复旦大学《大学物理》课件（英文）-第2、3章(1).pdfVIP免费

Chapter2MotioninonedimensionKinematicsDynamicsAtanyparticulartimet,theparticlecanbelocatedbyitsx,yandzcoordinates,whicharethethreecomponentsofthepositionvector:where,andarethecartesianunitvectors.Section2-3Position,velocityandaccelerationvectors1.Positionvectorkjir→++=kzjyixrxyzFig2-11ijkrOWedefinedthedisplacementvectorasthechangeinpositionvectorfromt1tot2.2.Displacement(位移)12rrr−=rNote:1)Displacementisnotthesameasthedistancetraveledbytheparticle.2)Thedisplacementisdeterminedonlybythestartingandendingpointsoftheinterval.yz1r1t2tt=t=Fig2-12x2rsOr222:Magnitudezyxr++=Direction:fromstartpointtoendpoint...