200 More Puzzling Physics Problems - With Hints and Solutions

498 Pages·011.607 MB·English

by  Gnadig P., Honyek G., Riley K.F.

200MorePuzzlingPhysicsProblems
WithHintsandSolutions
Likeitspredecessor,200PuzzlingPhysicsProblems,thisbookisaimedatstrengthening
students’ grasp of the laws of physics by applying them to situations that are practical
and to problems that yield more easily to intuitive insight than to brute-force methods
andcomplexmathematics.Theproblemsarechosenalmostexclusivelyfromclassical(i.e.
non-quantum)physics,butarenoeasierforthat.Theyareintriguinglyposedinaccessible
non-technical language, and require readers to select an appropriate analysis framework
and decide which branches of physics are involved. The general level of sophistication
neededisthatoftheexceptionalschoolstudent,thegoodundergraduateorthecompetent
graduatestudent.Somephysicsprofessorsmayfindsomeofthemoredifficultquestions
challenging.Bycontrast,themathematicaldemandsarerelativelyminimal,andseldomgo
beyondelementarycalculus.Thisfurtherbookofphysicsproblemsshouldprovenotonly
instructiveandchallenging,butalsoenjoyable.
péter gnädig graduated as a physicist from Eötvös University (ELTE) in Budapest in 1971 and
receivedhisPhDdegreeintheoreticalparticlephysicstherein1980.Heworkedasaresearcher(in
high-energyphysics)andalecturerintheDepartmentofAtomicPhysicsatELTEuntilheretired
in 2010. Between 1985 and 2004 he was one of the leaders of the Hungarian Olympic team that
tookpartintheInternationalPhysicsOlympiad.Since1989hehasbeenthephysicseditorforthe
MathematicalandPhysicalJournalforSecondarySchools(Budapest).Heisoneoftheauthorsof
200PuzzlingPhysicsProblems.
gyulahonyekgraduatedasaphysicistfromEötvösUniversity(ELTE)in1975andfinishedhis
PhDstudiestherein1977,afterwhichhestayedonasaresearcherandlecturerintheDepartment
ofGeneralPhysics.In1984,followingatwo-yearpostgraduatecourse,hewasawardedateacher’s
degreeinphysics.In1985hetransferredtotheteachertrainingschoolatELTE,andheldapostas
mentorandteacheratRadnótiGrammarSchool(Budapest)untilhisretirementin2011.Between
1986 and 2011 he was one of the leaders of the Hungarian Olympic team that took part in the
InternationalPhysicsOlympiad.Heisalsooneoftheauthorsof200PuzzlingPhysicsProblems.
máté vigh graduated as a physicist from Eötvös University (ELTE) in 2010, and will shortly be
proceedingtohisPhD.HetookpartintheInternationalPhysicsOlympiad(IPhO)in2003and2004
asacontestant,beingawarded,respectively,bronzeandsilvermedals.Since2012hehasbeenone
oftheleadersandtrainersoftheHungarianteamspreparingforandparticipatingintheIPhO.
ken riley read mathematics at the University of Cambridge and proceeded to a PhD there in
theoretical and experimental nuclear physics. As well as following a research career in particle
physics, he was the Senior Tutor at Clare College, Cambridge, and a University Lecturer at the
CavendishLaboratory,wherehetaughtphysicsandmathematicsforover40years.Amonghisother
publications are the widely established mathematics textbook Mathematical Methods for Physics
and Engineering (now in its third edition), and the physics problems books Problems for Physics
Studentsand200PuzzlingPhysicsProblems,allpublishedbyCambridgeUniversityPress.

200 More Puzzling Physics Problems
With Hints and Solutions
PéterGnädig
EötvösLorándUniversity,Budapest
GyulaHonyek
RadnótiGrammarSchool,Budapest
MátéVigh
EötvösLorándUniversity,Budapest
KenRiley
ConsultantEditorfortranslationandscientificediting
ClareCollege,Cambridge
UniversityPrintingHouse,CambridgeCB28BS,UnitedKingdom
CambridgeUniversityPressispartoftheUniversityofCambridge.
ItfurtherstheUniversity’smissionbydisseminatingknowledgeinthepursuitof
education,learningandresearchatthehighestinternationallevelsofexcellence.
www.cambridge.org
Informationonthistitle:www.cambridge.org/9781107103856
©P.Gnädig,G.HonyekandM.Vigh2016
Thispublicationisincopyright.Subjecttostatutoryexception
andtotheprovisionsofrelevantcollectivelicensingagreements,
noreproductionofanypartmaytakeplacewithoutthewritten
permissionofCambridgeUniversityPress.
Firstpublished2016
PrintedintheUnitedKingdombyTJInternationalLtd.PadstowCornwall
AcatalogrecordforthispublicationisavailablefromtheBritishLibrary
LibraryofCongressCataloguinginPublicationData
Names:Gnädig,Péter,author.
Title:200morepuzzlingphysicsproblemswithhintsandsolutions/Péter
Gnädig,EötvösLorándUniversity.
Othertitles:Twohundredmorepuzzlingproblemsinphysicswithhints
andsolutions
Description:Cambridge,UnitedKingdom;NewYork,NY:CambridgeUniversity
Press,2016.|©2016|Includesbibliographicalreferencesandindex.
Identifiers:LCCN2015037120|ISBN9781107103856(Hardback:alk.paper)|
ISBN1107103851(Hardback:alk.paper)|ISBN9781107503823(pbk.:alk.paper)|
ISBN1107503825(pbk.:alk.paper)
Subjects:LCSH:Physics–Problems,exercises,etc.
Classification:LCCQC32.G5232016|DDC530.076–dc23LCrecordavailable
athttp://lccn.loc.gov/2015037120
ISBN978-1-107-10385-6Hardback
ISBN978-1-107-50382-3Paperback
CambridgeUniversityPresshasnoresponsibilityforthepersistenceoraccuracy
ofURLsforexternalorthird-partyinternetwebsitesreferredtointhispublication,
anddoesnotguaranteethatanycontentonsuchwebsitesis,orwillremain,
accurateorappropriate.
Dedicatedto
FrederickKárolyházy
fromwhomwehavelearnedsomuch

Contents
Preface pageix
Howtousethisbook xiii
Thematicorderofproblems xv
Problems 1
Hints 65
Solutions 91
Appendix:Usefulmathematicalformulae 467
Physicsreferencetables 477
vii