PartofthiswarmingwasdrivenbyastrongElNiñoorperiodicwarminginthePacificOceanbutsomeofitcanalsobeattributedtoglobalwarmingsaysmeteorologistEricHolthauswhowasnotinvolvedwiththefederalreport.TheanalysiscomeslessthanamonthaftertheU.S.and194othercountriessignedanagreementinParistomoreaggressivelycountertheeffectsofclimatechange.'EvenifalltheinitialtargetsinParisaremetwe'llonlybepartofthewaytherewhenitcomestoreducingcarbonfromtheatmosphere'saidPresidentBarackObamaatthetime.Stilltheagreementrepresented'aturningpoint'bysettingup'thearchitecture'fordoingsohesaid.NOAA'sclimatemonitoringcenterdoesn'tissuepredictionsforfutureweatherbuttheagency'sClimatePredictionCenterdoes.Thatteam'sforecastforthenextthreemonthscallsforwarmer﹣than﹣averagetemperaturesinmuchofthecountryalthoughpartsofTexasandtheSoutheastmaybealittlecoolerthanusual.AsLancasterUniversityProfessorGailWhitemantoldtheWeatherChannel'climatechangemeansextremeweatheristhenewnormal.'1AccordingtothepassagethewarmestyearintheU.S.isA.2014B.2015C.notmentionedD.20122Accordingtothepassagewhichstatementisright?A.2015wasthethirdwettestyearonrecordinthewholeplanet.B.Tenweather﹣orclimate﹣relateddisastersintheU.S.includeadroughttwofloodsfourseverestormstwowildfiresandawinterstorm.C.The20thcenturyaveragetemperatureintheU.S.was52°F.D.ThewarmingwaspronouncedacrossmostofthewesternhalfofthecountryinDecember.3TheagreementtheUS.and194countriessignedaimedtoA.reducecarbonfromtheatmosphereB.countereffectsofclimatechange.C.setupthearchitectureD.findartificialwaystocooldowntheextremeweather4WhatdoesProfessorGailWhitemanmeaninthefuture?A.Extremeweatherwillbecommoninthefuture.B.Climatechangewillbenormal.C.Extremeweatherwillbenormalifwedon'ttakemeasures.D.Climatechangeleadtoextremeweather.
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