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交通信号灯有红、黄、绿三种颜色，关于这三种信号灯发出的单色光，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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遇到交通信号灯和交通警察指挥不一致时要按照交通信号灯通行
交通信号灯由哪几种颜色构成分别表达何种意义
在路口遇有交通信号灯和现场交通警察指挥不一致时按照交通信号灯通行
交通信号灯由红绿蓝灯组成
普通交通信号灯按自上而下或自左向右排列
红、黄、绿
黄、红、绿
绿、黄、红
红、绿、黄
交通信号灯包括
交通信号灯、交通标志、交通标线
绿灯、红灯和黄灯信号
直行信号、左转弯信号、停止信号
在路口遇有交通信号灯和交通警察指挥不一致时按照交通信号灯通行
下列关于交通信号灯正确的说法是.
交通信号灯共有三种颜色的灯组成
红灯表示禁止通行
黄等表示警示
以上都是
风险信号灯是以三种颜色来进行识别现场的危险
红；
蓝；
黄；
绿；
道路交通信号灯是指用灯光颜色向交通参与者发出特定的指示禁止警示等信号的专用灯具
交通信号包括和交通警察的指挥
交通信号灯
交通标志
交通信号灯、交通标志、交通标线
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DT WhenBarbraStreisanddiscoveredin2003thataphotographofherCaliforniabeachhousewasamong12000photosontheInternetaspartofacollectionbyphotographerKennethAdelmanshedidwhatanyfamouspersonwoulddohithimwitha﹩50millionlawsuit.Butintryingtoholdbacktheimagesshecausedadifferentoutcome.Herlegalactionsledtoalmosthalfamillionpeoplevisitingthewebsiteviewingandcopyingthephotoswithinamonth. EversincethentheeffectoflettingpublicknowsomethingyouaretryingtokeepsecrethasbeencalledtheStreisandeffect.TheproblemforanyonetryingtosuppressinformationisthattheInternetistheworld'sbiggestandmostefficientcopyingmachine.Putadocumentontoaconnectedmachineanditwillspread.Sowhenyouwanttobefamousyoucan'tbutifyoufindyourselfinthespotlightandwanttoeraseyourselfyoucannot. ThereisnoshortageofexamplesoftheStreisandeffect.Nine﹣year﹣oldMarthaPaynecreatedasimpleblogpostingthemealsherschoolserved.Shetookaphotoofwhatwasbarelyafillingmealbyanyone'sstandards.WiththephotoshefilledacommentNowDadunderstandswhyIamhungrywhenIgethome.ThethingdidnotgotoofaruntilthelocalauthoritybannedlittleMarthafromdoingthatagain.MarthapostedasupposedlyfinalpostcalledGoodbyeexplainingeverything.Oncethemediafoundthisoutthingswentfrombadtoworsefortheauthority.Nowthebloghasmorethan9.5millionpageviews.MarthahasevenexpandedherblogbyincludingpicturesofschoolmealstakenbyotherkidsfromallovertheworldlikeGermanyandJapan. Wecanfindsimilarexamplesthroughouthistorytobefrank.ManhasexperiencedtheStreisandeffecteversincethebirthofmasscommunication.Whydoesitexist?Everytimeyouaretoldnottoseewhat'sinthesecretshinyboxwrappedingiftpaperyou'regoingtodoeverythinginyourpowertodoexactlythat!Justrealizingthatknowingsomethingaboutsomeoneisharmfultotheirstatuswewillwanttoknowthatpieceofinformation.Thisisexactlythehumannature.Thisiswhatlawyersandauthoritiesshouldbefamiliarwith.Unfortunatelyafewofthemfailtograspit. 1.TheunderlinedwordsuppressinParagraph2probablymeans. A.giveaway B.lookinto C.coverup D.searchfor 2.WhatspeededupthespreadofMartha'sstory? A.Parents'complaints. B.Theauthority'sorder. C.Thephotosofotherkids. D.Supportingfromtheschool. 3.Whatisthelastparagraphmainlyabout? A.TherootofStreisandeffect. B.TheinfluenceofStreisandeffect. C.People'sreactiontoStreisandeffect. D.HistoricalexamplesofStreisandeffect.
Morestudentsthaneverbeforearetakingagap﹣year间隔年beforegoingtouniversity.Itusedtobecalledtheyearoffbetweenschoolanduniversity.Thegap﹣yearphenomenonoriginated起源withthemonthsleftovertoOxbridgeapplicantsbetweenentranceexamsinNovemberandthestartofthenextacademicyear. Thisyear25310studentswhohaveacceptedplacesinhighereducationinstitutionshaveputofftheirentryuntilnextyearaccordingtostatisticsonuniversityentranceprovidedbyUniversityandCollegeAdmissionsSerbiceUCAS. Thatisarecord14.7%increaseinthenumberofstudentstakingagapyear.TonyHigginsfromUCASsaidthatthestatisticsaregoodnewsforeveryoneinhighereducation.Studentswhotakeawell﹣plannedyearoutaremorelikelytobesatisfiedwithandcompletetheirchosencourse.Studentswhotakeagapyearareoftenmorematureandresponsiblehesaid. Butnoteveryoneishappy.OwainJamesthepresidentoftheNationalUnionofStudentsNUSarguedthattheincreaseisevidenceofstudenthadship﹣youngpeoplearebeingforcedintoearningmoneybeforefinishingtheireducation.Newstudentsarenowawarethattheyarelikelytoleaveuniversityupto￡15000indebt.Itisnotsurprisingthatmoreandmorestudentsaretakingagapyeartoearnmoneytosupporttheirstudyforthedegree.NUSstatisticsshowthatover40%ofstudentsareforcedtoworkduringtermtimeandthefigureincreasesto90%duringvacationperiodshesaid. 29.Whatdowelearnaboutthegapyearfromthetext? A.Itisflexibleinlength. B.Itisatimeforrelaxation. C.Itisincreasinglypopular. D.Itisrequiredbyuniversities. 30.AccordingtoTonyHigginsstudentstakingagapyear. A.arcbetterpreparedforcollegestudies B.knowalotmoreabouttheirfuturejobs C.aremorelikelytoleaveuniversityindebt D.haveabetterchancetoentertopuniversities 31.HowdoesOwainJamesfeelaboutthegap﹣yearphenomenon? A.He'spuzzled. B.He'sworried. C.He'ssurprised. D.He'sannoyed. 32.WhatwouldmoststudentsdoontheirvacationaccordingtoNUSstatistics? A.Attendadditionalcourses. B.Makeplansforthenewterm. C.Earnmoneyfortheireducation. D.Preparefortheirgraduatestudies.
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Theadobedwellings土坯房61buildbythePuebloIndiansoftheAmericanSouthwestareadmiredbyeven62mostmodernofarchitectsandengineers.Inadditiontotheirsimplebeautywhatmakestheadobedwellingsadmirableistheir63abletoairconditionahousewithout64useelectricequipment.Wallsmadeofadobetakeintheheatfromthesunonhotdaysandgiveoutthatheat65slowduringcoolnightsthuswarningthehouse.Whenanewdaybreaksthewallshavegivenuptheirheatandarenowcoldenough66coolthehouseduringthehotday67thesametimetheywarmupagainforthenightThiscycle68godayafterdayThewallswarmupduringthedayandcooloffduringthenightandthusalwaysatimelyoffset抵消fortheoutsidetemperatures.As69naturearchitectsthePuebloIndiansfiguredoutexactly70thicktheadobewallsneededtobetomakethecycleworkonmostdays. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.
Yourhousemayhaveaneffectonyourfigure.Expertssaythewayyoudesignyourhomecouldplayaroleinwhetheryoupackonthepoundsorkeepthemoff.Youcanmakeyourenvironmentworkforyouinsteadofagainstyou.Herearesomewaystoturnyourhomeintopartofdietplan. Openthecurtainsandturnupthelights.Darkenvironmentsaremorelikelytoencourageovereatingforpeopleareoftenlessself﹣consciouswhenthey'reinpoorlylitplaces﹣andsomorelikelytoeatlotsoffood.Ifyourhomedoesn'thaveenoughwindowlightgetmorelampsandfloodtheplacewithbrightness. Mindthecolors.Researchsuggestswarmcolorsfuelourappetites胃口.Inonestudypeoplewhoatemealsinablueroomconsumed消耗33percentlessthanthoseinayelloworredroom.Warmcolorslikeyellowmakefoodappearmoreappetizingwhilecoldcolorsmakeusfeellesshungry.Sowhenit'stimetorepaintgoblue. Don'tforgettheclock﹣﹣﹣ortheradio.Peoplewhoeatslowlytendtoconsumeabout70fewercalories卡路里permealthanthosewhorushthroughtheirmeals.Beginkeepingtrackofthetimeandtrytomakedinnerlastatleast30minutes.Andwhileyou'reatitactuallysitdowntoeat.Ifyouneedsomehelpslowingdownturnonrelaxingmusic.Itmakesyoulesslikelytorushthroughameal. Downsizethedishes.Bigservingbowlsandplatescaneasilymakeusfat.Weeatabout22percentmorewhenusinga12﹣inchplateinsteadofa10﹣inchplate.Whenwechoosealargespoonoverasmalleronetotalintake摄入jumpsby14percent.Andwe'llpourabout30percentmoreliquidintoashortwideglassthanatallskinnyglass. 1.Thetextisespeciallyhelpfulforthosewhocareabout. A.theirhomecomforts B.theirbodyshape C.housebuying D.healthydiets 2.Ahomeenvironmentinbluecanhelppeople. A.digestfoodbetter B.regaintheirappetites C.burnmorecalories D.reducefoodintake 3.Whatarepeopleadvisedtodoatmealtimes? A.Fatquickly. B.Playfastmusic. C.Usesmallerspoons. D.Turndownthelights. 4.Whatcanbeasuitabletitleforthetest? A.IsYourHouseMakingYouFat? B.WaysofServingDinner C.EffectsofSelf﹣Consciousness D.IsYourHomeEnvironmentRelaxing?
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如图所示用半径相同的AB两球的碰撞可以验证“动量守恒定律”．实验时先让质量为m1的A球从斜槽轨道上某一固定位置S由静止开始滚下从轨道末端抛出落到位于水平地面的复写纸上在下面的白纸上留下痕迹．重复上述操作10次得到10个落点痕迹．再把质量为m2的B球放在斜槽轨道末端让A球仍从位置S由静止滚下与B球碰撞后分别在白纸上留下各自的落点痕迹重复操作10次．MPN为三个落点的平均位置． ①实验中直接测定小球碰撞前后的速度是不容易的．但是可以通过测量间接地解决这个问题． A．小球开始释放高度hB．小球抛出点距地面的高度HC．小球做平抛运动的射程 ②以下提供的测量工具中本实验必须使用的是多选． A．刻度尺B．天平C．游标卡尺D．秒表 ③关于本实验下列说法正确的是． A．斜槽轨道必须光滑B．斜槽轨道末端必须水平C．实验过程中复写纸和白纸都可以移动 ④在实验误差允许范围内若满足关系式则可以认为两球碰撞前后总动量守恒． A．m1．OP＝m1．OM+m2•ONB．mc．OP＝m1．ON+m2．OM C．m1．OM＝m1．OP+m2．OND．m1．ON＝ml．OP+m2．OM ⑤在实验中为了让A球碰后沿原方向运动应满足A球的质量m1大于B球的质量m2请推理说明．
如图所示一理想变压器的原线圈接正弦交流电源副线圈接有电阻R和小灯泡．电流表和电压表均可视为理想电表．闭合开关S下列说法正确的是
光子除了有能量还有动量．若光子能量为E动量为J则光子动量p＝式中c为真空中的光速．当光照射到物体表面上时不论光被物体吸收还是被物体表面反射光子的动量都会发生改变因而对物体表面产生一种压力． 如图是1901年俄同物理学家列别捷夫测量光压的实验装置．T型架通过悬丝竖直悬挂横臂水平悬丝一端同定在横臂中点．在横臂的两侧有圆片P和Q两圆片与T型架在同一竖直平面内．圆片P是涂黑的当光线照射到P上时可以认为光子全部被吸收圆片Q是光亮的当光线照射到Q上时可以认为光子全部被反射．分别将光线照射在P或Q上都可以引起悬丝的旋转．在悬丝上固定一__面M用一细光束照射时就可以获知悬丝扭转的角度．已知光速为c两个圆片PQ的半径都为r．悬丝转过的角度与光对网片的压力成正比． a．用光强单位时间内通过与传播方向垂直的单位面积的光能为I0的激光束垂直照射整个圆片P求激光束对圆片P的压力F2的大小 b．实验中第一次用光强厶为的激光束单独照射整个圆片P平衡时光束与圆片垂直且悬丝有一扭转角第二次仍用该光束单独照射整个圆片Q平衡时光束与圆片不垂直悬丝的扭转角与第一次相同．求激光束与圆片Q所在平面的夹角φ．
Mycolortelevisionhasgivenmenothingbutaheadache.IwasabletobuyitalittleoverayearagobecauseIhadmyrelativesgivememoneyformybirthdayinsteadofalotofclothesthatwouldn'tfit.IletasalesclerkfoolmeintobuyingadiscontinuedmodelIrealizedthisadaylatewhenIsawnewspaperadvertisementsforthesetatseventy﹣fivedollarslessthanIhadpaidThesetworkedsobeautifullywhenIfirstgotithomethatIwouldkeepitonuntilstationssignedoffforthenightFortunatelyIdidn'tgotanychannelsshowingall﹣nightmoviesorIwouldneverhavegottentobed. ThenIstarteddevelopingaproblemwiththesetthatinvolvedstatic静电noise.Forsomereasonwhencertainshowsswitchedintoacommercialaloudnoisewouldsoundforafewseconds.GraduallythisnoisebegantoappearduringashowandtogetridofitIhadtochangetoanotherchannelandthenchangeitback.SometimesthistechniquewouldnotworkandIhadtopickupthesetandshakeittoremovethesound.Iactuallybegantobuildupmyarmmuscles肌肉shakingmyset. WhenneitherofthesemethodsremovedthestaticnoiseIwouldsithelplesslyandwaitforthenoisetogoaway.AtlastIendeduphittingthesetwithmyfistanditstoppedworkingaltogether.Mytriptotherepairshopcostme$62andthesetisworkingwellnowbutIkeepexpectingmoretrouble. 21.WhydidtheauthorsayhewasfooledintobuyingtheTVset? A.Hegotanoldermodelthanhehadexpected. B.Hecouldn'treturnitwhenitwasbroken. C.Hecouldhaveboughtitatalowerprice. D.Hefailedtofindanymovieshowsonit. 22.WhichofthefollowingcanbestreplacethephrasesignedoffinParagraph1? A.endedalltheirprograms B.providedfewerchannels C.changedtocommercials D.showedall﹣nightmovies 23.HowdidtheauthorfinallygethisTVsetworkingagain? A.Byshakingandhittingit. B.Byturningitonandoff. C.Byswitchingchannels. D.Byhavingitrepaired. 24.Howdoestheauthorsoundwhentellingthestory? A.Curious B.Anxious C.Cautious D.Humorous.
直流电动机的基本结构由永磁铁和矩形线圈构成如图1所示．现将标有“3V3W”的直流电动机串联一个滑动变阻器接在电动势为E＝4.0V内阻为r＝0.40Ω的电源的两端如图2所示．已知电动机线圈的电阻R0＝0.10Ω不计其它电阻． 1若滑动变阻器接入电路的阻值R1＝3.5Ω且电动机卡住不转求此时电路中的电流I1． 2调节滑动变阻器接入电路的阻值或电动机工作时的负载发生变化回路中的电流I及电源的输出功率P随之改变． a．请从理论上推导P与I的关系式并在图3中定性画出P﹣I图象 b．求该电源对外电路能够输出的最大功率Pm． 3调节滑动变阻器接入电路的阻值使电动机正常工作．现保持滑动变阻器接入电路的阻值不变增加电动机的负载电动机将通过转速调节达到新的稳定状态．请分析说明在这个过程中电路中的电流如何变化．
物质W是一种含氮有机物会污染土壤．W在培养基中达到一定量时培养基表现为不透明．某研究小组欲从土壤中筛选出能降解W的细菌目标菌．回答下列问题． 1要从土壤中分离目标菌所用选择培养基中的氮源应该是． 2在从土壤中分离目标菌的过程中发现培养基上甲乙两种细菌都能生长并形成菌落如图所示．如果要得到目标菌应该选择菌落进一步纯化．选择的依据是． 3土壤中的某些微生物可以利用空气中的氮气作为氮源若要设计实验进一步确定甲乙菌能否利用空气中的氮气作为氮源请简要写出实验思路预期结果和结论即． 4该小组将人工合成的一段DNA转入大肠杆菌使大肠杆菌产生能降解W的酶酶E．为了比较酶E与天然酶降解W能力的差异该小组拟进行如下实验请完善相关内容． ①在含有一定浓度W的固体培养基上A处滴加含有酶E的缓冲液B处滴加含有相同浓度天然酶的缓冲液C处滴加三处滴加量相同． ②一段时间后测量透明圈的直径．若C处没有出现透明圈说明若AB处形成的透明圈直径大小相近说明．
Theadobedwellings土坯房61buildbythePuebloIndiansoftheAmericanSouthwestareadmiredbyeven62mostmodernofarchitectsandengineers.Inadditiontotheirsimplebeautywhatmakestheadobedwellingsadmirableistheir63abletoairconditionahousewithout64useelectricequipment.Wallsmadeofadobetakeintheheatfromthesunonhotdaysandgiveoutthatheat65slowduringcoolnightsthuswarningthehouse.Whenanewdaybreaksthewallshavegivenuptheirheatandarenowcoldenough66coolthehouseduringthehotday67thesametimetheywarmupagainforthenightThiscycle68godayafterdayThewallswarmupduringthedayandcooloffduringthenightandthusalwaysatimelyoffset抵消fortheoutsidetemperatures.As69naturearchitectsthePuebloIndiansfiguredoutexactly70thicktheadobewallsneededtobetomakethecycleworkonmostdays. 61. 62. 63. 64. 65. 66. 67. 68. 69. 70.
某课题组就固氮菌和纤维素分解菌混合培养对纤维素降解的效果进行研究实验步骤大致如下取250mL三角瓶装入50mL基础培养基接种不同比例的混合菌种放入滤纸条150r/min摇床振荡培养．根据滤纸条的分解情况测定纤维素酶的活性实验结果如表． 1上述实验中培养基中填需要”或“不需要”加入琼脂滤纸条的作用是． 2完成上述实验时还必须进行． 3由上表可得出如下实验结论． 4有同学推测混合培养也能促进固氮菌的生长理由是．若想比较IIIIIIV组的固氮菌数目实验思路如下最后统计各组固氮菌的菌落数．
Trainingforamarathonrequirescarefulpreparationandsteadygradualincreasesinthelengthoftheruns.36buythebest﹣fittingbest﹣builtrunningshoesyoucanfind.Noonecansaywhichbrandwillworkbestforyouorfeelbestonyourfeetsoyouhavetorelyonyourexperienceandonthefeelofeachpairasyoushop.Whenyouhavefoundshoesthatseemrightwalkinthemforafewdaystodouble﹣checkthefit.37.Asalwaysyoushouldstretch伸展atleasttenminutesbeforeeachruntopreventinjuries. Duringthefirstweekdonotthinkaboutdistancebutrunfiveminuteslongereachday.38itiswisetotakeadayofftorest.Butduringthenextweeksetagoalofatleastamileandahalfperrun.39.Aftertwoweeksstarttimingyourself.40.Dependingonthekindofraceyouplantoenteryoucansetupatimetablefortheremainingweeksbeforetherace. A.Aftersixdays B.Foragoodmarathonrunner C.Beforeyoubeginyourtraining D.Witheachdayincreasethedistancebyahalfmile E.Iftheystillfeelgoodyoucanbeginrunninginthem F.Timespentforpreparationraisesthequalityoftraining G.Nowyouarereadytofigureoutagoalofimprovingdistanceandtime. 36. 37. 38. 39. 40.
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