大学物理英文版PPT.pptVIP

UNIVERSITYPHYSICS1,大学物理（英文版）多媒体课件,Introduction,Chapter1Kinematics,Chapter2NewtonsLawsofMotion,Chapter3WorkandEnergy,Chapter4Momentum,Chapter5Rotationofarigidbody,Chapter6TheKineticTheoryofGases,Chapter7FundamentalsofThermodynamics,Volume1,Introduction,2001.9.11Catastrophe（大灾难）,宇宙：约1250亿个星系，每个星系由数千亿个恒星组成。,银河系太阳系：地球，星星看得见的：你我他它分子原子原子核基本粒子,相对论天体物理经典物理:力学，热等量子力学核物理量子场论,银河系,相对论天体物理,量子天体物理学,史蒂芬.霍金时间简史,TheGalaxySun:Earth,PlanetsThebodywecanseeMoleculesatomsnucleielementaryparticles,ThegeneralreletivityastrophsicsNewtonsMechanicsHeat,ThermodynamicsElectromagneticTheoryQuantumMechanicsNuclearPhysicsQuantumFieldTheory,Theory,Ourworldanduniverse,宇宙半径：1026m,地球1024kg,银河系：1044kg,我们的母亲：地球,1969年7月16日美国东部时间9时23分阿波罗11号发射升空。,三天后阿姆斯特朗奥尔德林柯林斯,Mars(火星）,机遇号,ThesurfaceofMars(火星表面）,OurworldandUniverse,Universe,Elementaryparticles,Theancientphysics,Theclassicalphysics,Themodernphysics,Intheviewofphysicshistory:,主要讲授内容：,经典力学相对论,热学,电磁学,波动光学,振动与波动,量子论简介,日常生活,Physics,Chemistry化学,Biology生物学,Computer计算机科学,Mechanics机械学,Medicine医学,Physics:fundamentalsandmethods.,References(参考书）,张达宋物理学基本教程李行一等，物理学基本教程教学参考书李行一等，物理学基本教程习题分析与解答张三慧等，大学物理学Hallidayet.alFundamentalsofPhysicsW.Searset.alUniversityPhysics史蒂芬.霍金，时间简史盛正卯等，物理学与人类文明B.K.里德雷，时间、空间和万物.,PartOneMechanics力学,Chapter1Kinematics（运动学）质点运动学,第一章质点运动学(Kinematics),1-1参考系质点Frameofreferenceparticle,1-2位置矢量位移Positionvectoranddisplacement,13速度加速度Velocityandacceleration,1-4两类运动学问题TwotypesofProblems,1-6运动描述的相对性Relativemotion,1-5圆周运动及其描述Circularmotion,1.理解描述质点运动物理量的定义及其矢量性、相对性和瞬时性；2.掌握运动方程的物理意义，会用微积分方法求解运动学两类问题；3.掌握平面抛体运动和圆周运动的规律；4.理解运动描述的相对性，会用速度合成定理和加速度合成定理解题。,教学基本要求,重要历史人物,伽利略GalileoGalilei:15641642意大利物理学家、数学家、天文学家，近代实验科学的创始人。,主要贡献：发明了望远镜，维护、坚持和发展了哥白尼学说，发现木星的四个卫星；摆的等时性、惯性定律、落体运动定律；运动的合成原理和独立性原理，相对性原理；方法：实验科学。,1-1FrameofReferenceParticle(质点）,1.FrameofReference（参照系）,Whenwediscussthepositionandthevelocity（速度）ofanobject,wemustanswerthequestions:“positionwithrespectto（相对于）what?”and“Velocitywithrespecttowhat?”,Ifwechoosedifferentobjectsasthereferenceframestodescribethemotionofagivenbody,theindications(结果）willbedifferent.,Itisconvenienttotaketheearthssurfaceasourframeofreferenceinmostcasesinthiscourse.(Whatcases?),Coordinatesystem（坐标系）:fixedontheframe,relativetowhichposition,velocity,accelerationandorbitoftheobjectcanbespecifiedquantitatively.CartesianCoordinatesystem(直角坐标系）：,Quantitatively:定量地,2.Particles（质点）,Particle(质点）isanidealmodel,insomecircumstances（情况、形势）.Wecantreatabodyasaparticle,andconcentrateonitstranslationalmotion(平动）andignore（忽略）alltheothermotions.,点：有质量无大小无体积,3.Time（时刻）andtimeinterval(时间）,Timetisagiveninstant,andtimeinterval(间隔）tisthedifferenceoftwogiveninstants.Weusetheformertodescribe（描述）thestateoftheobject,thelattertodescribetheprocess.（过程）,4.Units(单位）,InternationalSystemofUnits(SI:SystmeInternationaldUnits法语）isusedinChina,kg:千克kilogram,m:米meter,s:秒second,5.Scalarandvector（标量和矢量）:,Twotypesofphysicalquantities（量）:,Scalars:mass,length,speed,temperature.,Vectors:velocity,acceleration,momentum.,VectorA(black):itsmagnitude(大小）anddirection（方向）mayberepresentedbyalineOPdirectedfromtheinitialpointOtotheterminal（终）pointPanddenoted（标记）by,Addition（加）:ThetwovectorsAandBisaddedinfollowingway:C=A+BBA,C,A,B,InCartesiancoordinatesystem（直角坐标系）:,areunitvectorsalongOX,OY,OZ,Intwodimension（维）:,Obviously(显然）:,InonedimensionIntwodimensionInthreedimension,Inourteaching,wewillmainlydealwith（涉及）twodimensionalmotions:motioninaplane.,Mechanicalmotions,（机械运动）,1-2PositionVectorandDisplacement,1.PositionVector,PositionvectorisavectorthatextentsfromtheoriginofthecoordinatesystemtotheparticlespositionasshowninFigure,Magnitude:,Inthetwodimension:,Itstwocomponents（分量）,Pathequation(轨迹方程）,2.Displacement(位移):,Displacementisintroducedtodescribethechangeinpositionduringagiventimeinterval:,Thatis,Itsmagnitude（大小),Thegeometrical（几何）meaningofandthedifferencesamongthem.,Note:,Solution:,1-3Velocity（速度）andAcceleration（加速度）,Average（平均）velocity：,1.Velocity,whichhasadirectionassameasthatof,Averagespeed(速率）:,（Instantaneous瞬时）velocityattimet：,Itisinthetangent(切线）ofthepathandpointsattheadvancedirection.,Direction:,Magnitude(大小）：,V-speed(瞬时）速率,时弧长等于弦长,Inthecoordinatesystem:,Magnitudeofthevelocity:,Theangleformedbetweenand+xdirectionisdeterminedby,Example1-2:Arabbitrunsacrossaparkinglot(近路）onwhichasetofcoordinateaxeshas,strangelyenough,beendraw.Thecoordinatesoftherabbitspositionasfunctionoftimetaregivenby:,withtinsecondsandxandyinmeters.Finditsvelocityatt=0.50s.,Solution:,Therabbitsvelocityatt=0.50sisequalto(等于）,2.Acceleration(加速度),Averageacceleration:,Instantaneousacceleration,Inthecoordinatesystem:,Itsmagnitudeanddirection:,指向曲线凹的一方,Example1.3:TheofaParticleis,whereandareconstants.Findthevelocityandacceleration.,Note:微分，细心，再细心！Carefully!,Solution:,Example1.4已知质点运动方程为x=2t,y=192t2,式中x,y以米计，t以秒计，试求：（1）轨道方程；（2）t=1s时的速度和加速度。,（2）对运动方程求导，得到任意时刻的速度,对速度求导，得到任意时刻的加速度：,解：（1）运动方程联立，消去时间t得到轨道方程,（1）,(2),将时间t=1s代入速度和加速度分量式(1)、(2)中，求出时间t=1s对应的速度和加速度：,速度大小和与x轴夹角,加速度大小和方向：,与y轴正向相反,Example1-5离水平面高为h的岸边，有人用绳以恒定速率V0拉船靠岸。试求：船靠岸的速度，加速度随船至岸边距离变化的关系式？,对时间求导得到速度和加速度：,由题意知：,解：在如图所示的坐标系中，船的位矢为：,因为：,1-4TwoTypesProblemsinKinematics,（2）Givenacceleration(orvelocity)andinitialcondition,findthevelocityandpositionvectorbymeansofvectorintegrationmethod积分法.,Ingeneral,therearetwokindsofproblemstobesolved:,(1)Givenpositionvector,findthevelocityandacce-lerationbyusingderivationmethod微分法.Seetheexamplesabove.,解：整理和分离变量可得下面方程,做积分：,Example1.6:某物体的运动规律为,式中k为常数，t=0，初速度为,求.,得：,请同学们完成积分,Example1.7:Aparticlemovesinaplanewithanacce-leration,wheregisconstant.Whent=0,itsvelocityisatainitialpoint(0,0).Finditsvelocityattimetandpathequation.,Using,wehave,Using,andtheinitialcondition(0,0),wehave,Solution:Itsvelocityis,Thepositionvectoroftheparticleis,1-5CircularMotion,1.TheimportanceofCircularmotion,(1)ThemovementsofSun,Earth,Planets,Electron,.,arerelatedtocircularmotion;,(2)Therearepartsofinstrumentsassociatedwiththecircularmotion:clock,car,.,(3)Theknowledgeoncircularmotionisthebasetostudythegeneralcurvilinearmotion（曲线运动）.,Youcanaccept(采用）theabovemethodtostudyCircularMotion。,Aparticleisincircularmotionifittravelsaroundacircleoracirculararc（弧）.,Uniformcircularmotion(匀速）:aroundacircleandatconstantspeed.,2.tangential（切向）,Changesthedirectionofthevelocity.,(2)Uniformcircularmotion(匀速):,Inthiscase，themagnitudeofvelocityisaconstant，thatis,whichmeansthatvelocitychangesonlyindirection.isusuallycalledthecentripetalacceleration（向心）.,Therefore,wehave,3.Generalcurvilinearmotion:,(1-30),istheradiusofcurvature（曲率）atAandCisthecenterofcurvaturecircle