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如图所示，汽缸开口向上放在水平地面上，缸内用活塞封闭一段理想气体，活塞质量为m、截面积为S，活塞离缸底的距离为h，质量也为m的物块放在缸底，用细线与活塞相连，细线刚好伸直，活塞与汽缸内壁无摩擦且气密...
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高三下学期物理《》真题及答案
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如图所示绝热的汽缸与绝热的活塞
B.密封一定质量的空气后水平放置在光滑地面上，不计活塞与汽缸壁的摩擦，现用电热丝给汽缸内的气体加热，在加热过程中 （ ）A.汽缸向左移动
活塞A.B.均向左移动
密封气体的内能一定增加
汽缸中单位时间内作用在活塞A.和活塞B.的分子个数相同
导热良好的圆柱形汽缸置于水平地面上用质量为M.的光滑活塞密封一定质量的理想气体活塞横截面积为S.开始
一个木箱放在水平地面上小明通过一根跨过定滑轮的绳子用力竖直向上提木箱但木箱仍静止在水平地面上未动如
如图所示绝热汽缸固定在水平地面上汽缸内用绝热活塞封闭着一定质量的理想气体开始时活塞静止在图示位置现用
外界对汽缸内气体做正功
缸内气体的内能减小
缸内气体在单位时间内作用于活塞单位面积冲量增大
在单位时间内缸内气体分子与活塞碰撞的次数增加
【2017·开封市高三第一次模拟】如图所示一汽缸固定在水平地面上通过活塞封闭有一定质量的理想气体活塞
如图K54－3所示一个内壁光滑绝热的汽缸固定在地面上绝热的活塞下方封闭着空气若突然用竖直向上的力F.
每个分子对缸壁的冲力都会减小
单位时间内缸壁单位面积上受到的气体分子碰撞的次数减少
分子平均动能不变
若活塞重力不计，拉力F.对活塞做的功等于缸内气体内能的改变量
图K54－3
如图所示一长为L.内横截面积为S.的绝热气缸固定在水平地面上气缸内用一质量为m的绝热活塞封闭了一定质
如图所示水平地面上放置一个内壁光滑的绝热汽缸气缸开口朝上缸内通过轻质活塞封闭一部分气体．初态时气体
如图所示气缸放在地面上开口向上缸内质量为m的活塞与气缸内部无摩擦封闭一段理想气体绕过光滑定滑轮的轻
如图所示绝热气缸固定在水平地面上气缸内用绝热活塞封闭着一定质量的理想气体开始时活塞静止在图示位置现用
缸内气体对活塞做负功
缸内气体的内能减小
缸内气体在单位时间内作用于活塞单位面积的冲量增大
缸内气体分子在单位时间内与活塞碰撞的次数增加
一个内壁光滑绝热的气缸固定在地面上绝热的活塞下方封闭着空气若突然用竖直向上的力F.将活塞向上拉一些如
每个分子对缸壁的冲力都会减小
单位时间内缸壁单位面积上受到的气体分子碰撞的次数减少
分子平均动能不变
若活塞重力不计，拉力F.对活塞做的功等于缸内气体内能的改变量
如图所示一圆筒形汽缸静止于地面上汽缸的质量为M.容积为V.活塞连同手柄的质量不计汽缸内部的横截面积为
如图所示水平地面上放置一个内壁光滑的绝热汽缸气缸开口朝上缸内通过轻质活塞封闭一部分气体．初态时气体
有一传热良好的圆柱形气缸置于水平地面上并用一光滑的质量为M.活塞密封一定质量的的理想气体活塞面积为S
如图所示地面上有一质量M.=10kg的圆形汽缸缸内横截面积S.=0.01m2汽缸内有用一轻活塞封闭着
如图所示气缸竖直放在地面上气缸内用活塞封闭一定量的理想气体活塞的质量m=0.2kg活塞的面积S=1c
如图所示一长为L.内横截面积为S.的绝热气缸固定在水平地面上气缸内用一质量为m的绝热活塞封闭了一定质
如图1所示汽缸开口向右固定在水平桌面上气缺内用活塞横截面积为S封闭了一定质量的理想气体活塞与气缸壁之
如图所示一汽缸固定在水平地面上通过活塞封闭有一定质量的理想气体活塞与缸壁的摩擦可忽略不计活塞的截面积
―个质量为m的物体放在水平地面上物体上方安装一长度为L劲度系数为K的轻弹簧如图所示.现用手拉着弹簧上
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Whatcouldhomesofthefuturebelike?Nooneknowsexactly.Butpreparationsaremadefortheworld'sfirstfreeform3D﹣printedhouse. ExpertswillbuildahousecalledCurveAppealwhichwillbe3D﹣printedoff﹣sitebeforebeingputtogetheron﹣sitetocreatetwooutsidewallsaroofandaninsidepart.Thesefourmainpartswillthenbejoinedtogether. Although3D﹣printedbuildingshavebeenmadebeforethishome﹣﹣﹣tobebuiltinChattanoogaTennesseelaterthisyear﹣﹣﹣willbethefirstofitskindasitwillcontainnoregularshapesorangles.ThehouseisthecreationofthedesigncompanyWATGbasedinLondonandCalifornia.ThedesignforCurveAppealdrawsinspirationfromtheCaseStudyHouseprogram. Thearchitects建筑师leadingtheprogramwerefamousfortryingtocreateopen﹣planspacethataddsnaturallight.InawrittenstatementaspokesmanforWATGsaidUsingmanyofthesamemoderndesignprinciplesCurveAppealisthenextdevelopingstep.It'simportantthatthebuildingsandtheenvironmentworktogetherharmoniously.ThechosensiteforCurveAppealisstepsawayfromtheTennesseeRiverinabeautifulwoodedsunlitarea. WATGwasawardedthefirstprizeintheFreeformHouseDesignChallengein2016andgivenprizemoneyof﹩8000tomakeitsplansareality.Thecompetitionwasdesignedforarchitectsdesignersengineersandartists. Competitorswerechallengedtodesigna600to800﹣﹩qftsingle﹣familyhomethatrethinkstraditionalaesthetics美学constructionbuildingsystemsandstructure. OverthelastyearWATG'sChicagoofficehasbeendevelopingtheirdesignwithBranchTechnology.Thisprojectwillbecompletedlaterthisyear.OncecompletedtheCurveAppealhomewillhaveopenandlight﹣filledinsidelivingspace. 1WhatcanweknowaboutCurveAppealfromthepassage? A.Itwillbedifferentfromanordinaryhouse. B.Itisthefirst3D﹣printedbuilding. C.Ithasvisiblewallsbutnoroof. D.Itwaseverbuiltintheworld. 2Whereisthefreeform3D﹣printedhouselocatedaccordingtoParagraph4? A.FarawayfromtheTennesseeRiver. B.InthewoodsneartheTennesseeRiver. C.NearWATG'sChicagooffice. D.Nexttosomemodernbuildings. 3WhatdoestheFreeformHouseDesignChallengedo? A.Itinspirespeopletodesignwhattheylike. B.Itonlyacceptsdesignsintraditionalways. C.Itofferscompetitorsinspirationwhennecessary. D.Ithelpsputcreativeideasintopractice. 4What'sthepassagemainlyabout? A.Thedesignofhomesinfuture. B.TheFreeformHouseDesignChallenge. C.Theworld'sfirstfreeform3D﹣printedhouse. D.Thedevelopmentof3D'sprintinginarchitecture.
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Myfirstlessonwasatameeting.AswesettledaroundthetableIheardMegwhowas1arecentoperationtalkingtoJudiththemanagerofourprojectThankyousomuchfor2mydaughterstotheirdancelessonlastweek.Don'tmentionitJudithsaidItwasnothing. Knowinghow3JudithwaswithherworkkidsandagingparentsIfoundherdrivingMeg'schildrentodancelessonsunbelievably4. IwasabouttosaymoreaboutthiswhenDonnaanothercolleagueenteredtheroom5. Sheapologizedforbeinglatesayingshejusthadhostedalunchforherfriendswhowereoverseventy.ThatwassoniceofyouIsaid6howshedidn'tliketocookorclean.Ohshesaidwavingher7Itwasnothing.SomehowIcouldstilltellthe8inhervoice.Shegainedasenseofsatisfactionfromtheentertainment款待offeredtoherfriends. Seeingtheir9tohelpothersselflesslyIstartedthinkingabouttheconceptofnothingthispeacefulandgenerouswayofliving﹣﹣﹣wasitreallynothingorweretheysimplysayingthat?Isuddenly10thatonceIspentawholeafternoonafterworkhelpingafriend11aspeechshewasgoingtodeliver.I12hertorearrange重新安排theorderofthestoriesinthelecturetomakeitsoundmore13.Afterthefifthtryshefinally14it.Shehuggedmewith15sayingthankstome.Ismiledandsaiditwasnothing. SuddenlyIrealizedthathelpingsomeonewasreallysomethingtome.Ilearntthatgivingfromtheheartdoesn't16meanhardwork.The17isfindingsomethingwelovetodoandfindingsomeonewho18thatsomething.Ourgenerositycan19othersaswellasourselves.Onceyouhaveagood20ofitit'snothing.Andit'sreallysomething. 1A.recoveringfrom B.adaptingto C.goingthrough D.joiningin 2A.guiding B.fetching C.driving D.dragging 3A.common B.busy C.strange D.practical 4A.frightened B.sincere C.gifted D.generous 5A.hurriedly B.disappointedly C.angrily D.unexpectedly 6A.ignoring B.knowing C.forgetting D.predicting 7A.eyes B.feet C.leg D.hand 8A.pleasure B.sadness C.surprise D.regret 9A.progress B.adventure C.promise D.willingness 10A.referred B.refused C.remembered D.respected 11A.preparefor B.putup C.giveaway D.takeapart 12A.begged B.invited C.advised D.permitted 13A.unbelievable B.reasonable C.sensitive D.puzzling 14A.got B.meant C.caught D.made 15A.concern B.worry C.gratitude D.apology 16A.normally B.accidentally C.necessarily D.possibly 17A.treat B.trick C.belief D.plan 18A.needs B.admires C.loves D.defends 19A.defeat B.benefit C.win D.regard 20A.order B.balance C.impression D.command
杜氏肌营养不良症一般在3～5岁时开始发病20～30岁因呼吸衰竭而死亡受一对等位基因Dd控制．亨廷顿舞蹈症一般在中年发病受另一对等位基因Hh控制．如图是某家族两种遗传病系谱图其中Ⅰ3不携带致病基因．请回答 1利用DNA分子杂交技术鉴定Ⅰ3是否携带致病基因的原理是． 2该家族中杜氏肌营养不良症和亨廷顿舞蹈症的遗传方式分别是． 3Ⅰ4的基因型是．Ⅱ3产生同时含有两种致病基因卵细胞的概率是． 4Ⅲ3患杜氏肌营养不良症的概率是． 5若Ⅲ2与一正常男性婚配生一男孩该男孩正常的概率是．
利用科学记数法表示的数原来各是什么数-5.002×104＝
Fishingisapopularactivityandeveryfishermanknowstherule:Keepthebigonesthrowthesmalleronesback.Theideabehinditissimple﹣thelargerfishareprobablyolder.Ifyoukeepthesmalleronestheywon'tbeabletoreproduceandthefishpopulationwillbeindanger. Butfishingoutthelargestfishfromapopulationhasanunwantedeffect:Overtimefeweradultfishgetreallybig.Ifonlythesmallerfishreproducethenfuturegenerationswillbecomesmaller.Thisisanexampleofevolution进化inaction. OnescientistDr.DavidConoverhasspentthelastdecadestudyingtheeffectsofthekeepthebigonesruleandiftheycanbechanged. TosetuphisexperimentConoverandhisteamcaughthundredsofsilversidefishanddividedthemintosixgroups.FortwogroupsConoverfollowedtheukeepthelargeonesruleandtookoutthebiggestfish.Fortwoothergroupsheremovedonlythesmallfish.Forthelasttwogroupsheremovedfishatrandom随意的. Afterfiveyearshemeasuredthefishineachgroup.Inthetwogroupswherethelargestfishwereregularlyremovedtheaveragefishsizewassmallerthantheaveragesizeintheothergroups.Herewastheevolutioninaction:Ifonlysmallfishsurvivetoreproducethenfuturegenerationsoffishwillalsotendtobesmall. ForthesecondfiveyearsofhisexperimentConoverchangedtherulesandtookfishrandomlyfromeachgroup.Attheendoftheexperimenthefoundthatthefishthatwereinthekeepthelargeonesgroupforthefirstfiveyearshadstartedtogetlargeragainalthoughhecalculateditwouldtakeatleast12yearsforthefishinthatgrouptoreturntotheiroriginalsize. Inotherwordsittakeslesstimetoshrinkthanitdoestorecover. 1What'sthetraditionalruleinfishing? A.Keepbothbigandsmallones. B.Keepbigonesandfreesmallones. C.Keepsmallonesandthrowbigonesback. D.Keeptheonesthatcanreproduce. 2DavidConoverdidexperimentonfishinginorderto. A.findpracticalrulesinfishing B.provethetraditionalfishingrulewasreasonable C.seekforgoodfishestoreproduce D.findgoodmethodinraisingsilversidefish 3WhatdidDavidConoversexperimentprove? A.Fishermanshouldfishatcertaintime. B.Fishermanshouldkeepbigonesandfreesmallone. C.Fishermanshouldkeepsmallonesandthrowbigonesback. D.Fishermanshouldkeepfishatrandom. 4Whatdoestheunderlinedwordshrinkmeaninthelastparagraph? A.Becomesmaller. B.Becomeill. C.Becomeweaker. D.Becomeless.
下列关于人体内性激素的叙述正确的是
下列关于细胞生命历程的叙述正确的是
利用科学记数法表示的数原来各是什么数2×105=
如图是探究有关酶特性的实验装置将装置置于适宜温度下保温5min后向各试管中滴加斐林试剂并水浴加热2min观察试管中的颜色变化．相关叙述正确的是
科学家构建了含有大洋鳕鱼抗冻蛋白基因启动子和大鳞鲑鱼生长激素基因的表达载体并将其导入了大西洋鲑的细胞中获得了生长速度加快的转基因大西洋鲑．相关叙述正确的是
把下列数据用科学记数法表法出来地球上煤的储量估计为15万亿吨以上．
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