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数学课本的封面是一个长方形． （判断对错）
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一张长方形纸片剪下一个正方形剩下一个长方形称为第一次操作在剩下的长方形纸片中再剪下一个正方形剩下一个
一个正方形和一个长方形周长相等那么正方形的面积等于长方形的面积．．判断对错
一个长方形的长和宽同时扩大到原来的10倍这个长方形的面积就扩大到原来的10倍．．判断对错
用两个相同的正方形拼成一个长方形这个长方形的周长是两个正方形周长的和．．判断对错
一个长方形的长增加50%宽减少50%长方形的面积不变．．判断对错
用一些长12厘米宽8厘米的小长方形来拼一个正方形至少需要24个这样的长方形．．判断对错
两个边长是1厘米的正方形拼成一个长方形这个长方形的周长是6厘米．．判断对错
长方体的6个面一定都是长方形的正方体的6个面一定都是正方形的． 判断对错
两个边长2厘米的正方形拼成一个长方形则长方形的周长等于两个正方形的周长之和．．判断对错
把一个长方形按41的比放大放大后的长方形的面积比原来的扩大4倍．．判断对错
将一个长方形的铁丝框架拉成一个平行四边形它的面积和原来的长方形面积相等．．判断对错
小学数学课本的形状是
长方形
正方形
长方体
正方体
在一个长方形里画一个最大的三角形这个三角形的面积等于长方形面积的一半．．判断对错
用同样长的绳子围成一个长方形和一个正方形长方形的面积较小．判断对错
把一个圆平均分成若干等分拼成一个近似的长方形拼成的长方形和圆周长和面积都相等．．判断对错
把一个长方形按14缩小缩小后长方形与原来长方形的面积比是14．．判断对错
用两个大小相同的正方形拼成一个长方形长方形的面积与两个正方形的面积之和相等．．判断对错
一个长方形的周长是32厘米把它剪成两个完全相同的长方形每个长方形的周长都是16厘米．判断对错
把一个圆等分成若干份拼成一个近似的长方形这个长方形的面积与原来的圆形相同周长也与原来的圆形相同．．判
把两个长方形拼成一个大长方形面积不变判断对错
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在2016年2月举行的跳水世界杯比赛中我国运动员取得了很好的成就．在跳板比赛中若某运动员可看作质点其速度与时间关系图象如图所示t＝0是其向上起跳瞬间则下列说法正确的是
如图所示一列简谐横波沿x轴正方向传播在x轴上有PMQ三点从波传到x＝5m的点时开始计时已知t1＝0.5s时x＝7m的M点第一次出现波峰．求 ①这列波传播的速度 ②从t＝0时刻起到t2＝0.85s止质点Qx＝9m通过的路程保留至小数点后一位
质量为19Kg速度为3m的冰壶甲与静止的相同冰壶乙发生对心正碰碰后甲以1m/s的速度继续向前滑行．求 ①碰后瞬间冰壶乙的速度大小 ②若碰撞时间为0.1s则乙对甲的作用力大小．
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为了更方便监控高温锅炉外壁的温度变化在锅炉的外壁上镶嵌一个导热性能良好的汽缸汽缸内气体温度可视为与锅炉外壁温度相等．汽缸开口向上用质量为m＝1kg的活塞封闭一定质量的理想气体活塞横截面积为S＝1cm2．当汽缸内温度为300K时活塞与汽缸底间距为L活塞上部距活塞L处有一用轻质绳悬挂的重物M．当绳上拉力为零时警报器报警．已知室外空气压强p0＝1.0×105Pa活塞与器壁之间摩擦可忽略．求 ⅰ当活塞刚刚碰到重物时锅炉外壁温度为多少 ⅱ若锅炉外壁的安全温度为900K那么重物的质量应是多少
如图所示三个质量相同的均匀带电绝缘球ABC用三根轻质细线连接小球所在空间存在水平方向的匀强电场三根细线与竖直方向的夹角分别为30°45°60°不考虑小球之间的相互作用则下列说法中正确的是
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如图一定质量的理想气体由状态a沿abc变化到状态c吸收了340J的热量并对外做功120J．若该气体由状态a沿adc变化到状态c时对外做功40J则这一过程中气体填“吸收”或“放出”J热量．
Iwasdrowningindepression.SeveralmonthsagoI'd41allmysavingsandincomefrommyjob.SoImovedtoafarminthemountainshopingtoforgetmy42.HereIthoughteverythingwasgreyandIcouldn'tseeanyother43. Thenonedaythephoneranganditwasaladyontheotherend44purchasinghensanddirections.Igaveherthe45andsetupan46thefollowingmorning.AndthenshetoldmeaboutJackherlittleboywithautism自闭症.Shewantedto47himandIsaidyes. Thenat11a.m.thenextmorningacar48.IheadedforourgateandbeforeIcouldreachitalittleboywasrunningtowardsme49callingoutJanet﹣I'mJack.I50himcarryingadinosaurbook.Wewerecarriedoffintothefarmwithdinosaur51. Wereachedthehenarea.Jackchosethreebabyhensandhetoldthemthey'd52withhimforever.AsJackwaslettingthebabiesknowhowwellhe'd53themmyfancyblackroostercameuptous.IaskedJackifheeverheldaroosterand54Jackwassittingonapieceofwoodwiththeroosteronhislap55ofthemcooing咕咕叫ateachother. We56thehenswithJack'sparentsbehindus.JackandIweredeepin57aboutanimalsuntilwegottotheircar.FinallyIsaid58toJackandweallwaved. Thelightdrovedownmydriveway59somethingpleasantwasleftbehind.AndIheldontoJack'slightuntilIstarteda60lifeformeandmyanimals. 41.A.reduced B.spent C.preserved D.lost 42.A.memories B.worries C.fears D.challenges 43.A.sign B.shadow C.color D.design 44.A.askingabout B.decidingon C.insistingon D.puttingforwards 45.A.instruction B.opinion C.price D.information 46.A.schedule B.appointment C.business D.record 47.A.join B.comfort C.bring D.treat 48.A.stopped B.crashed C.brokedown D.droveoff 49.A.nervously B.shyly C.unwillingly D.excitedly 50.A.imagine B.remember C.recommend D.watch 51.A.statements B.origins C.stories D.reports 52.A.live B.play C.study D.wander 53.A.dealwith B.worryabout C.makeuseof D.takecareof 54.A.suddenly B.immediately C.slowly D.carefully 55.A.all B.none C.both D.neither 56.A.kept B.approached C.caught D.left 57.A.thought B.conversasion C.love D.life 58.A.sorry B.thanks C.goodbye D.hello 59.A.but B.as C.since D.for 60.A.successful B.healthy C.balanced D.new
如图所示电源电动势为E内阻为r电路中的R2R3分别为总阻值一定的滑动变阻器R0为定值电阻R1为光敏电阻其电阻随光照强度增大而减小当开关S闭合电容器中一带电微粒恰好处于静止状态下列说法中正确的是
请修改下面的短文.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. InDecember9anEnglishspeechcontestisheldinourcity.36studentsfrom15 schoolstookpart.ThecontestmadeupofthreeroundsanEnglishspeechanswering thequestionsandatalentshow.EverystudentmadeaexcellentspeechinEnglish whichthemewasaboutTheBeautyofOurCity.Whentheyansweredthequestions theyfeltconfidentlyofsucceeding.Inthetalentshowcolorfulperformancesgivenbyher weremorethanattractive.There'snodoubtaboutthatthiscontestwasahugesuccess. Throughtheactivitythestudentshavelearntalot.Theyhavenotonlyimprovedtheir speakingEnglishandalsoenjoyedasenseofachievement.
“用DIS研究加速度与力的关系”的实验装置如图a所示实验中用所挂钩码的重量作为细线对小车的拉力F通过增加钩码的数量多次测量可得小车运动的加速度a和所受拉力F的关系图象他们在轨道水平和倾斜的两种情况下分别做了实验得到了两条a﹣F图线如图b所示． 1图线填“①”或“②”是在轨道右侧抬高成为斜面情况下得到的 2在轨道水平时小车运动的阻力Ff＝N 3图b中拉力F较大时a﹣F图线明显弯曲产生误差．为避免此误差可采取的措施是． A．调整轨道的倾角在未挂钩码时使小车能在轨道上匀速运动 B．在增加钩码数量的同时在小车上增加砝码使钩码的总质量始终远小于小车的总质量 C．将无线力传感器捆绑在小车上再将细线连在力传感器上用力传感器读数代替钩码的重力 D．更换实验中使用的钩码规格采用质量较小的钩码进行上述实验．
如图所示在xOy平面内存在均匀大小随时间周期性变化的磁场和电场变化规律分别如图乙丙所示规定垂直纸面向里为磁感应强度的正方向沿y轴正方向电场强度为正．在t＝0时刻由原点O发射初速度大小为υ0方向沿y轴正方向的带负电粒子．已知u0t0B0粒子的比荷不计粒子的重力． 1t＝时求粒子的位置坐标 2若t＝5t0时粒子回到原点求0～5t0时间内粒子距x轴的最大距离 3若粒子能够回到原点求满足条件的所有E0值．
如图所示固定的水平光滑金属导轨间距为L左端接有阻值为R的电阻处在方向竖直磁感应强度为B的匀强磁场中质量为m的导体棒与固定弹簧相连放在导轨上导轨与导体棒的电阻均可忽略．初始时刻弹簧恰处于自然长度导体棒具有水平向右的初速度v0．在沿导轨往复运动的过程中导体棒始终与导轨垂直并保持良好接触． 1求初始时刻导体棒受到的安培力． 2若导体棒从初始时刻到速度第一次为零时弹簧的弹性势能为Ep则这一过程中安培力所做的功W1和电阻R上产生的焦耳热Q1分别为多少导体棒往复运动最终将静止于何处从导体棒开始运动直到最终静止的过程中电阻R上产生的焦耳热Q为多少
如图甲所示理想变压器原线圈匝数n1＝2200匝副线圈匝数n2＝100匝电流表电压表均可视为理想交流电表定值电阻R＝10Ω二极管D正向电阻等于零反向电阻无穷大．变压器原线圈接人如图乙所示的交流电压下列说法正确的是
如图所示一端封闭内径均匀的玻璃管长为L＝1.000m中间有h＝0.150m的水银柱将一部分空气封闭在管内水平放置时A端空气柱的长度LA＝0.400m．把玻璃管在竖直平面内缓慢倒转到开口竖直向下后再把开口端B缓慢插入水银槽内直到A端空气柱的长度为0.375m且再次处于平衡状态为止．已知外界大气压p0＝75cmHg在整个过程中温度保持不变．求最后平衡时玻璃管内B端空气柱的长度结果保留三位小数．
质量为M＝1kg的木板静止在粗糙水平面上木板与地面间的动摩擦因数为μ1在木板的左端放置一个质量为m＝1kg大小可忽略的铁块．铁块与木板间的动摩擦因数为μ2取g＝10m/s2．若在铁块右端施加一个从0开始增大的水平向右的力F假设木板足够长铁块受木板摩擦力Ff随拉力F的变化如图所示．则两个动摩擦因数的数值为
某同学设计了一个电磁推动加喷气推动的火箭发射模型其工作原理如图所示．竖直固定在绝缘底座上的两根长直光滑金属导轨间距为L导轨间加有垂直导轨平面向里的匀强磁场B．绝缘火箭支撑在导轨间总质量为m燃料室中的金属棒EF电阻为R通过电刷与导轨保持良好接触．引燃装置下方的推进剂迅速推动刚性金属棒CD电阻可忽略且和导轨接触良好沿导轨向上运动在棒EF中激励出强电流产生电磁推力加速火箭经过时间△t回路CDFE面积减少△S火箭刚好脱离导轨．当火箭脱离导轨时电阻R产生的焦耳热使燃料燃烧形成高温__气体燃烧室下方的可控喷气孔打开喷出燃气进一步加速火箭．不计空气阻力不计导轨的电阻 1求△t时间内棒EF中感应电流的平均值I及火箭脱离导轨时的速度V0 2若火箭总质量m＝10kg脱离导轨时的速度V0＝20m/s喷气孔在极短的时间内向下喷出质量m′＝2kg的燃气燃气相对喷气后火箭的速度为u＝100m/s．求喷气后火箭的速度Vl及喷气过程燃料释放的内能Q 3在第2问中若喷气孔将m′＝2kg的燃气分两次喷出每次喷出燃气的质量为m′/2燃气相对喷气后火箭的速度均为u＝100m/s求喷气后火箭的速度V2．
AboutsixyearsagoItookajobsomepeoplewouldconsideradreamjob.Atthetimeitwasconsideredasecurejobwithgreatbenefits.AstheyearspassedIrealizedIwasjustrepeatingeveryday.SoIdecidedtobeginbuildingmyownbusiness. Iknowwhatyouarethinking﹣there'snosecurityinthat!YeahIknow.IhaveheardthatandaboutonethousandotherreasonswhyIshouldhavecontinuedworkingattheregularjob.ButIdon'tregretmydecision.Iknowmanypeopleouttherealsowanttostarttheirownbusiness.Herearesomethingsyouneedtoknowbeforebreakingthemouldandleavingyour9﹣5toconcentratefull﹣timeonyourdreamThere'sneveraperfecttime.Somethingwillalwayscomeuptopreventyoudefer推迟yourdecisionchangeyourminddiscourageyouorsetyoubackabouttenyears. Havinganexperiencedandtrustedadviserisimportant.Why?Becauseifyoufindonewithasimilarthoughtprocessitislikelythattheyhavewalkedinthepathyouaretaking.Payattentiontotheiradviceasitcansaveyourheartache. Havingallthedetailsfiguredoutisimpossible.Therearesomanythingsyouhavetodobeforelaunchingoutintothedeep.Eitherwaytherearerisksinvolved.Youcanhaveallofyourinsecuritiessolvedandguesswhat!Somethingwillcomeuptomakeamessofeverything.Keepmovingon.Pressthroughit. Theclosertheyarethedeepertheystab.Notallofyourfriendswillcelebrateyourchange.Therewillbethosewhowouldratherdiscourageyouandtellyouhowyouwillnevermakeitbutalltheywouldhavetodoissupportyou.It'syourdream.It'syourresponsibility.Ifyouallowthewordsofotherstokeepyoufromityouweren'tsuitableforit. 25.Whydidtheauthordecidetostarthisownbusiness? A.Hegotfedupwiththeregularjob. B.Hewasencouragedbypeoplearoundhim. C.Hethoughthispreviousjobwasoutofdate. D.Hedidn'tmakegoodmoneyfromtheregularjob. 26.Whatdoestheauthormeanbybreakingthemouldinthesecondparagraph? A.Notobeyingtherulesatwork. B.Learningnewwaystodothejob. C.Gettingoutoftheoldworkplace. D.Improvingtheworkingenvironment. 27.Whichstatementwilltheauthoragreewith? A.Preparationisn'tthatimportantinstartingabusiness. B.Oneshouldjustdoitifhewantstostartabusiness. C.Moredetailsshouldbeconsideredtoreducerisks. D.Oneshouldtakeothers'wordsseriously. 28.What'stheauthor'spurposeinwritingthetext? A.Toexplainwhyhestartedhisownbusiness. B.Tomakehisbusinessknowntomorepeople. C.Togiveadvicetothosewantingtoworkforthemselves. D.Tocomparehavingaregularjobwithstartingabusiness.
如图所示在两个电荷量相等的正点电荷的电场中两电荷连线的中垂面上有一以连线中点O为圆心的圆AB为圆上对称的两点两点电荷连线的延长线上有一点C下列说法正确的是
某同学采用安阻法测电池a的电动势和内阻实验装置如图甲所示实验时多次改变电阻箱R的阻值记录电阻箱的阻值R和电流表的示数I得到R关系如图乙中的图线①所示重复上述实验方法测量电池b的电动势和内阻得到图乙中的图线②． 1由图线①可知电池a的电动势Ea＝V内阻ra＝Ω结果保留两位有效数字． 2若用同一定值电阻先后与电池a及电池b连接则两电池的输出功率PaPb选填“大于”“等于”或“小于”两电池的效率ηaηb选填“大于”“等于”或“小于”．
Capsaicin辣椒素canbeusedasmedicinetohelpreducepain.Itmayseemstrangethatwhatcausespainmightalsomakepaingoaway.Yetit'strue. TiborRohacsisamedicalresearcheratNewJerseyMedicalSchoolinNewark.Herecentlystudiedhowcapsaicinworkstoreducepain.ResearchersalreadyknewthatwhencapsaicinturnsontheTRPV1proteinit'sliketurningonabrightlight.Wheneverthelightisonthepersonexperiencespain.Rohacsandhiscolleaguesthendiscoveredachemicalchainreactionthatlatersilencesthispain.HesaysThelightshinessobrightlythatafterawhilethebulbburnsout.ThentheTRPV1proteincan'tturnbackonagain.Whenthishappensthebrainnolongerfindsoutaboutthefeelingofpain. Thehumanbodyisgoodatrepairingitselfhowever.Eventuallythepainwillfixthispainsystemandcanonceagainsendpainalerts警报tothebrain.HoweveriftheTRPV1proteinisactivated激活oftenthepainsystemmaynotgetachancetorepairitselfintime.Thepersonwillonlyfeeldiscomfortorburningatfirst.Thenheorshewillexperiencerelieffromothertypesofpain.Forexamplepeoplewitharthritisregularlyhavepainintheirfingerskneeshipsorotherjoints.Rubbingacreamcontainingcapsaicinontothepainfulareamayburnatfirst.Afterawhilehowevertheareawillbecomenumb. Rohacswarnsthatcapsaicincreamsdon'tseemtogetdeeplyenoughintotheskintototallyremovepain.Hesaysotherresearchersarecurrentlytestingcapsaicinbandagesorinjections.Theywouldlikelydoabetterjobathaltingpain.Unfortunatelytheytendtohurtalotmorethanacream﹣atleastinthebeginning.Someonewhocantoughoutthediscomforthowevercouldfeelnopaininthefollowingseveralweeksnothours. 32.WhathappenstothepersonwhentheTRPV1proteinisturnedon? A.Heloseshissenses. B.Hesuffersphysicalpains. C.Heslightlysensesdiscomfort. D.Hegetsusedtothefeelingofpain. 33.Whenmaythepainsystemnotrecover? A.WhentheTRPV1proteinburnsout. B.Whenthebraincannotreceivepainalerts. C.WhentheTRPV1proteinisturnedonfrequently. D.Whendifferenttypesofpainoccuratthesametime. 34.Whatistheproblemofcapsaicincreamswhentheyareusedtoreducepain? A.Theyarenotveryeffective. B.Theycauseburnsintheskin. C.Theycausetoomuchdiscomfort. D.Theycanstoppainforjustseveralweeks. 35.Whatdoestheunderlinedwordhaltinginthelastparagraphmean? A.Finding.B.Feeling.C.Hiding.D.Stopping.
如图所示水平面内ab和cd是两条平行放置的足够长直粗糙金属导轨MN和MN是两根用细线连接的金属杆其质量分别为m和2m两杆与导轨的动摩擦因数均为μ．开始时水平外力F作用在杆MN上使两杆以速度υ0水平向右匀速运动．两杆的总电阻为R导轨间距为d整个装置处在磁感应强度为B的匀强磁场中磁场方向与导轨所在平面垂直导轨电阻可忽略重力加速度为g．在t＝0时刻将细线烧断保持外力F不变金属杆和导轨始终接触良好已知在t＝t0时刻后杆MN速度保持不变且在0～t0时间内两杆速度方向始终向右求 10～t0时间内任意时刻两杆的加速度大小之比 2t0时刻两杆各自的速度 30～t0时间内两杆各自的位移．
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