国际物理林匹克竞赛试题Int Physics Olympiad Questions 1_2_3

《国际物理林匹克竞赛试题Int Physics Olympiad Questions 1_2_3》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、6Q1θθdFigure1.1Aplanemonochromaticlightwave,wavelengthλandfrequencyf,isincidentnormallyontwoidenticalnarrowslits,separatedbyadistanced,asindicatedinFigure1.1.Thelightwaveemergingateachslitisgiven,atadistancexinadirectionθattimet,bywheretheamplitudeaisthesameforbothwaves.(Assumexismuchlar

2、gerthand).(i)Showthatthetwowavesobservedatanangleθtoanormaltotheslits,havearesultantamplitudeAwhichcanbeobtainedbyaddingtwovectors,eachhavingmagnitude,andeachwithanassociateddirectiondeterminedbythephaseofthelightwave.Verifygeometrically,fromthevectordiagram,thatwhere(ii)Thedoubleslitisr

3、eplacedbyadiffractiongratingwithNequallyspacedslits,adjacentslitsbeingseparatedbyadistanced.Usethevectormethodofaddingamplitudestoshowthatthevectoramplitudes,eachofmagnitudea,formapartofaregularpolygonwithverticesonacircleofradiusRgivenbyDeducethattheresultantamplitudeis6andobtaintheresu

4、ltantphasedifferencerelativetothatofthelightfromtheslitattheedgeofthegrating.(iii)Sketch,inthesamegraph,sinNβand(1/sinβ)asafunctionofβ.Onaseparategraphshowhowtheintensityoftheresultantwavevariesasafunctionofβ.(iv)Determinetheintensitiesoftheprincipalintensitymaxima.(v)Showthatthenumberof

5、principalmaximacannotexceed(vi)Showthattwowavelengths,whereδλ<<λ,produceprincipalmaximawithanangularseparationgivenbyCalculatethisangularseparationforthesodiumDlinesforwhich6OQ2InternationalPhysicsOlympiad19562.Earlythiscenturyamodeloftheearthwasproposedinwhichitwasassumedtobeasphereofra

6、diusRconsistingofahomogeneousisotropicsolidmantledowntoradiusRc.ThecoreregionwithinradiusRccontainedaliquid.Figure2.1XERRC2θRFigure2.1ThevelocitiesoflongitudinalandtransverseseismicwavesPandSwavesrespectively,areconstant,VP,andVSwithinthemantle.Inthecore,longitudinalwaveshaveaconstantvel

7、ocityVCP,