PC2023-P5 Best solutions and final results

Problem 5 – Light sources

In total, 35 solutions were submitted for problem 5, out of which 32 were correct.
Congratulations to everyone who managed to solve this problem!

The Best Solution Awards were selected from the 19 submissions sent before the first hint was published. Since the problem was fairly straightforward, not much variety in approaches was possible. Indeed, all the solutions were following the same approach. Therefore, the best solutions were chosen based on additional insight given in the solutions. There were three solutions providing insight exceeding what was strictly needed for the solution, those of Lukas Schicht, Marinus Lehmann and Lincoln Liu. Marinus discussed if the assumption of neglecting the intensity dependence on distance from the source was reasonable while Lukas and Lincoln discussed the question if it is possible to have such local intensity maxima which are not global maxima, i.e. the waves from the three sources are not in the same phase. Although Lincoln has some typos in his analysis of the local maxima, the general framework of his approach remains valid. Since Lukas has a very nice proof, he will get 0.4 of the bonus while Marinus and Lincoln share the remaining 0.6 between them equally. Additionally, there were three very well written solutions with step-by-step instructions how to construct the positions of the sources, provided by Anindya Guria and Eppu Leinonen (each of them receives the 0.1-bonus).

Final results for Problem 5

Pre-university students:

First nameSurnameCountrySchool/UniversityP5 date time
DD/MM/YY 00:00:00
P5 Score
LincolnLiuHong KongSha Tin College26/3/23 15:142.8935
GuotaoHeChinaNanning No.3 High School26/3/23 14:012.5937
TomasBabelisLithuaniaVilniaus jėzuitų gimnazija26/3/23 15:092.3579
RhythmKediaIndiaMB International26/3/23 17:381.9487
Ilan, Ivan (Team)Mihelja, HegedićCroatiaXV. gymnasium Zagreb, V. gymnasium Zagreb27/3/23 00:091.7716
EppuLeinonenFinlandMunkkiniemen yhteiskoulu27/3/23 15:151.6181
Chung WangLamHong KongSt. Paul’s Co-educational College27/3/23 14:271.6105
Ching YeungKwokHong KongShing Kung Hui Tang Shiu Kin Secondary School3/4/23 13:401.331
DženanMidžićBosnia and HerzegovinaJU Gimnazija “Bihać”3/4/23 16:481.21
YuchiZhangChinaUnited World College Changshu China6/4/23 12:550.99
AlexandarRoussevBulgaria12/4/23 16:580.9
GuangyuanChenSingaporeRaffles Institution17/4/23 16:100.8
ZilangShuChinaBeijing National Day School23/4/23 13:150.72
MichałKołodziejczykPolandI High School in Zielona góra25/4/23 19:430.7
Elias KoschierMichail OgnyanovAustriaERG Donaustadt7/5/23 12:210.6
MateuszKamińskiPolandVI High School in Cracow19/5/23 07:480.5
Yu ChengLimMalaysiaTaylor’s College13/5/23 13:360.5
Harold ScottChuaPhilippinesPhilippine Science High School – Main Campus18/5/23 14:430.5
FilipBaciakPoland1 LO w Chrzanowie14/5/23 08:060.5
RuichengMaChinaHarbin Normal University High School9/5/23 17:290.5

University students:

MarinusLehmannGermanyUniversity of Potsdam26/3/23 16:113.1829
LukasSchichtGermanyUniversity of Rostock26/3/23 18:242.9071
ZiyueWangChinaHebei University of Technology26/3/23 13:552.5937
AnindyaGuriaIndiaIndian Institute of Science26/3/23 17:042.369
LukaPassek-KumeričkiCroatiaUniversity of Zagreb27/3/23 16:271.7716
GilRonenIsraelHebrew University of Jerusalem28/3/23 14:401.6105
Bayram AlpŞahinTurkeyBogazici University29/3/23 11:101.4641
AlessioBiccariItalyLa Sapienza2/4/23 18:361.331
BowenTanChinaJilin Normal University4/4/23 06:491.21
KerimCherkezovTurkmenistanTurkmen State University16/4/23 20:110.88
KonstantinTripunovskiNorth MacedoniaUniversity of Ljubljana – Medical Faculty27/4/23 10:590.665
SoumyadeepSarmaIndiaIndian Institute of Science14/5/23 17:520.5

The list of countries:
Algeria, Argentina, Armenia, Australia, Austria, Azerbaijan, Bahrain, Bangladesh, Belarus, Belgium, Bosnia and Herzegovina, Brazil, Bulgaria, Cambodia, Cameroon, Canada, China, Croatia, Cuba, Czech Republic, Ecuador, Egypt, El Salvador, Estonia, Finland, France, Georgia, Germany, Greece, Guatemala, Honduras, Hong Kong, Hungary, India, Indonesia, Iran, Israel, Italy, Japan, Kazakhstan, Kenya, Kosovo, Kyrgyzstan, Latvia, Lithuania, Macau, Malaysia, Mexico, Moldova, Montenegro, Nepal, Netherlands, Nigeria, North Korea, North Macedonia, Pakistan, Peru, Philippines, Poland, Romania, Russia, Rwanda, Saudi Arabia, Serbia, Singapore, Slovakia, Slovenia, South Africa, South Korea, Spain, Sri Lanka, Suriname, Sweden, Switzerland, Syria, Taiwan, Tajikistan, Thailand, Turkey, Turkmenistan, Ukraine, United Arab Emirates, United Kingdom, United States, Uzbekistan, Vietnam.