France hosts 55th International Physics Olympiad

At the École Polytechnique south of Paris in July, more than 400 high school students from more than 80 countries could be seen dropping and rolling steel balls into beds of sand. The challenges—to find relationships between crater diameter and ball energy and to determine whether the ball experiences solid friction or fluid drag in the sand—were among several that the students tackled in the 55th International Physics Olympiad (IPhO).

IPhO is an annual competition for high school students that tests knowledge and skills in theoretical and experimental physics. Held 18–24 July, this year’s competition had more than double the number of contestants as the 2024 edition, which was hosted in Isfahan, Iran. The US physics team and several European teams opted to compete in the European Physics Olympiad last year instead of in IPhO because of state advisories discouraging travel to Iran.

In the latest competition, 37 gold medals were awarded to students from 15 countries. The top overall scorer was South Korea’s Hyeokjoon Lee, who earned 43.2 of 50 possible points. The highest scorer for the experimental exam was Romania’s Ionut-Gabriel Stan, who came in eighth overall. China’s Tong Pengyu, who placed second overall, earned the highest score in the theoretical exam. The US team finished first in combined points and was the only country to take home five gold medals. The last time all US participants received gold medals was in 2021.

The US team was composed of Agastya Goel (Palo Alto, California), Allen Li (Cupertino, California), Joshua Wang (Brookfield, Wisconsin), Feodor Yevtushenko (Irvine, California), and Brian Zhang (Northville, Michigan). The 5 students were selected from a group of 20 who had qualified for a weeklong physics boot camp at the University of Maryland in June. The camp was led by Tengiz Bibilashvili, a professor at the University of California, Santa Barbara. The team is sponsored by the American Institute of Physics (publisher of Physics Today), the American Association of Physics Teachers and AIP’s other member societies, and additional groups.

For the experimental exam, along with the ball-in-the-sand challenge, contenders measured the horizontal component of Earth’s magnetic field. They constructed Gouy balances, which measure the apparent change in mass of an object as it passes through a magnetic field. For the theoretical questions, students calculated the mass distribution of the Milky Way, modeled a clock powered by fluctuations in atmospheric pressure, and investigated the characteristic bubbles of champagne.

Bibilashvili notes that Zhang identified an error in the first question of the theoretical exam and so did not answer it. The organizers decided to award him full credit.

Despite their performance, the US students don’t cite gold medals as their motivation for competition. Goel, who placed 12th overall, says that the value of IPhO is in the preparation and the enjoyment he gets from learning along the way. Yevtushenko, in 29th place, says that the physics camp community is what makes the competition special.

When they were not busy with the theoretical and experimental physics exams, competitors visited cultural landmarks and participated in activities. For example, they toured museums, cruised the Seine, took in a mime performance, and danced to the Drumteam Paris percussion company. Despite their packed schedule, the students still had time to learn more physics. They gathered at the École Polytechnique to hear French physicists talk about nuclear energy, the James Webb Space Telescope, and glass manufacturing, among other topics.

Next year’s competition will be held in July in Bucaramanga, Colombia.