工程力学双语课件ch01-BasicConcepts

StaticsandStrengthofMaterials,WangMing-lu,Chapter1:BasicConcepts,ChapterObjectives,1.PerformnumericalcomputationsandconversionsusingU.S.customaryunitsandtheSI.2.Usestandardtrigonometricformulasintheanalysisofrightandobliquetriangles.3.Solvegroupsoftwoandthreesimultaneouslinearequations.,SpecializedVocabulary,Statics:静力学,静止状态,静态Mechanics:力学,机械学Strength：强度Equilibrium:平衡Unit:个体,(计量)单位,数学最小的整数Customaryunit:惯用单位，常用单位SI：InternationalSystemofUnits国际单位制Weight：重量Mass：质量,WhatisMechanics?,1.1Introduction,Mechanicsisfullyconnectedwithourdailylife,Crane,Howmuchbalanceweightshallbeplacedhere?,Statics(静力学)Equilibrium(平衡),1.1Introduction,Crane,Strength(强度),Internalforcesoftruss(桁架内力),1.1Introduction,Aphotoofrollingwheel,Distinct,Indistinct,Kinematics(运动学)Planarmotionofrigidbody,1.1Introduction,Mechanicsandbridge.,OnJan.4，1999，TherainbowbridgewhichwaslocatedinSichuanprovince,collapsedwhileagroupofsoldierpassedoverit.40peoplediedincludingthesesoldiers.,1.1Introduction,Mechanicsandwirewalking,StableEquilibrium(稳定平衡)Masscenter(质心),1.1Introduction,Mechanicsandairplane.,1.1Introduction,Mechanicsandhydroproject,ThreeGeorgesProject,1.1Introduction,MechanicsandMachineDesign,Dosetheshoesmellok?,1.1Introduction,1.1Introduction,1.AboutStatic.Staticisthebranchofmechanicswhichstudiesthelawsofequilibriumofbodiesundertheactionofforcesystems.Itmainlystudiessimplificationsandequilibriumconditionsofforcesystemsandapplicationsofthecorrespondingresults.2.AboutStrength/Mechanicsofmaterials.3.Aboutthestudyofthiscourse.,1.1Introduction,1.Aboutstatic.2.AboutStrength/Mechanicsofmaterials.Undertherequestthatthestrength,rigidity,stabilityaresatisfied,offerthenecessarytheoreticalfoundationandcalculationmethodfordeterminingreasonableshapesanddimensions,choosingpropermaterialsforthecomponentsatthemosteconomicprice.3.Aboutthestudyofthiscourse.,1.2-1.4UnitsantConversionofit,Length1in.=25.40mm1in.=0.02540m1ft.=0.3048mForce1lb=4.448N1kip=4.448kN,1mm=0.03937in.1m=39.37in.1m=3.281ft1N=0.2248lb1kN=0.2248kip,1.5-1.8TrigonometricFormulasandLinearEquatio