天文学英文版PPT资料 (6)

UniverseEighthEditionRogerA.Freedman•WilliamJ.KaufmannIIICHAPTER4GravitationandtheWaltzofthePlanetsReadingAssignment–Chapter5(TheNatureofLight)Homework–Chapter3QuizdueWednesday9/15by9PMEpicyclesareusedinageocentricmodeltoexplaintheA.eastwardmotionofMars.B.westwardmotionofMars.C.phasesofVenus.D.appearanceofVenusintheearlymorningorlateeveningsky.E.phasesofthemoon.Q4.3EpicyclesareusedinageocentricmodeltoexplaintheA.eastwardmotionofMars.B.westwardmotionofMars.C.phasesofVenus.D.appearanceofVenusintheearlymorningorlateeveningsky.E.phasesofthemoon.A4.3WhenJupiterisatopposition(seediagram),itisoverhead(i.e.,onthemeridian)atA.6:00A.M.B.12:00noon.C.6:00P.M.D.midnight.E.neveratnight.Q4.1WhenJupiterisatopposition(seediagram),itisoverhead(i.e.,onthemeridian)atA.6:00A.M.B.12:00noon.C.6:00P.M.D.midnight.E.neveratnight.A4.1AplanetinanellipticalorbitaroundtheSunmovesmostrapidlywhenitisA.ataphelion.B.atperihelion.C.halfwaybetweenperihelionandaphelion.D.closertoaphelionthanperihelion.E.Noneoftheabove;ithasaconstantspeed.Q4.6AplanetinanellipticalorbitaroundtheSunmovesmostrapidlywhenitisA.ataphelion.B.atperihelion.C.halfwaybetweenperihelionandaphelion.D.closertoaphelionthanperihelion.E.Noneoftheabove;ithasaconstantspeed.A4.6Kepler’sthreelawsA.wereinitiallyderivedfromfundamentalphysicslaws.B.wereinitiallyfoundfromobservationandareempiricalrulesthatdescribehowtheplanetsmove.C.werehandeddownfromtheancientGreeks.D.werediscoveredbyKeplerinancientBabyloniantexts.E.arenowknowntobegrosslyincorrect.Q4.5Kepler’sthreelawsA.wereinitiallyderivedfromfundamentalphysicslaws.B.wereinitiallyfoundfromobservationandareempiricalrulesthatdescribehowtheplanetsmove.C.werehandeddownfromtheancientGreeks.D.werediscoveredbyKeplerinancientBabyloniantexts.E.arenowknowntobegrosslyincorrect.A4.5Twoplanetsareincircularorbitsaroundsimilarstars.Eachisthesamedistancefromitsparentstar.OneplanetisJupiter’ssize,whereastheotherisEarth’ssize.Whichofthefollowingistrue?A.TheJupiter-sizeplanethasamuchlongerperiodthantheEarth-sizeplanet.B.TheEarth-sizeplanethasamuchlongerperiodthantheJupiter-sizeplanet.C.Bothplanetshavethesameperiod.D.TheEarth-sizeplanethasaperiodexactlytwicethatoftheJupiter-sizeplanet.E.Notenoughinformationisgiventodeterminethecorrectanswer.Q4.7Twoplanetsareincircularorbitsaroundsimilarstars.Eachisthesamedistancefromitsparentstar.OneplanetisJupiter’ssize,whereastheotherisEarth’ssize.Whichofthefollowingistrue?A.TheJupiter-sizeplanethasamuchlongerperiodthantheEarth-sizeplanet.B.TheEarth-sizeplanethasamuchlongerperiodthantheJupiter-sizeplanet.C.Bothplanetshavethesameperiod.D.TheEarth-sizeplanethasaperiodexactlytwicethatoftheJupiter-sizeplanet.E.Notenoughinformationisgiventodeterminethecorrectanswer.A4.7Whichofthefollowingobjectshaszeroacceleration?A.AcarjuststartingoutfromastoplightB.Acartravelingat70milesperhouronalongstraightinterstatehighwayC.Acarexitinganinterstateonacurvedoff-rampD.AcarslowingdownforaredlightE.AcarskiddingtoastoptoavoidanaccidentQ4.9Whichofthefollowingobjectshaszeroacceleration?A.AcarjuststartingoutfromastoplightB.Acartravelingat70milesperhouronalongstraightinterstatehighwayC.Acarexitinganinterstateonacurvedoff-rampD.AcarslowingdownforaredlightE.AcarskiddingtoastoptoavoidanaccidentQ4.9ThetidalforceoftheMoonontheEarthoccursbecauseA.theMoonpullsmorestronglyonthenearsideoftheEarththanthefarsideoftheEarth.B.theMoonpullsmorestronglyonthefarsideoftheEarththanthenearsideoftheEarth.C.theMoonpullsequallystronglyonthenearsideandthefarsideoftheEarth.D.theMoonkeepsitssamefacetowardtheEarth.E.theMoonisinasynchronousorbit.Q4.14ThetidalforceoftheMoonontheEarthoccursbecauseA.theMoonpullsmorestronglyonthenearsideoftheEarththanthefarsideoftheEarth.B.theMoonpullsmorestronglyonthefarsideoftheEarththanthenearsideoftheEarth.C.theMoonpullsequallystronglyonthenearsideandthefarsideoftheEarth.D.theMoonkeepsitssamefacetowardtheEarth.E.theMoonisinasynchronousorbit.A4.14KeyIdeasCopernicus’sHeliocentricModel:Copernicus’sheliocentric(Sun-centered)theorysimplifiedthegeneralexplanationofplanetarymotions.Inaheliocentricsystem,theEarthisoneoftheplanetsorbitingtheSun.AplanetundergoesretrogrademotionasseenfromEarthwhentheEarthandtheplanetpasseachother.Thesiderealperiodofaplanet,itstrueorbitalperiod,ismeasuredwithrespecttothestars.ItssynodicperiodismeasuredwithrespecttotheEarthandtheSun(forexample,fromoneoppositiontothenext).KeyIdeasApparentMotionsofthePlanets:LiketheSunandMoon,theplanetsmoveonthecelestialspherewithrespecttothebackgroundofstars.Mostofthetimeaplanetmoveseastwardindirectmotion,inthesamedirectionastheSunandtheMoon,butfromtimetotimeitmoveswestwardinretrogrademotion.TheAncientGeocentricModel:AncientastronomersbelievedtheEarthtobeatthecenteroftheuniverse.Theyinventedacomplexsystemofepicyclesanddeferentstoexplainthedirectandretrogrademotionsoftheplanetsonthecelestialsphere.KeyIdeasKepler’sImprovedHeliocentricModelandEllipticalOrbits:Copernicusthoughtthattheorbitsoftheplanetswerecombinationsofcircles.UsingdatacollectedbyTychoBrahe,Keplerdeducedthreelawsofpl