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如图所示，在水平向右的匀强电场中有一绝缘斜面，斜面上有一带电金属块沿斜面滑下，已知在金属块滑下的过程中动能增加了12J，金属块克服摩擦力做功8J，重力做功24J，则以下判断正确的是（ ）
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高三下学期物理《》真题及答案
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如图所示斜面体固定在水平面上斜面粗糙.一带正电的绝缘物体自斜面上端由静止释放物体由顶端滑到底端所用的
在物体运动所在空间加竖直向下的匀强电场
在物体运动所在空间加水平向右的匀强电场
在物体运动所在空间加垂直纸面向里的匀强磁场
在物体运动所在空间加重直纸面向外的匀强磁场
水平地面上有一个倾角为θ的斜面其表面绝缘一个带正电的滑块放在斜面上两物体均处于静止状态如图所示当加上
滑块与斜面间的摩擦力一定变大
斜面体与地面间的摩擦力可能不变
滑块对斜面的压力一定变大
斜面体对地面的压力一定变大
如图所示在绝缘的斜面上方存在着沿水平向右的匀强电场一带电金属块由静止开始沿斜面滑到底端已知在金属块下
金属块带正电荷
电场力做功0.2J
金属块的机械能减少1.2J
金属块的电势能增加0.2J
如图所示倾角为30°的粗糙绝缘斜面固定在水平地面上整个装置处在垂直斜面向上的匀强电场之中一质量为m电
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动
金属块带负电荷
金属块克服电场力做功8.0J
金属块的机械能减少12J
金属块的电势能减少4.0J
带负电的小物体A.放在倾角为θsinθ＝0.6的绝缘斜面上整个斜面处于范围足够大方向水平向右的匀强电
一个绝缘斜面与水平面的夹角为a放在水平向右的匀强电场中如图所示.一个带电量为q质量为m的小物体在斜面
水平地面上有一个倾角为θ的斜面其表面绝缘另一个带正电的滑块放在斜面上两物体均处于静止状态如图所示当加
滑块与斜面间的摩擦力一定变大
斜面体与地面间的摩擦力可能不变
滑块对斜面的压力一定变大
斜面体对地面的压力一定变大
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能
金属块带负电荷
金属块克服电场力做功8.0J
金属块的机械能减少12J
金属块的电势能减少4.0J
水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能增加了12
金属块带负电荷
金属块克服电场力做功8J.
金属块的电势能减少4 J
金属块的机械能减少12J.
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能
金属块带负电荷
金属块克服电场力做功8.0J.
金属块的电势能减少4.0J.
金属块的机械能减少12J.
如图所示倾角为30°的粗糙绝缘斜面固定在水平地面上整个装置处在垂直斜面向上的匀强电场之中一质量为m电
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能
金属块带负电荷
金属块克服电场力做功8.0J
金属块的机械能减少12J
金属块的电势能减少4.0J
如图所示光滑绝缘斜面倾角为37°一带有正电的小物块质量为m电荷量为q置于斜面上当沿水平方向加有如图所
如图所示在绝缘的斜面上方存在着沿水平向右的匀强电场一带电金属块由静止开始沿斜面滑到底端已知在金属块下
金属块带正电荷
电场力做正功0.2J
金属块的机械能减少1.2J
金属块的电势能增加0.2J
如图所示倾角为长度为L.的光滑绝缘斜面上一个带正电荷的小物体质量为m带电量为q置于斜面顶端当沿水平向
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能
金属块带负电荷
金属块克服电场力做功8.OJ
金属块的电势能减少4.OJ
金属块的机械能减少12J.
如图所示在水平向右的匀强电场中有一绝缘斜面斜面上有一带电金属块沿斜面滑下已知在金属块滑下的过程中动能
金属块带负电荷
金属块克服电场力做功8.0J
金属块的机械能减少12J
金属块的电势能减少4.0J
如图所示一带电量为+q质量为m的小物块处于倾角为370的光滑斜面上当整个装置置于一水平向右的匀强电场
带负电的小物体A放在倾角为的绝缘斜面上.整个斜面处于范围足够大方向水平向右的匀强电场中如图所示物体A
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Wespendsomuchtimewaitingtobelovedhopinglovewillfindusandlookingforthatspeciallove.Unfortunatelythat'snotusuallyhowlifeworks.Tobelovedyoushouldloveandrespectyourselfasmuchasyoudoothers.Inordertolovesomeoneyoushouldloveyourself. ●Stopcomparingyourselftoothers.1.Weallhavedifferentgifts.Whenyoucompareyourselftoothersforwhattheyhavewhetheritisacarahouseorajobitmakesyoufeelbadaboutyourself.Reallybegratefulabouteverythingyouhave.Gratitudekeepsyourheartopentolove. ●Practicereceivinglove.Totrulyloveistobeabletoreceiveit.Whensomeonelovesyoudoessomekinddeedstoyouorsayskindwordsacceptit.2.Knowthatyouareworthyoflove.Itisimportanttoacceptagiftoflovebyothers.Yougiveyourselfachancetolearnmoreaboutyourselfthatyouarelovable.3. ●4.Writeaboutyourexperiencesgoodandbad.Whenyouwritedowngoodexperiencesallowyourselftofeelthosefeelings.Whenyourememberbadexperiencesallowyourselftofeelself﹣compassion.Compassionisnotself﹣pitybutratherwillingnesstoacceptone'sownpainandregret. ●Stoptryingtobeperfect.Stopblamingyourselfforbeinglessthanperfect.5.Justfollowallthestepsaboveanddon'tletanyone'sexpectationsofyouputanypressureonyou. A.Keepadiary. B.Appreciateyourself. C.Everyoneontheearthisunique. D.Dosomethinginreturnforhimorher. E.Yougivesomeoneajoyofgivingbylovingyou. F.Allowyourselftofeelthelovethathascomeyourway. G.AlwaysdoyourbestbutnotreachingperfectionisNOTfailure.
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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. LastyearwhenIwastryingtodecideiftostudyoverseasItalkedtomyfriend.ThiswasthebetterthingIcouldhavedone.ThiswasabigdecisionformebecauseIhadeverbeenoverseasonmyownandIwasnotsureifIcoulddoit.Shehadstudiedoverseaspreviousyear.ShetoldmeaboutthechallengesandopportunityImightcomeacrossandhelpmemaketherightdecision.Iwentanditwasamazed. WheneverIfacewithanimportantdecisionIseekadvicefromanother.InthiswayIamwell﹣informedbuthavethebenefitoftheirideasandexperiences.
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TheVanGoghMuseuminAmsterdamhaswelcomedhometwopaintingsbytheDutchmastermorethan14yearsaftertheywereripped抢offthemuseumswallinanighttimetheft.MuseumdirectorAxelRuegercalledtheirreturnoneofthemostspecialdaysinthehistoryofthemuseum. ThepaintingswerediscoveredlastyearbyItalianpolicewhiletheyweresearchingthesuspectedItaliancriminalsfarmhousenearNaplesforevidenceofdrugdealing.Thetwopaintingswerewrappedincottonsheets.Theywerestuffedinaboxandhiddenbehindawallinatoiletwhentheywerefound. Thepaintingswereconsideredamongtheartworksmostsearchedforintheworld.AfteryearsindarknesstheycannowshineagainTheyarebackondisplayatthemuseumbeforebeingtakentotheconservationstudioforrepairs.Fortunatelytheysufferedremarkablylittledamageasthieveswhohadclimbedupaladderandbrokenawindowtogetintothemuseumin2004rippedthemoutoftheirframes. Itisnotonlyasurprisethattheworkshavebeenrecoveredbutit'sevenmoresurprisingtheyareinrelativelyunharmedcondition.Ruegersaid. ThemuseumdirectorwasonvacationwhenthecallcamelastyearfromItalianauthoritieswhobelievedtheyhadrecoveredthepaintings.Hedidn'tcelebraterightaway.He'dhadcallslikethisbefore. Iwashopefulbutalsoalittlehesitant.Overtheseyearswehadsomanyoccasionswhenpeoplephoneduscontactedusclaimingthattheyknewsomethingaboutthewhereabouts下落oftheworksandeachtimeitwasfalsethetracewentcoldhesaid.So…thewayhasbeentillofdisappointment.ButmuseumexpertssenttoItalytochecktheauthenticity真实性oftheworksquicklyturnedRueger'sdoubtsintodelight. RuegersaidthepaintingsarenowbackpermanentlyatthemuseumwhichishometodozensofworksbyVanGogh.I'mveryconfidentthateverythingissafeinthemuseumfromnowonhesaid. 1Howwerethestolenpaintingsfound. A.Thepolicefoundthembyaccident B.Thearrestedthievesgaveinformation C.Somedrugdealersofferedclues D.Thepoliceknewthehiddenplace 2WhatsurprisedRuegermostaboutthelostpaintings? A.Theywerestolenatnight. B.Theywerefoundatlast C.Theysufferedlittledamage D.Thesearchtook14years 3WhenRuegergotthecallfromItalianauthoritieshe. A.quiteexcited B.feltquiterelieved C.plannedtocelebrate D.doubtedthenews 4WhatdoesitprobablymeanwhenRuegersaysthetracewentcoldinthe6thparagraph? A.Ruegergraduallylostinterestinthesearch B.Thenumberoffalsecallswasgreatlyreduced C.Ruegerfeltcoldbecauseoftoomanyfalsecalls D.Thechancetofindthepaintingsbecameslim
Organicfoodisverypopularthesedaysbutcanalsobeveryexpensive.Parentsofyoungchildrenandevensomepetownerswillpayhighprices1organicfoodiftheythinkit'shealthierthannon﹣organicfood.Butmanyothersthinkorganicfoodisjust2wasteofmoney. Thereisonemain3differbetweenorganicandnon﹣organicfood.Organicfarmsdonotuseagriculturalchemicalssuchaspesticides杀虫剂thatstopinsectsfromdamagingcrops. Inmany4countryfoodsthatclaimtobeorganicmusthavespeciallabelsthatguaranteethey6groworganically. Somepeoplethinkorganicalsomeanslocallygrownand6originalthiswastrue.Atfirstonlysmallcompaniesproducedtheseproducts.Butlaterbigfoodcompaniesalsobegansellingorganicproducts.Smallorganicfoodcompaniesfounditdifficult7competewiththesebigcompaniesandmanydidn'tstayinbusinessmuch8long. Manyfarmersandconsumersbelieveorganicfoodissaferandmorenutritious.Theythinkagriculturalchemicalscancauseseriousillnesseslikecancer9thereisn'tmuchevidenceprovingthisistrue.Howeverrecentstudieshaveshownthateatingorganically﹣gownproduce10reduceyourchancesofdevelopingheartdisease.Thereforeweshouldbebettersafethansorrywhenitcomestowhatweeat.
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刪除或修改. 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. Rosedevelopedastrangeseriousdiseaselastyear.Herpoorlyfamilycouldn'tpaysomuchmoneyforhertreatment.IntheafternoonofFebruary28ththeStudentsUnioninourschoolholdsanactivitytoraisesomemoneyforher.Althoughitwasalittlebitcoldthatday.manyteachersorstudentscametotheplayground.Theyputtheirmoneyinthecollectionbox.whichwasmadeofbysomestudents.WhotouchedusmostwasthatsomestudentsdonatedallourluckymoneytoRose.Finallyweraised10000yuanintotal.WhenwesentthemoneytoRose'shousefollowingdayRosetogetherwithherparentswasverygrateful.WithtearinhereyesRosesaidshewouldrepaythosewhohadhelpedherafterrecoveredfromherillness.
如图在直线坐标系xOy中从原点处向+y方向同时发射出大量比荷为＝1.0×104C/kg的带负电粒子粒子的初速度大小广泛分布于零到v0＝1.0×104m/s之间．已知这些粒子此后所经磁场的磁感应强度大小为B＝1.0T方向垂直于纸面所有粒子都沿+x方向经过b区域都通过点M30且沿y轴负方向．不计粒子的重力及粒子间的相互作用． 1判断磁场方向 2求速度为1.0×104m/s的粒子从O点运动到M点所用的时间 3通过计算求出符合要求的磁场范围的最小面积．
1某实验小组要对未知电阻Rx进行测量．他们先用多用电表欧姆档进行粗测若多用电表的电阻档有三个倍率先用×10档测量电阻Rx时操作步骤正确发现表头指针向右偏转角度过大为了较准确地进行测量应换到档填“×1”或“×100”．换档后应先填缺少的步骤之后用表笔连接待测电阻进行测量由表盘刻度读得该电阻的阻值是Ω． 2为准确测量该电阻阻值备有以下器材 A．电源电动势约3V内阻未知 B．电压表量程3V内阻无穷大 C．电阻箱最大阻值99.9Ω D．电键单刀单掷开关2个导线若干 该同学进行了如下操作 首先断开电键S2闭合电键S1调节电阻箱使电压表有一合适的读数U记下此时电阻箱的阻值R1接着闭合电键S2调节电阻箱使电压表读数仍为U记下此时电阻箱的阻值R2由此测得电阻Rx＝． 3测出电阻后该同学发现此电路还可以测出电源电动势E和内阻r．闭合电键S1S2调节电阻箱R读出多组R和U的数值并作﹣图象如图2所示该图线斜率为k纵轴截距为a．由此得出电源电动势E＝内阻r＝．
如图所示理想变压器原线圈和副线圈上接有阻值均为R的电阻R1R2原线圈接电压有效值为U的交流电源．现通过滑片P改变原线圈的匝数使原线圈和副线圈接人电路的匝数分别为n1n2则下列说法正确的是
STOCKHOLM.Oct.2Xinhuanet.comThe2018NobelPrizeinPhysicshasbeenawardedtothreescientistsworkingthefieldoflaserphysicstheRoyalSwedishAcademyofSciencesannouncedhereonTuesday. HalfoftheawardforgroundbreakinginventionsinthefieldoflaserphysicswenttoAmericanArthurAshkinandtheotherhalfwasawardedjointlytoFrenchmanGerardAlbertMourouandCanadianDonnaStrickland. Stricklandsaidinatelephoneinterviewwiththeacademyatapressconferencethatshewashappyandsurprisedtobereceivingtheprize.Commentingonherachievementssheemphasizedhowshetriestothinkoutsideofthebox. Ashkininventedopticaltweezers光学镊子thatgrabparticlesatomsvirusesandotherlivingcellswiththeirlaserbeamfingers.ThisnewtoolallowedAshkintorealizeanolddreamofsciencefictionusingtheradiationpressureoflighttomovephysicalobjects.Hesucceededingettinglaserlighttopushsmallparticlestowardsthecenterofthebeamandtoholdthemthere.accordingtothestatement. MourouandStricklandpavedthewayfortheshortestandmostintenselaserpulses激光脉冲evercreatedbymankind.Theysucceededincreatingultrashorthigh﹣intensitylaserpulseswithoutdestroyingtheamplifying放大的material.Theirrevolutionaryarticlewaspublishedin1985andwasthefoundationofStrickland'sdoctoralarticle. StricklandandMourou'snewlyinventedtechniquecalledCPAsoonbecamestandardforhigh﹣intensitylasers.Itsusesincludethemillionsofcorrectiveeyesurgeriesthatareconductedeveryyearusingthesharpestoflaserbeams.Thestatementsaidtherearestillinnumerableareasofapplicationthathavenotyetbeencompletelyexplored. Ithinkit'sreallynicethatDonnaStricklandasafemalescientistgottheprizethisyear.Andit'salsoagoodsignaltoyoungpeoplethatyoucandosomethingveryimportantveryearlyinyourcareerEvaLindrothemphasizedwhoisamemberoftheClassforPhysicsattheRoyalSwedishAcademyofSciences. IhopemorefemalescientistscanwinNobelscienceprizesinfuture.Therearemoreandmorewomenscientists.soIthinkitmaledominancewillchangeandmorefemalescientistsareleadingresearchgroupsandplayingabiggerroleLindrothadded. 1WhatdoesStricklandmeanbysayingtriestothinkoutsideofthebox? A.ShehasneverexpectedtoreceivetheNobelPrize B.Shehastakengreatpainstogettheachievement. C.HerachievementismainlyduetoherpartnerMourou D.Shealwaysthinksofcreativewaysofdoingresearch. 2Whatcanweknowabouttheinventionsoflaserphysics? A.Itwilltakealongtimetoputthemintouse. B.Theywillmakegreatcontributionstoeyeoperations. C.Theyareaimedtorealizeanolddreamofsciencefiction. D.MourouandStrickland'sinventiongrewoutofStrickland'sdoctoralarticle 3Whatcanweinferfromthepassage? A.StricklandisthefirstfemalescientisttowintheNobelPrize B.Thethreescientistsawardedarejointinventorsoflaserphysics CStrickland'ssuccessmeansfarbeyondtheinventedtechniqueitself D.Maledominancewillchangetheleadingpositionoffemalescientists 4Whatisthemainideaofthepassage? A.Laserphysicsisbeingusedinalotofareas B.FemalescientistswillwinmoreNobelPrizes C.Threescientistsshare2018NobelPrizeinPhysics D.Thewinnersaregoodexamplestotheyoungpeople.
如图所示为xOy平面直角坐标系在x＝a处有一平行于y轴的直线MN在x＝4a处放置一平行于y轴的荧光屏荧光屏与x轴交点为Q在第一象限内直线MN与荧光屏之间存在沿y轴负方向的匀强电场．原点O处放置一带电粒子发射装置它可以连续不断地发射同种初速度大小为v0的带正电粒子调节坐标原点处的带电粒子发射装置使其在xOy平面内沿不同方向将带电粒子射入第一象限速度与x轴正方向间的夹角为0≤θ≤．若在第一象限内直线MN的左侧加一垂直xOy平面向外的匀强磁场这些带电粒子穿过该磁场后都能垂直直线MⅣ进入电场．已知匀强磁场的磁感应强度大小为B带电粒子的比荷＝电场强度大小E＝Bv0不计带电粒子重力求 1粒子从发射到到达荧光屏的最长时间 2符合条件的磁场区域的最小面积 3粒子打到荧光屏上距Q点的最远距离．
It'sabighammertocrackanut.Thisishowoneangryparentdescribedtherecentcrackdown严厉的打击byLondonpoliceonparentswhodroptheirkidsoffatschoolbycar.Yesyoureadthatcorrectly﹣theverymode模式oftransportationthatmanyAmericanschoolsinsististheonlysafewaytodeliverkidstoschoolisnowconsideredillegalintheUK. ThedecisiontofineanyvehiclesseendroppingofforpickingupkidswithinaparticularzoneofeastLondoncomesfromcitycouncilors'议员long﹣termeffortstomaketheareasaferandlesscrowded.Theysaythey'vebeentryingforyearstoencouragereasonableparkingbutinvain.Neighborhoodresidentscomplainfrequentlyabouttheirdrivewaysbeingblockedbyillegallyparkedcarsfor15minutesormoreoftenwhilethey'retryingtogettoworkandthestreetsarelongovercrowded. Nowtheruleshavechanged.Someparentsareangry.Angieisamotherwhomadethebighammercommentandsaysthecrackdowniswayoverthetop.Thenearestdrop﹣offpointforhersix﹣year﹣oldisnowafive﹣minutewalkfromtheschool.Othersarehappywiththedecisionseverethoughitmayseem. CouncilorJasonFrostsaidTraffichasbeenclearlyreducedandmorechildrenarenowwalkingtoschoolwhichisagreatoutcome.Iwouldratherhavecomplaintsthatweareslightlyinconveniencingparentsthanhearthatachildhadbeenseriouslyinjuredbecausenothingwasdone. Iwitnessdailythechaoscreatedbythesein﹣towndriverswhenIwalkmyownkidstoschool.There'saparkinglotcrowdedwithvehiclesandaslow﹣movingtrainofcarsmovingincirclesmanyfillingtheairwithharmfulsmoke.Meanwhiletheconversationsaroundoverweightchildrenandtheimportanceofdailyphysicalactivitiescontinuetostandoutinschools. 1WhyisAngieopposedtothenewrule? A.SheisoftenfinedbyLondonpolice. B.Shewillloseherjobasaschooldriver. C.ShehasadaptedtotheAmericanpractice. D.Shethinksitaddsinconveniencetoherkid. 2WhathasledtothenewrulebeingmadeaccoringtoJasonFrost? A.residents'complaints. B.students'healthproblem. C.safetyconcern. D.airpollution. 3Whatcanbeseenafterthecrackdowniscarriedout? A.Lessdailychaos. B.Supportfromallpeople. C.Moreoverweightchildren. D.Complaintsfromneighbors. 4Whatisthemainideaofthetext? A.Parentsattempttoresistaschoolrule. B.Londonpolicecausewidespreadanger. C.Americanschoolscaremoreaboutkids'safety. D.Differentvoicesareheardonanewtrafficpolicy.
某玻璃材料制成的光学元件截面如图所示左边是半径为R的半圆右边是直角三角形CDE∠DCE＝60°．A点发出一细光束从B点射入元件后与AO平行O为半圆的圆心CD为直径AO与CD垂直．已知玻璃的折射率为B点到AO的距离为R光在真空中的光速为c．求 i入射光线AB与AO夹角α ii光线从B点射入元件到第一次射出元件所需的时间．
某厂家为了测试新款汽车的性能将两辆完全相同的汽车并排停在检测场的平直跑道上tl＝0时刻将两车同时启动通过车上的速度传感器描绘出了两车的速度随时间变化的规律图线如图所示．已知图象中两阴影部分的面积S2＞S1则下列说法正确的是
假定你是李华本来约好周六要带你的外国朋友Toby去看京剧PekingOpera可你要代表本班参加英文演讲大赛而不能赴约请你给他写封邮件表达歉意. 写作要点1.解释不能按时赴约的原因 2.重新安排时间并给他推荐一两个周末休闲活动. 注意1.词数100左右 2.可以适当增加细节以使行文连贯.
Exerciseisanimportantpartofkeepingahealthylifestyle.Fitnesstoolsandtipscanhelpindividualsdevelopanexerciseplanthatisnotonlysafebuthelpsthemtoworktowardacertaingoalsuchasweightlossorrunningamarathon. ConsultYourDoctor Beforebeginningtheweightlossorexerciseprogramitisbesttoconsultyourdoctortomakesurethatyouareinproperhealthandthattherearenopossibleconditionsthatcouldgetworsebyexercise.Askyourdoctortorecommendexercisesbasedonyourfitnesslevelthatwillhelpyouachieveyourgoals. SetGoalsandLimits Whenbeginningafitnessprogramitisimportanttostartoffslowandworktowardamoreadvancedgoal.Beginwithshort10﹣to20﹣minuteexerciseeachdaytoprepareyourbodyformoreactiveexercisesandtopreventinjury. DrinkPlentyofWater Duringexercisethebodylosesliquidfromsweatingthereforeitisimportanttodrinklotsofwaterbeforeduringandafterexercising.Expertsrecommenddrinkingwaterorsportsdrinksevery15to20minutesduringexerciseandmoreoftenduringmoreactiveexercises.Continuetodrinkwaterseveralhoursafterexercisingtorefillliquidsinthebody. ExerciseEquipment Exerciseequipmentsuchastreadmills跑步机exercisebikesandweightsisagreatwaytostayfitwhenonabusyscheduleoronrainydays.Beforeusingexerciseequipmentathomeorinthegymeducateyourselfontheproperuseofeachpiecetoavoidinjurytoyourselfordamagetotheequipment. TrackingTools Useoftoolssuchaspedometers计步器orheartratemonitorscanhelprecordcaloriesstepsandheartrate.Thesetoolscanhelpkeepdietersandathletesactiveandeagertoreachtheirhealthandfitnessgoals. 1What'sthemainpurposeofthepassage? A.Tointroducesomewaysofexercising. B.Tointroduceussomeexercisetipsandtools. C.Topersuadeustotakeexercisetokeepfit. D.Togiveusadviceonlosingweightbyexercise. 2WhichofthefollowingisTRUEaccordingtothepassage? A.Youcanloseweightortakeexerciseinpoorhealth. B.Treadmillsareonlyusedinthegymwhenitrains. C.Startingwithlongandviolentexercisemaycauseinjury. D.Youneedtodrinklotsofwateruntilyoufinishexercising. 3Howoftenshouldwedrinkwaterduringextremeactiveandviolentexercises? A.Every10minutes. B.Every15minutes. C.Every20minutes. D.Every30minutes.
如图所示两端封闭的粗细均匀且导热性能良好的玻璃管放置在水平桌面上玻璃管长度为3L单位cm玻璃管内由长度为L单位cm的水银柱将管内的理想气体分成左右两部分稳定时两部分气体长度相同左右两部分气体的压强均为HcmHg．现在外力作用下使玻璃管沿水平桌面向右做匀加速直线运动玻璃管中左侧的气柱长度变为原来的一半重力加速度为g求玻璃管运动的加速度a的大小．
Beth.justonemoresaidmynurseMary.Ihadjustmadeanothersit﹣up仰卧起坐red﹣facedand1andthenfellbackontothemat.Maryleanedovermewaitingformeto2myarmandgiveherfive击掌相庆. Icant.Isaid.Givemeaminute.IwonderedagainhowIhadgottentothis3.Fivesit﹣ups?Icouldbarely4itwithouthavingtorestnow.Whathad5thegirlwhooncecouldevenswimandrun?Yourformerselfis6.Marysaid.Whoeveryouwereconcentrateonbeingwhoyou'renow.ButIcouldn't.Ihatedthediseasethatcausedmy7.Itevenmadewalkingupstairsahardthing. WithasighIpushedupwithonearmand8drewmyselfintoaseatedposition.I9outandgaveMaryahighfive.ShesmiledatthefactthatIwasstill10IhatewhoI'mnowIsaid.Beth.shesaidgently.Fitnessisn'tan11.Youjustneedtocompareyourselfwithyourself.Ifyoucoulddofivesit﹣upstodaydosixtomorrow.Iknewwhatshesaidwasto12me. Anywaythatdaywe13thesessionquitewellandItookher14toheartinthecomingdays.Onhotdays.ashort15couldmakemesweatasifIhadgoneforalongjog.YeteverytimeIwantedto16IsaidJustonemore. NowthatI'veadjustedtolife.thererefewdayswhenI'm17withhowmuchIcantdo.OccasionallywhenIwatchsomeonedanceorrunandcan'thelpbut18myselftohimorherI'llthinkofthewordsthatIonlyneedtothinkaboutmyself﹣imaynotbeas19asothersbutI'mstill20todoingjustonemoreofwhateverIneedtodo. 1A.exhausted B.encouraged C.excited D.amazed 2A.drop B.bend C.wave D.lift 3A.answer B.area C.point D.truth 4A.get B.make C.resist D.take 5A.happenedto B.broughtup C.letdown Dsettleddown 6A.subjective B.tough C.gone D.sympathetic 7A.regret B.weakness C.shame D.unemployment 8A.eventually B.suddenly C.actually D.seldom 9A.worked Bslipped C.stepped Dreached 10A.striking B.waiting C.struggling D.learning 11A.achievement B.competition C.advantage D.goal 12A.treat B.believe C.embarrass D.push 13A.gotonwith B.madeupfor C.putaside D.figuredout 14A.warning Bcommand C.advice D.blame 15A.break B.sleep C.speech D.walk 16A.run Bresign C.hurt D.quit 17A.stuck B.connected C.filled D.occupied 18A.add B.compare C.relate D.attach 19A.outgoing B.brave C.strong D.optimistic 20A.equal Bcommitted C.close D.open
TimeOutNewYorkyourultimateguidetolifeinthecityhelpsyoudiscoverthebesteventsandthingstodoinMarch Mar3﹣5.NewYorkInternationalLiteraryFestival TheliteraryeventchampionofNewYorkisback!Manybest﹣sellingauthorsaresettoappearatthisyearsfestivalincludingtheaward﹣winningwriterAmyTanTheJoyLuckClubthefilmversionofthenovelstarringMichelleYeohInternetbusinessexpertwriterDuncanClarkAlibabaTheHouseThatJackMaBuilttheAnthillfounderAlecAshWishLanternsandmanymore.Staytunedforourfullfestivalpreviewandauthorfeatures Mar3﹣15varioustimes20dollarsor35dollarsforliterarylunches.Glam. UntilMar16VivienneWestwood﹣GetaLife Thewell﹣knownfashiondesigneristhesubjectofthiscrossoverexhibitionofAmericancontemporaryartandeco﹣friendlyfashioninspiredbyWestwood'sstrongattitudetowardsaclimaterevolutionParticipatingartistsalsoincludeAdamLawryandJillSmith UntilMarch16freeentry.ChiK/lArtMuseum Mar17DogDaySaturdays OnthethirdSaturdayofthemonthTheRooster13thStreetthrowsabackyardPartywheredogsarewelcome.Therewillbefreehotdogs.5dollarsFlyingDogBeersanddogtreatsforthelittlebuddiesDonationswillalsobecollectedforlocalanimalrescuegroupBestFriendsAmerica Mar173﹣5P.m.15dollars.TheRooster13thStreet Mar28﹣29MomtoMomSale Sellorstockuponclothestoysbooksstrollersandotherfamilygoodsatthistwice﹣a﹣yearmarketorganizedbyNewYorkmotherSellerswillcontribute15percentofalltheirprofittoHearttoHeartComeandpickupsomeusefulstuffforyourfamily. Mar.28﹣292﹣6pmTues.10a.m.﹣2p.mWed.freeentry.NewYorkRacquerClub﹣clubhouse 1WhowillpossiblyturnupatGlamonMarch10th? A.MichelleYeoh B.JackMa C.AlecAsh D.AdamLawry 2Whicheventmightinterestthosewhocareabouttheenvironment? A.NewYorkInternationalLiteraryFestival B.VivienneWestwoodGetaLife C.DogDaySaturdays D.MomtoMomSale 3WhatdotheeventsDogDaySaturdaysandMomtoMomSalehaveincommon? A.Participantscansupportcharitywork. B.Participantsareadmittedfreeofcharge C.TheyareorganizedannuallyinNewYork D.Theytakeplaceatthesametime
An18﹣year﹣oldstudentwasstrugglingtopayhistuitionfees.Asanorphanhedidn'tknowwhomto1toformoney.SohedecidedtohostamusicalconcertatStandfordUniversityto2moneyforhiseducation. Hereachedouttothegreat3IgnacyJanPaderewski.Paderewski4afeeofUS﹩2000forthepianoconcert.Adealwas5.Andtheboybeganto6tomaketheconcertasuccess. The7dayarrived.PaderewskiperformedatStandfordUniversity.But8theboyhadn'tmanagedtosellenoughtickets.Thetotal9wasonlyUS1600.DisappointedhewenttoPaderewskiand10hisplight困境.HegavePaderewskitheentireUS﹩1600plusachequeforthe11ofUS﹩400.Theboypromisedto12themoneyassoonaspossible.Paderewskitoreupthecheque13theUS﹩1600andtoldtheboy14themoneyforyourtuitionfeesandjustgivemewhateverisleft.Theboywasvery15andthankedhimsincerely. Itwasasmall16ofkindness.Weallcomeacross17likethisinourlives.AndmostofusonlythinkIfIhelpedthemwhatwouldhappentome?Thetruly18peoplewouldthinkIfIdon'thelpthemwhatwouldhappentothem?Theydontdoit19somethinginreturn.Theydoitbecausetheyfeelit'sthe20thingtodo. 1A.turn B.apply C.relate D.refer 2A.borrow B.raise C.make D.beg 3A.pianist B.violinist C.drummer D.singer 4A.promised B.demanded C.suggested D.charged 5A.drafted B.recorded C.struck D.postponed 6A.play B.work C.practice D.cooperate 7A.bright B.easy C.warm D.big 8A.unfortunately B.unfaithfully C.unwillingly D.uncertainly 9A.charge B.collection C.gain D.cost 10A.analysed B.announced C.consulted D.explained 11A.interest B.price C.balance D.income 12A.giveback B.putaway C.takedown D.leaveout 13A.hid B.divided C.cast D.returned 14A.Get B.Accept C.Keep D.Withdraw 15A.surprised B.panicked C.embarrassed D.terrified 16A.choice B.act C.habit D.wish 17A.conversations B.examples C.situations D.processes 18A.brave B.smart C.great D.curious 19A.accepting B.predicting C.charging D.expecting 20A.good B.wise C.real D.right
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