GunterMarxPhotography/CORBISMotion,Forces,andEnergyThiskayakerbattlestherapidsontheThompsonRiverinBritishColumbia,Canada.AkayakertakesadvantageofNewton’sthirdlaw.Thepaddleexertsaforceonthewaterandthewaterexertsanequal,butopposite,forceonthekayaker.Sendallinquiriesto:Glencoe/McGraw-Hill8787OrionPlaceColumbus,OH43240-4027ISBN:0-07-861770-7PrintedintheUnitedStatesofAmerica.2345678910027/111090807060504Copyright©2005byTheMcGraw-HillCompanies,Inc.Allrightsreserved.ExceptaspermittedundertheUnitedStatesCopyrightAct,nopartofthispublicationmaybereproducedordistributedinanyformorbyanymeans,orstoredinadatabaseorretrievalsystem,withoutpriorwrittenpermissionofthepublisher.TheNationalGeographicfeaturesweredesignedanddevelopedbytheNationalGeographicSociety’sEducationDivision.Copyright©NationalGeographicSociety.Thename“NationalGeographicSociety”andtheYellowBorderRectanglearetrademarksoftheSociety,andtheiruse,withoutpriorwrittenpermission,isstrictlyprohibited.The“ScienceandSociety”andthe“ScienceandHistory”featuresthatappearinthisbookweredesignedanddevelopedbyTIMESchoolPublishing,adivisionofTIMEMagazine.TIMEandtheredborderaretrademarksofTimeInc.Allrightsreserved.GunterMarxPhotography/CORBISCONTENTJackCooperEnnisHighSchoolEnnis,TXSandraK.Enger,PhDAssociateDirector,AssociateProfessorUAHInstituteforScienceEducationHuntsville,ALCarlZorn,PhDStaffScientistJeffersonLaboratoryNewportNews,VAMATHMichaelHopper,DEngManagerofAircraftCertificationL-3CommunicationsGreenville,TXTeriWillard,EdDMathematicsCurriculumWriterBelgrade,MTREADINGBarryBartoSpecialEducationTeacherJohnF.KennedyElementaryManistee,MISAFETYAileenDuc,PhDScience8TeacherHendrickMiddleSchool,PlanoISDPlano,TXSandraWest,PhDDepartmentofBiologyTexasStateUniversity-SanMarcosSanMarcos,TXACTIVITYTESTERSNermaCoatsHendersonPickeringtonLakeviewJr.HighSchoolPickerington,OHMaryHelenMariscal-CholkaWilliamD.SliderMiddleSchoolElPaso,TXScienceKitandBorealLaboratoriesTonawanda,NYM◆iiiAuthorsSeriesConsultantsSharlaAdamsIPCTeacherAllenHigh...
