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已知椭圆的左、右顶点分别为A,B,长轴长为4,离心率为.过右焦点F的直线l交椭圆E于C,D两点(均不与A,B重合),记直线AC,BD的斜率分别为k1,k2. (Ⅰ)求椭圆E的方程; (Ⅱ)是否存...
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设椭圆的左右焦点分别为F1F2右顶点为A上定点为B已知 求椭圆的离心率
5.00分已知命题在平面直角坐标系xOy中椭圆△ABC的顶点B在椭圆上顶点AC分别为椭圆的左右焦点
设A.B.分别为椭圆=1a>b>0的左右顶点椭圆长半轴的长等于焦距且直线x=4是它的右准线.1求椭圆
已知椭圆C.的离心率与等轴双曲线的离心率互为倒数直线l:x-y+=0与以原点为圆心以椭圆C.的短半轴
如图设椭圆的中心为原点O.长轴在x轴上上顶点为A.左右焦点分别为F.1F.2线段OF1OF2的中点分
已知椭圆E=1a>b>0的离心率为其长轴长与短轴长的和等于6.1求椭圆E的方程2如图设椭圆E的上下顶
已知椭圆中心在原点焦点在x轴上离心率点F1F2分别为椭圆的左右焦点过右焦点F2且垂直于长轴的弦长为1
已知椭圆x2+=10
已知椭圆=1a>b>0的离心率为过焦点垂直长轴的弦长为3.1求椭圆的标准方程2过椭圆的右顶点作直线交
已知椭圆E=1a>b>0的离心率为其长轴长与短轴长的和等于6.1求椭圆E的方程2如图设椭圆E的上下顶
已知椭圆中心在原点焦点在x轴上长轴长等于12离心率为.Ⅰ求椭圆的标准方程Ⅱ过椭圆左顶点作直线l若动点
已知O为坐标原点F是椭圆C://的左焦点AB分别为C的左右顶点P为C上一点且PF⊥x轴过点A的直线
A
B
C
D
已知椭圆的离心率为长轴长为4M.为右顶点过右焦点F.的直线与椭圆交于A.B.两点直线AMBM与x=4
如图已知F1为椭圆的左焦点A.B.分别为椭圆的右顶点和上顶点P.为椭圆上的点.若PF1⊥F1APO∥
如图4椭圆的中心在坐标原点为左焦点分别为长轴和短轴上的一个顶点当时此类椭圆称为黄金椭圆.类比黄金椭圆
已知椭圆中心在原点焦点在x轴上长轴长等于12离心率为.1求椭圆的标准方程2过椭圆左顶点作直线l若动点
已知O为坐标原点F是椭圆C=1a>b>0的左焦点ABD分别为椭圆C的左右顶点和上顶点P为C上一点且
如图椭圆的中心在坐标原点F.为左焦点A.B.分别为长轴和短轴上的一个顶点当FB⊥AB时此类椭圆称为黄
已知椭圆C.+=1a>b>0的左右交点分别为F1F2且|F1F2|=4A.﹣是椭圆上一点.1求椭圆C
已知椭圆中心在原点焦点在x轴上长轴长等于12离心率为.Ⅰ求椭圆的标准方程Ⅱ过椭圆左顶点作直线l若动点
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PanamaCityPanama ForbeachvacationsthatgetyououtoftownandinviteyouandyourfamilytodiveintocultureconsideratriptoPanamaCity.Hereyouwillenjoybeachesandcityexploring.BookyourstayattheWestinPlayaBonitawhereyoucanbookaroomstartingat﹩222anight.TherearevariousprogramsincludingbeachOlympicsstargazing天体观察andSpanishlessons. JupiterFlorida Thisplaceoffersyouqualitytimeyoucanspendwithyourlovedones.BookyourstayatJupiterBeachResort&Spawithratesforafamilyoffourstartingat﹩207anight.Hereyoucanshootbasketsatthebasketballcourtstakeadipinthepoolorteachyourchildrenbeachyoga. SanDiegoCalifornia TheWestCoastisagreatspotforcheapbeachvacationssotellyourfamilytopacktheirbagsforavisittoSanDiego.Acheap﹩10UberridefromtheairportwillhaveyoupullinguptheKonaKaiResort&Spa.HereafamilyoffourcanstayinaDeluxeGuestRoomstartingat﹩159pernight.Yourkidscanpracticecannonballsatthepoolafteravisittotheworld﹣famousSanDiegoZoo. KiheiMauiHawaii ForWestCoasterswhoaregrowingboredwiththeirbackyardflytotheislandsofHawaii.StayattheAstonattheMauiBanyanwithachargeof﹩179anightforafamilyoffour.Hereyou'llwitnesssomeofthebestsunsetsofyourlifewhileyourkidssplash戏水inthePacificAndifyou'resetoncookingafancymealyou'llenjoysuitesthatcomewithafullkitchen. 1Whichofthefollowingchargesyouleastanight? A.TheAstonattheMauiBanyan. B.TheWestinPlayaBonita. C.TheKonaKaiResort&Spa. D.JupiterBeachResort&Spa. 2WhatcanyoudoattheAstonattheMauiBanyan? A.Admirebeautifulsunsets. B.Visitaworld﹣famouszoo. C.Observefantasticstars. D.Playsomebeachsports. 3Whatisthecommonfeatureofthefourdestinations? A.Theyallofferroomswithafullkitchen. B.Theyareallintendedforfamilytrips. C.Theyallpickupvisitorsfromtheairport. D.Theyallprovidebikeridingonthebeach.
15分NewYearinChineseeyesisafamilyreunion.Howeverinforeigners'eyesitisnotonlyakindofhomesicknessbutaspringmigration迁徙.Everyyear1seethelargestannualmassmigrationontheplanet2Onesixthoftheworld'spopulationtravelhometocelebrate3theirfamilies.Thatisaroundabillionpeople4make3.5billionjourneysina40﹣dayperiod.Meanwhileover250millionrailjoumeysaremadeacrossChinaduringthefestival. Lastyear5.6millionrailtickets5sellinasingleday.EverynewyearintheheartlandofindustrialChinathousandsuponthousandsofmotorcyclistsbravetheweatherandhittheroaddeterminedtomake6home. TheChineseNewYear7celebrateisalsoknownastheSpringFestival.Itlasts15 days.ItisthemainholidayoftheChinesecalendar.InmodemChina8searchforworkmanypeoplehavetomoveawayfromhome.Andtheywilltravelhometobewiththelovedones duringtheSpringFestival.InChineseNewYearmodemand9traditioncustomsare broughttogetherwhentheChinesecelebratetheSpringFestival.NowadaysnotonlydoesChinahavethe10fastgrowingmodemcitiesintheworldbutthelandscapesarealsotruly diverse.
10分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. Afamousfilmopenedacrossthecountrylastmonthwhichwasthebiggesthitofthesummer.LastSundaymyfamilywenttoseeafilm.Webookedticketsonadvance.Wewerearrivedatthecinemafifteenminutesearly.Wefounditwascrowdandpeopleweretalkingaboutthefilmexcited.Icouldn'twaitseemyfavoritestarJackwhoplaysacleversoldierinthefilm.It'safunfilmcombinedlotsofactionandsomehumorwithfeelingsforfriendandfamilies.Theywereallmovedbythewordsattheendofthefilm.Iwillkeepitinmindwhatmygreatcountryisalwaysbehindme.
如图所示设地球半径为R假设某地球卫星在距地球表面高度为h的圆形轨道Ⅰ上做匀速圆周运动运行周期为T到达轨道的A点时点火变轨进入椭圆轨道Ⅱ到达轨道的近地点B时再次点火进入近地轨道Ⅲ绕地做匀速圆周运动引力常量为G不考虑其他星球的影响则下列说法正确的是
15分ThemakeupofBritishfamilieshaschanged1rapidoverthelasttwohundredyears.Thetraditionalfamilystructure结构beforetheIndustrialRevolutionwastheextendedfamilyin2threegenerationslivedunderoneroof.Theearlytwentiethcenturysawthe3growofthenuclearfamily﹣parentsandasmallnumberof4childwouldformasinglefamily.InthelastthirtyyearshowevertheUK5seeabreakdownofthetypicalnuclearfamily. Increaseddivorcerateslatermarriageandamoveawayfrommarriagealtogetherhaveresulted6newformsoffamilydivorcedparentswilldevelopnewrelationshipsandtaketheirkidswiththem.Asurvey7conductbyresearchersshowsthatover50%ofkidsarenowborntoparentswhoarenotmarried. Someminoritycommunitiessticktotheextendedfamilystructureanditiscommon8findthatthreegenerationsarelivingtogetherinanIndianfamily.Theysaythatapartfromstrengtheningtraditionalfamilyties9canprovidesecurityforolderpeoplewhentheycannotworkanymore.Theybelievethatthephenomenonofotheroldpeoplelivingincarehomes10indicatethatmanyoldpeopleinthewidercommunityareabandonedintheiroldage.
8分Itmightsoundfunnybuthavingacertainroutineinthemorningoreveningwillhelpyoutogrowpersonallywithyourworkoutsandalsowithyourjobandlife.Whyisthat?Thehumansadaptprettywelltoroutinesandthatmakesusmoreefficientmeaningthatyoucansavealotoftimeandthatyourbodyalsocanrelaxbetterandfaster.ThisiswhatI'velearntfrommyownmorningroutines. Iformyselfalwayspreparemyfirstmealforthefollowingdayeveryevening.Itake300mlofwater30gramsofchiaseedsandacoupleoats燕麦andleavetheminaplasticcontainerinmyfridgeovernight.AllIhavetodointhemorningistoaddsomefreshberries. IalsohavemycupandmycoffeecapsulereadyandthefirstthingwhenIcomeoutoffthebathroomistoturnonthecoffeemachinewhileI'mgettingdressed.Gettingdressedisagoodpoint.Ihavealreadypreparedmyclothesforwork.SoIdon'tgetstuckinmydecisionwhetherIwanttowearthewhiteblackpurpleorblueblouse. AfterI'mdressedmycoffeeisreadyandwhileI'mquicklygettingmyhairandmake﹣updoneI'lldrinkmycoffee.Idon'tneedusuallylongerthan30﹣40minutesinthemorningtogetreadyandleavethehouse.Thishelpsmefirstlytosleepalittlebitlongerandsecondlynottobeinarushandbecalmfortheday. Somyfriendstrytoapplysomecertainroutinestoyourdayandyou'llseehowyourmindandyourbodywilladapttothemandyouhavemoreenergytofocusonimportantthings. 1Whatdoestheunderlinedwordthatinthefirstparagraphreferto? A.Aproblemwithacertainroutine. B.Thelinkbetweenroutinesandlife. C.Awayofhavingacertainroutine. D.Thebenefitofhavingroutines. 2Whatdoestheauthordothenightbeforeforhernextmorning? A.Shemakeshercoffee. B.Shedoesshoppingforbreakfast. C.Shegetsherclothesready. D.Sheaddssomeberriestothecontainer. 3Whatcanweknowabouttheauthorsmorningroutines? A.Theykeepherinhighspirits. B.Theygivehermoretimetorest. C.Theyhelpherfigureoutproblemsfaster. D.Theyimproveherabilitytohandlesituationsbetter. 4Whatistheauthor'spurposeinwritingthetext? A.Tohelppeopletofocusonimportantthings. B.Tointroducehowtoadapttoroutinesinlife. C.Toencouragepeopletohaveroutinesinlife. D.Toteachpeoplehowtorelaxthemselvesinlife.
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如图所示一条足够长且不可伸长的轻绳跨过光滑轻质定滑轮绳的右端与一质量为12kg的重物相连重物静止于地面上左侧有一质量为10kg的猴子从绳子的另一端沿绳子以大小为5m/s的加速度竖直向上爬取g=10m/s2则下列说法正确的是
乒乓球运动的高抛发球是由我国运动员刘玉成于1964年发明的后成为风世界乒兵球坛的一项发球技术.某运动员在一次练习发球时手掌张开且伸平将一质量为2.7g的乒乓球由静止开始竖直向上抛出抛出后向上运动的最大高度为2.45m若抛球过程手掌和球接触时间为5ms不计空气阻力则该过程中手掌对球的作用力大小约为
XYZW和R为原子序数依次增大的五种短周期主族元素.已知X元素的原子半径素周期表的所有元素中是最小的YR同主族且R原子的核电荷数是Y原子的核电荷数的2倍ZW原子的最外层电子数之和与YR原子的最外层电子数之和相等.下列有关说法中正确的是
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如图所示在一固定水平放置的闭合导体圆环正上方有一条形磁铁从静止开始下落下落过程中始终保持竖直方向起始高度为h最后落在水平地面上.若不计空气阻力重力加速度取g下列说法中正确的是
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G对羟基苯乙酸是合成某治疗高血压药物的中间体.一种由芳香烃A制备G的合成路线如图所示. 请回答下列问题 1A的名称为. 2试剂M是.B→C的反应类型是. 3E的结构简式为.F中含有官能团的名称是. 4写出D→E反应的化学方程式. 5H是G的同分异构体且满足下列条件①与FeCl3溶液发生显色反应②核磁共振氢谱有5组峰峰面积之比为12221.请写出3个符合条件的H的结构简式. 6苯甲酸可用于染料载体香料及增塑剂等的生产.参考题目中的有关信息设计由苯制备苯甲酸的合成路线无机试剂自选.
二环[100]丁烷是最简单的桥环化合物.下列关于该化合物的说法错误的是
如图所示在x=0处的质点O在垂直于x轴方向上做简谐运动形成沿x轴正方向传播的机械波.在t=0时刻质点O开始从平衡位置向上运动经0.4s第一次形成图示波形P是平衡位置为x=0.5m处的质点.①位于x=5m处的质点B第一次到达波峰位置时求位于x=2m处的质点A通过的总路程.②若从图示状态开始计时至少要经过多少时间PA两质点的位移y坐标才能相同
10分 ApologizingtheRightWaytoaFriend Whyareapologiessodifficult?Sayingyouaresorrycanbeoneofthemostdifficultthingsyoudo.Butweallmakemistakessoyou'llprobablyhaveanoccasionwhenyouneedtoapologize. Perhapsyouhadabigblowupandrealizedlateryoureactedpoorly.1Whateverthereasonapologizingcanhelpyoubothhealandmoveonfromthesituation. 2Firstyouacknowledgethatyoudidsomethingwrong.Withanapologyyoutakeresponsibilityforyouractionswhichallowsyourfriendtoforgiveyou.Secondanapologygivesyousincerityasafriend.3butthatdoesn'tmeanyoustillshouldn'tapologize. Nowwhatareelementsofaproperapology?4dependingonwhattheoffensewaswhereitwasdoneandwhoyouareapologizingto.Ingeneralagoodapologyshouldincludethefollowingarequestfortheirattentionanacknowledgmentofwhathappenedsincerityinadmittingyoudidsomethingwrongandthewords.I'msorryorIapologize. Herearethingsnevertosaywhenapologizing.Notethattheartofapologizinginvolvestakingresponsibility.Neverapologizeasawaytoshutsomeoneupwhentheyaresayingyouhurttheirfeelingsandyoudon'tthinkyoudid.5youshouldtalkthingsthroughwithyourfrienduntilyouseewhytheyarehurtorhowyoucameacross.You'llreallyneedtoself﹣reflectsoyoucanseethingsfromyourfriend'spointofview. A.Whenyoumakeyourapologyinperson B.Ifyoureallybelieveyoudidnothingwrong C.Apologiesbenefitfriendshipsinavarietyofways D.Thewayyouapologizeisgoingtobeslightlydifferent E.Ormaybeyoujustdidn'tshowsupportwhenyouneededto F.Apologizingtherightwayhowevermaytakealittlepractice G.Sometimesourpalsforgiveuseasilyfortheminorthingswedowrong
8分Haveyoueverheardofagritourismwhereyoucanexperiencefarmlife?IfnotDr.CindyAyers﹣ElliottwilltellyoutherealstoryofFootPrintFarms. TheoriginalconceptofbuildingFootPrintFarmswassimple.WhenAyers﹣Elliottreturnedtoherhometownaftergraduationshedidn'thavetolookanyfurtherthanherstate'salarminghealthstatisticstofindamission.Everywheresheturnedtherewerereportsofhighbloodpressurediabetesobesityandheartdisease.Theproblemwasalreadyidentified.explainsAyers﹣Elliott.ToomanyMississippianswereseriouslyunhealthyanditdidn'ttakeresearchtoseethat.Andmanyofthestate'sgreatesthealthchallengescoulddirectlyresultfrompoordiet. ThesedaysFootPrintFarmswhichstartedwithafewraisedbedsofherbsandvegetablesismakingfreshnaturallygrownfood.Whenspeakingofthekeytomysuccesstheco﹣opmodelworksbecausewesharetheworkandrewardsnotesAyers﹣Elliott.AperfectexampleistheWingfieldHighSchoolfootballteam.Toearnthemoneyforequipmentandotheritemsplayerscommittedtoworkingfivehoursaweekonthefarmandbytheendofthesummertheyhadproduced1000melonsandtheprofitsfromtheirsaleshelpedtobuyweightsT﹣shirtssweatsuitsandpregamemeals.Butthelessonstheylearnedabouttherewardsofhardworkandworkingtogethertoaccomplishsomethingwereevenmorevaluableproductsoftheirefforts. It'samodelthatcaneasilybelearnedinotherplacesandI'mlookingforwardtoseeingsomeofourcurrentpartnersdojustthat﹣﹣totakewhattheyhavelearnedhereandspinitoffinothercommunitiesAyers﹣Elliottremarks.Sheisnowlookingforwardtodevelopinganagritourismaspecttothefarmwherevisitorscanexperiencefarmlifelearnnewskillsandtakewiththemseedsofinspirationtheycansowintheirowncommunitieswhentheyreturnhome. 1WhatmadeAyers﹣ElliottsetupFootPrintFarms? A.Theproblemsfacedbylocalfarmers. B.Herfurtherresearchintoheartdisease. C.Thefailureofhercareeraftergraduation. D.Thehealthstateofpeopleinherhometown. 2Whydoestheauthortakethefootballteamasanexample? A.Toadvocatetheconceptofindependence. B.Tostresstheimportanceofteamwork. C.Tosupporttheideaofco﹣opmodel. D.Toexplorethekeytosuccess. 3WhatisAyers﹣Elliott'sattitudetowardsthefutureofFootPrintFarms? A.Optimistic. B.Skeptical. C.Cautious. D.Ambiguous. 4Whatisthemainideaofthetext? A.Naturallygrownfoodbenefitspeople'shealth. B.FoodPrintFarmsismakingadifferenceinMississippi. C.Ayers﹣Elliottencouragespeopletoexperiencefarm D.AgritourismisbecomingincreasinglypopularinAmerica.
8分AngelGarciaCrespoisacomputerengineeratCarlosIIIUniversityofMadridinSpain.Hisgrouphasinventedanewwayfordeaf﹣blindpeopletowatchTV.Theideaforthetechnologygrewoutofpreviousworkbyhisgroup.Theteamhadalreadyworkedonmakingaudiovisual视听的materialsaccessibletopeoplewitheithervisionorhearingdisabilities.Butthegroupwantedtohelppeoplewithbothchallenges.Sotheyaskedsomedeaf﹣blindpeoplewhatwouldhelp. Inadditiontorelyingontheirsenseoftouchtocommunicate?deaf﹣blindpeoplecanalsogetandsendinformationwithaBrailleline.TheBraillesystemusespatternsofraiseddotstostandforlettersandnumbers.ABraillelineisanelectronicmachinewithachangeableBrailledisplay.Dotsriseupordropdownbasedontheinformationsenttothemachine. NowthenewsystemchangesTVsignalstodataaBraillelinecanuse.Thekeytothesystemisthepossibilityofusingsubtitles字幕tocollectTVinformationGarciaCrespoexplains.Subtitlestravelwiththeimage影像andtheaudioinelectromagneticwaveswedon'tsee.Butanelectronicsystemcankeepthosewaves. Firstacomputerprogramorapppullsoutthesubtitlesandvisualdescriptionsfromthebroadcastsignal.ThesystemthencombinestheinformationandchangesbothintodataforBraille. Nowanotherappgetstoworkwhichsendsthedataouttopeople'sBraillelinesondemand.ThisisdoneinrealtimeinlessthanasecondGarciaCresposays.Thisletsadeaf﹣blindpersonwatchTVasit'sbroadcast.ThesystemwillworkwithvariousBraillelinesaslongasthere'sabluetoothconnectionavailable.NowthesystemisonlyusedinEuropeanditshouldsoonbeavailableintheUS. 1WhatinspiredGarciaCrespo'sgrouptoworkonthenewtechnology? A.Deaf﹣blindpeople'spoorlife. B.Theirpityonthedisabledpeople. C.Thechallengestheyfaceinwork. D.Theirgroup'spreviousresearch. 2WhycantheelectronicsystemcollectTVinformation? A.Itcancombineallkindsofbroadcastsignals. B.Itcankeepthewaveswithsubtitlestraveling. C.ItcanworktogetherwithavarietyofBraillelines. D.Itcanpulloutthesubtitlesandvisualdescriptions. 3Whatdoestheauthorthinkofthefutureofthenewtechnology? A.Challenging. B.Bright. C.Rewarding. D.Hopeless. 4Whatshouldbeasuitabletitleforthetext? A.NewTechnologyIsImprovingDeaf﹣blindPeople'sLife B.ANewBrailleLineIsAppliedtoDisabledPeople'sLife C.ASpanishGroupMakesTVAccessibletoBlindPeople D.NewTechnologyHelpsDeaf﹣blindPeopleWatchTV
用NA表示阿伏加德罗常数的值下列说法正确的是
如图为模拟远距离输电的部分测试电路.ab端接电压稳定的正弦交变电源定值电阻阻值分别为R1R2且R1<R2理想变压器的原副线圈匝数比为k且k<1电流表电压表均为理想表其示数分别用I和U表示.当向下调节滑动变阻器R3的滑动端P时电流表电压表示数变化分别用△I和△U表示.则以下说法正确的是
某同学测定电源电动势和内阻所使用的器材有待测干电池一节内阻很小电流表A量程0.6A内阻RA小于1Ω电流表A1量程0.6A内阻未知电阻箱R10~99.99Ω滑动变阻器R20~10Ω单刀双掷开关S单刀单掷开关K各一个导线若干. 1该同学按图甲所示电路连接进行实验操作.请在答题卡相应位置的虚线框内补全与图甲对应的电路图. 2测电流表A的内阻闭合开关K将开关S与C接通通过调节电阻箱R1和滑动变阻器R2读取电流表A的示数为0.20A电流表A1的示数为0.60A电阻箱R1的示数为0.10Ω则电流表A的内阻RA=Ω. 3测电源的电动势和内阻断开开关K调节电阻箱R1将开关S接填“C”或“D”记录电阻箱R1的阻值和电流表A的示数断开开关K开关S所接位置不变多次调节电阻箱R1重新实验并记录多组电阻箱R1的阻值R和电流表A的示数I. 4数据处理图乙是由实验数据绘出的﹣R图象由此求出干电池的电动势E=V内阻r=Ω.计算结果保留二位有效数字 5如果电流表A的电阻未知本实验填“能”或“不能”测出该电源的电动势.
假定你是李华你的家乡将举行庆祝首个中国农民丰收节ChineseFarmers'HarvestFestival活动请你写封邮件邀请你的新西兰朋友Eric来参加内容包括 1.时间和地点 2.活动内容民俗文化表演美食品尝及观光活动等. 注意 1.词数100左右 2.可以适当增加细节以使行文连贯.
如图所示一足够长的木板在光滑水平面上以速度v向右匀速运动现将质量为m的物体竖直向下轻轻地放置在木板上的右端已知物体和木板之间的动摩擦因数为μ.为保持木板的速度不变须对木板施一水平向右的作用力F.从物体放到木板上到它相对木板静止的过程中木块与物体组成的系统产生的内能为
如图所示间距为L的水平平行金属导轨上连有一定值电阻阻值为R两质量均为m的导体棒ab和cd垂直放置在导轨上两导体棒电阻均为R棒与导轨间动摩擦因数均为μ导轨电阻不计最大静摩擦力等于滑动摩擦力整个导轨处在竖直向下的匀强磁场中磁感应强度为B.现用某一水平恒力向右拉导体棒ab使其从静止开始运动当棒ab匀速运动时棒cd恰要开始滑动从开始运动到匀速的过程中流过棒ab的电荷量为q重力加速度为g求 1棒ab匀速运动的速度大小 2棒ab从开始运动到匀速运动所经历的时间是多少 3棒ab从开始运动到匀速的过程中棒ab产生的焦耳热是多少
10分Choosingamajorisaveryimportantthinginourlife.Howeveratthesametimeitcanbeextremelychallenging.Soit'snecessarytolearnsomesimpletipsthatwillmakeyourdecisionmucheasier.1.Andhowdoesthatchoiceaffectyourfuturecareer?Wecanhelpguideyouinchoosingamajor. Yourmajorisyourprimaryfieldofstudyinyourundergraduate大学的program.Itisthesubjectinwhichyoueamyourbachelor'sdegree.Aftercompletingalistofgeneraleducationcoursesyouspendtherestofthetimestudyingonesubjectofyourchoice.2. Formanystudentsit'sbesttotryoutdifferentclassestofigureoutamajoryou'IIlikebutyouneedtohaveacoupleofsolidchoices.3youshouldbegintakingcoursesyouarerequired tocompletebeforegraduationsoitwilldecreaseyourchancesofneedingtoswitchmajorslaterbecauseyouakeadyknowwhattoexpect. 4youshouldbeginthinkingabouthowyourfieldwillleadtoajobassoonaspossible. Considerclubsresearchprogramsandpart﹣timejobsrelatedtopotentialcareerchoicesforyourmajor. Formorecareer﹣specificmajorslikenursingandengineeringthemajorityofyourstudieswillincludeskillsthatcanbeusedinafuturejob.5.Thesooneryoubeginworkinginalabonresearchprojectsorhelpingasateachingassistantforaprofessorthebetteryou'IIbeabletofigureoutyourcareer. A.Youhavetothinkofwaystochooseamajor B.Besurethatyouchooseamajorthatsuitsyourinterests C.Onceyouhaveabetterideaofwhichmajoryoulikebest D.Whileyourmajormayormaynotleaddirectlytoacareer E.Dosomeresearchtofindoutwhichmajorscanhelpyougetthatjob F.Roughlyone﹣thirdtoone﹣halfofyourcourseswillberelatedtoyourmajor G.Howeveryoushouldstillconsiderdoingactivitiesoutsideoftheclassroomtobetterprepareyou
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