欢迎来到天天文库
浏览记录
ID:14552239
大小:418.50 KB
页数:10页
时间:2018-07-29
《gre物理sub题目精选解答》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、电磁学1.AFastchargedparticlepassesperpendicularlythroughathinglasssheetofindexofrefraction1.5.TheconeofCerenkovlight,emittedintheglassatangleθ,isincidentontheglass-airinterfaceatthecriticalanglefortotalreflection.Whatisthespeedoftheparticle?answer:2.answer:D3.answer:E一些简单
2、的量子力学题:1.Aparticleofchargeeandmassmistrappedinaone-dimentionalsquarewellofwidth2awithimpenetrablewalls.Thewallsarelocatedatx=−aandx=a.(1)Ifthequantummechanicalstatesarelabledbyn(n=1isthegroundstate),whatistheexpectationvalueofx^2forverylargen?answer:a^2/3(2)Asmallelect
3、ricfieldofstrengthE_0isappliedinthexdirection.Whatisthechangeoftheenergyofthefirstexcitedstateofthisparticleduetothiselectricfield?(Assumethatthetotalpotential,duetothewallsandtheelectricfield,is0atx=0.)answer:02.ThewavefunctionwhereAandbarerealconstants,isanormalizede
4、igenfunctionoftheSchrödingerequationforaparticleofmassMandenergyEinaonedimensionalpotentialV(x)suchthatV(x)=0atx=0.DeterminetheformofthepotentialV(x)answer:3.answer:E统计:1.answer:B2.answer:BA一些简单的粒子物理题和狭义相对论1.Thehalf-lifeofamesonatrestis2.5×10-8second.Abeamofmesonsisgen
5、eratedatapoint15metersfromadetector.Onlyhalfofthemesonslivetoreachthedetector.Findthespeedofthemesonanswer:2.3.Abeamofparticlesisincidentonathintargetofthicknesst.Ifthecrosssectionpernucleusforascatteringoftheparticlesbythenucleioftheofthetargetisσ,andthenumberofnuclei
6、perunitvolumeisn,whatisthefractionofparticlesscattered?answer:ntσ4.Aprotonbeamisincidentonascatterer0.1centimeterthick.Thescatterercontains10^20targetnucleipercubiccentimeter.Inpassingthroughthescatterer,oneprotonperincidentmillionisscattered.Calculatethescatteringcros
7、ssection.answer:10^-25cm^2
此文档下载收益归作者所有