Ortvay Problems and Solutions

2026

Hungary

Problems24 problemsProblems

1Echoes in a hemispherical hall*not published
2Earth radius from weight difference*not published
3Cold front arrival time*not published
4Hemisphere slide and falling body*not published
5Gas cylinder recoil in space*not published
6Mass on trough with hanging weight*not published
7Bubble hanging from ceiling*not published
8Drilling through Flat Earth*not published
9Tearing toilet paper roll*not published
10Scattering shift and potential shape*not published
11Gravitational attraction of cylinder halves*not published
12Problem 12not published
13Ellipsoid floating equilibria*not published
14Rotating planet ocean shape*not published
15Hamiltonian with tangent potential*not published
16Mutual inductance of toroidal coil*not published
17Magnetic field change at center*not published
18Classical spins on a cube*not published
19Scalar field scattering cross section*not published
20Anisotropic mass from angular momentum*not published
21Phase transition in 2D gas*not published
22Flat universe with exotic equations of state*not published
23Hubbard model auxiliary field*not published
24Quantum cannonball wavefunction optimization*not published

2025

Hungary

Problems25 problemsProblems

1Inelastic mirror world*not published
2Bead collision chain with restitution*not published
3Cutting a curve for time gain*not published
4Le Sage gravity model*not published
5Drawer with broken roller*not published
6Floating cylinder with varying density*not published
7Hamiltonian with r Φ(p)*not published
8Thermometer in temperature gradient*not published
9Dispersion for moving observer*not published
10Elastic wave in layered half-space*not published
11Caustics in elastic cylinder*not published
12Morse lattice dispersion relation*not published
13Reflection from a large sphere*not published
14Force between two charged spheres*not published
15Resistance in perturbed square grid*not published
16Magnetic dipole near star frame*not published
17Compass in solenoid field*not published
18Spin dynamics under nonlinear Hamiltonian*not published
19Radon detector response analysis*not published
20Ecosystem stability under radiation*not published
21Shuttled harmonic trap ground-state probability*not published
22Lattice z(n) gauge theory simulation*not published
23Torus topologies in spin glass*not published
24Entanglement and unitarity of qubit states*not published
25Photon rocket to Zeta Monoculi*not published

2024

Hungary

Problems32 problemsProblems

1Earth radius from mountain photo*not published
2Train in a circular tunnel*not published
3Two-seat swing chaos*not published
4Satellite altitude from all-sky images*not published
5Cord on adjustable slopes*not published
6Half-tube and rolling cylinder*not published
7Eratosthenes-style Earth measurement*not published
8Lifting a rope with friction*not published
9Rotating spring-mass chain*not published
10Planet on off-center circle*not published
11Earth radius from free fall*not published
12Optimal incline shape problem*not published
13Tidal torque on rigid body*not published
14Ion-molecule reaction cross section*not published
15Sierpinski carpet pull*not published
16Langevin friction of heavy mass*not published
17Caustics in elliptical cylinder*not published
18Solar panel atmospheric absorption*not published
19Dielectric cube in electric field*not published
20Relativistic round trip*not published
21Rindler coordinates and wave equation*not published
22Half field lines to two spheres*not published
23Horseshoe magnet vector potential*not published
24Rotating wire loop in magnetic field*not published
25Spin waves in ferromagnetic molecule*not published
26Quantum ferromagnetic molecule excitations*not published
27Spectrum of a spin chain Hamiltonian*not published
28Epr correlations under data permutation*not published
29Landau levels for generalized Dirac*not published
30Quasi-spin Heisenberg evolution*not published
31Epr function not a Wigner function*not published
32Heisenberg Hamiltonian diagonalization*not published

2023

Hungary

Problems33 problemsProblems

1Tensegrity table rope cut*not published
2Battle model dynamics*not published
3Solar panel atmospheric absorption*not published
4Problem 4not published
5Ball on rotating racket*not published
6Cylinder slip to roll*not published
7Rotating Earth gravity train*not published
8Hoop with mass on accelerating belt*not published
9Drag laws in drop towers*not published
10Electric restricted three-body problem*not published
11Time-varying G and Earth's orbit*not published
12Dyon and electron circular orbit*not published
13Sliding on a square prism planet*not published
14Wheel–object interaction regimes*not published
15Optimal production scheduling*not published
16Twist and curl of elastic band*not published
17Beer mug emptying and spill*not published
18Modified Jurin's law in tubes*not published
19Sloshing in stratified cocktail*not published
20Two-Component Phase Coexistence*not published
21Dissipative force entropy inequality*not published
22Light beam in spherical atmosphere*not published
23Reconstruct resistor network from resistances*not published
24Dipole oscillation in triangular loop*not published
25Magnet on ferromagnetic table*not published
26Falling ring above current loop*not published
27Magnetic field of a cubic planet*not published
28Particle in relativistic scalar field*not published
29Relativistic fall in scalar field*not published
30Relativistic rocket with fuel economy*not published
31Sudden magnetic field change*not published
32Entanglement of triplet state*not published
33Supersonic ambulance car sounds*not published

2022

Hungary

Problems28 problemsProblems

1Semi-cycloid slope friction*not published
2Lagrangian equations of motion*not published
3Optimal fuel consumption on hilly road*not published
4Football bouncing off wall and ground*not published
5Pendulum with changing length*not published
6Ring on rotating rod*not published
7Constant-force roller-coaster loop*not published
8Skate on inclined plane*not published
9Swinging wire letters elte*not published
10Triatomic molecule vibrations*not published
11Ocean depth on planar planet*not published
12Fresnel zone plate focusing*not published
13Oscillations near charged triangle*not published
14Iron sphere in solenoid inductance*not published
15Terminal fall through polygonal pipe*not published
16Field lines in flat solenoid*not published
17Rectangular circuit with transmission delay*not published
18Current density in conical shell*not published
19Relativistic Kepler's third law*not published
20Optimized perturbation for quartic oscillator*not published
21Normalization of squeezed coherent states*not published
22Gaussian convex combinations density operators*not published
23Relative entropy of Gaussian states*not published
24Black holes in mirrored cavities*not published
25Scalar field metric and curvature*not published
26Cellular automaton wave propagation*not published
27Variational Ising chain free energy*not published
28Supersonic ambulance Doppler puzzle*not published

2020

Hungary

Problems28 problemsProblems

1Sis epidemic model dynamics*not published
2Driven oscillator with changing amplitude*not published
3Eötvös gravitational constant experiment*not published
4Repeated launches with drag*not published
5Room heating and cooling curves*not published
6Mopping bucket tilt angle*not published
7Green's function for driven particle*not published
8Tidal locking energy dissipation*not published
9Tidal locking dynamics*not published
10Problem 10not published
11Thunder clap and murmur*not published
12Core oscillations in fluid*not published
13Magnetic dipole collision time*not published
14Charge relaxation during collision*not published
15Entropy increase in tea mixing*not published
16Grating with random slit widths*not published
17Rotated grating diffraction*not published
18Relativistic orbits in scalar fields*not published
19Quantum particle in linear potential box*not published
20Sudden frequency change of oscillator*not published
21Electron specific heat at constant Fermi energy*not published
22Adiabatic demagnetization cooling curve*not published
23Magnetic translation operators on lattice*not published
24Free particle in expanding universe*not published
25Yukawa O(4) counterterm anomaly*not published
26Depth statistics of Lake Balaton*not published
27FlatEarth dimensions from local measurements*not published
28Forces on a ladder*not published

2019

Hungary

Problems50 problemsProblems

1Eötvös pendulum between two masses*not published
2Eötvös gravitational torque maximization*not published
3Molecular size from capillary waves*not published
4Pendulum clock at latitude*not published
5Ballistic missile elliptical trajectories*not published
6Aircraft skid marks length*not published
7Two masses on a filament with nail*not published
8Rimless wheel friction limit*not published
9V-shaped ski climb*not published
10Ocean freezing and Earth's rotation*not published
114D symmetric top motion*not published
12Reflectionless rope termination*not published
13Damped elastic rod modes*not published
14Sudden audibility of high planes*not published
15Underwater ring depth measurement*not published
16Underwater wave steepness measurement*not published
17Reflective surface for given caustic*not published
18Black hole planet sky and water*not published
19Full Moon vs Daytime Sky*not published
20Rotating planet surface temperature*not published
21Laser heating of a solid*not published
22Compression of segmented gas container*not published
23Dipole-skinned beast hair repulsion*not published
24Pressure in rarefied gas sphere*not published
25Rotational states of a molecule*not published
26Dipole field line equation*not published
27Charge density on Cornu spiral*not published
28Rotating sphere capacitance*not published
29Voltage in cylindrical shell*not published
30Multipole radiation from Platonic solids*not published
31Force between skewed wires*not published
32Ellipse geometry from resistance*not published
33Constant current on a 3-torus*not published
34Relativistic bicycle wheel photo*not published
35Relativistic starship with constant acceleration*not published
36Dark photon decay chain*not published
37Shear viscosity in relativistic flow*not published
38Eigenvalues of energy-momentum tensor*not published
39Nonlinear electrodynamics plane waves*not published
40Building Einstein-Hilbert action*not published
41Cosmological phase plane analysis*not published
42Gravitational wave energy loss*not published
43Quantum particle with internal degree*not published
44Quantum hopping on mollusc legs*not published
45Scale-invariant inverse-square potential*not published
46Sierpinski fractal phonons and spins*not published
47N electrons coupled to a mode*not published
48Entanglement near a black hole*not published
492PI Effective Potential Expansion*not published
50Raising a satellite daily*not published

2018

Hungary

Problems33 problemsProblems

1Fractal gummy ball rolling*not published
2Roundabout time loss*not published
3Pulled mass on rough plane*not published
4Boomerang return radius*not published
5Chain of pendulums with geometric masses*not published
6Leaning rod snap condition*not published
7Ring of satellite droplets*not published
8Air bubble in rotating cylinder*not published
9Stone skipping bounce count*not published
10Rain drag on a car*not published
11Air well water yield*not published
12Why glacier ice is harder*not published
13Solid argon vs carbon dioxide*not published
14Heating a body with heat engines*not published
15Free energy for nicotine-water phase diagram*not published
16Critical thickness of Si film*not published
17Cork viewed through lens*not published
18Caustics from sinusoidal water waves*not published
19Birefringent wedge capacitor*not published
20Charged and neutral ball collision*not published
21Maximizing electric field from dipole surface*not published
22Visible light beam from moving rocket*not published
23Electron photon pair production*not published
24Rocket with constant proper acceleration*not published
25Em wave in moving glass*not published
26Infinite well wavefunction error*not published
27Angular momentum uncertainty state*not published
28Exact evolution of the Dicke model*not published
29Slow light in two-level gas*not published
30Quantum dissipation purity condition*not published
31Covariant weight in general relativity*not published
32Balloon falling into black hole*not published
33Fall through Earth shapes*not published

2017

Hungary

Problems40 problemsProblems

1Tricolore flag color proportions*not published
2Echo in hemispherical hall*not published
3Rain waves on a ramp*not published
4Coin flipping dynamics*not published
5Multiple reflections between two spheres*not published
6Central potentials with peculiar orbits*not published
7Norton dome classical and quantum*not published
8Free-end chain normal modes*not published
9Work between poles of two-hemisphere sphere*not published
10Rolling globule oscillation bounds*not published
11Young modulus from rod collision*not published
12Planet orbit under Lorentz boost*not published
13Oscillator coupled to continuum*not published
14Chladni pattern synthesis limits*not published
15Capillary rise dynamics*not published
16Oscillation in tetrahedral charge field*not published
17Four-point resistance on composite sheet*not published
18Heart-aorta-arteries flow model*not published
19Melting cylinder in air*not published
20Tungsten lamp brightness vs temperature*not published
21Negative index slab imaging*not published
22Lunar laser ranging retroreflector*not published
23Electron focusing in crt*not published
24Joint decay of two atoms*not published
25Antisymmetric coupling tensor action*not published
26Relativistic Hubble flow generalization*not published
27Synchronous satellite clock altitude*not published
28Magnetic field and canonical momentum*not published
29Spin in rotating magnetic field*not published
30Spin pair under sudden perturbation*not published
31Spin-2 time reversal invariant state*not published
32Quantum measurement and collapse*not published
33Harmonic oscillator in coherent basis*not published
34Quantum particle with dyadic Hamiltonian*not published
35Charged polygon Stark splitting*not published
36Photon numbers in hhg model*not published
37Hierarchical four-black-hole stability*not published
38Decreasing gravitational wave frequency*not published
39Ising model on hyperbolic lattice*not published
40Refractive index of vibrarium gas*not published

2016

Hungary

Problems36 problemsProblems

1Tractor wheel size evolution*not published
2Rope slingshot with two masses*not published
3Symmetric ladder collapse time*not published
4Stacked bouncing balls launcher*not published
5Magnet in rotating tube*not published
6Mass point and quarter-circle wall*not published
7Loaded dice properties*not published
8Baumgartner's jump analysis*not published
9Doppler shift from moving ambulance*not published
10Refrigerator in insulated kitchen*not published
11Momentum of rising air in heated tube*not published
12Infinite periodic resistor network*not published
13Resistor lattice width measurement*not published
14Voltage between points on disc*not published
15Equipotentials in anisotropic dielectric*not published
16Mercury droplet in electric field*not published
17Vanishing field charge configurations*not published
18Electrons in parabolic nanotube*not published
19RGB sky at dawn*not published
20Corner cube reflection intensity*not published
21Moving source sound intensity*not published
22Photovoltaic rod and moving plate*not published
23Relativistic orbits in scalar field*not published
24Gravitational wave circularization time*not published
25Energy-time uncertainty in a box*not published
26Two electrons in parabolic nanotube*not published
27Adiabatic quantum pump charge*not published
28Tight-binding chain transmission*not published
29Last nucleus decay time*not published
30Normal ordering change for scalar field*not published
31Temperature of visible oscillator*not published
32Scalar decay lifetime formula*not published
33Negative temperature spin system*not published
34Ward identity and gauge invariance*not published
35Aether debate in condensate*not published
36Vertical projectile and Earth's rotation*not published

2015

Hungary

Problems31 problemsProblems

1Shadowless building design*not published
2Plummet deviation on planet*not published
3Body on inclined plane with friction*not published
4Sand-covered region on sphere*not published
5Rotating dumbbell pair dynamics*not published
6Second variation of action*not published
7Damped wave equation solution*not published
8Elliptic cycle efficiency limits*not published
9Spring thermodynamics and Carnot efficiency*not published
10Focusing sunlight below sun temperature*not published
11Force on charge near grounded torus*not published
12Voltage between corners of plate*not published
13Conductivity pattern in Rubik's cube*not published
14Magnetic field of spherical shell circuit*not published
15Rotating charge distribution magnetic field*not published
16Anisotropic Lorentz transformations*not published
17Eigenvalue problem of field tensor*not published
18Scalar gravity free fall*not published
19Equivalence principle and local measurements*not published
20Static spacetime Lagrangian reduction*not published
21Bungee jumping into a black hole*not published
22Kerr geodesics through wormhole*not published
23Cohesive energy vs coordination number*not published
24Uncertainty equality for Hermitian matrices*not published
25Scattering off a delta potential*not published
26Hydrogen tunneling on a lattice*not published
27Entangled spins and measurement correlations*not published
28Fokker-Planck from path integrals*not published
29Large-N scalar field theory renormalization*not published
30Quantum harmonic oscillator*not published
31Sky temperature vs zenith angle*not published

2014

Hungary

Problems35 problemsProblems

1Unclear*not published
2Bicycle power measurement*not published
3Bouncing on lunar slope*not published
4Oscillating half‑disk pendulum*not published
5Libration of a tidally locked moon*not published
6Solar solstice sunrise anomaly*not published
7Evaporating exoplanet dust tail*not published
8Stability of anharmonic oscillator*not published
9Cable shape: Equilibrium vs variational*not published
10Stagnation points on Kutta-Zhukovsky airfoil*not published
11Minimal surface between rings*not published
12Cylinder viewed through lens*not published
13Perfect imaging and wave optics*not published
14Laser tweezer trapping of nano-ball*not published
15Infinite resistor strip resistance*not published
16Charged wire between grounded plates*not published
17Current flow on a sphere*not published
18Grounded cavity potential*not published
19Anisotropic cuboid resistance*not published
20Magnet bending a clamped rod*not published
21Magnet falling in steel pipe*not published
22Spin waves in magnetic lattice*not published
23Piston with friction between gases*not published
24Relativistic particle exchange*not published
25Vertical throw in Schwarzschild field*not published
26Spaceships falling into a black hole*not published
27Swiss cheese hollow sphere*not published
28Quantum particle in inverse-square potential*not published
29Squeezed oscillator states*not published
30Fractal dimension of single-particle operators*not published
31Perturbative φ³-φ⁴ field theory*not published
32Identical particles on quotient space*not published
33Problem 33not published
34Sand particle size from satellite*not published
35Solar System velocity from sdss*not published

2013

Hungary

Problems31 problemsProblems

1Microwave milk warming recipe*not published
2Free-fall speed record comparison*not published
3Elastic collision matrix eigenstates*not published
4Pulley chain accelerations*not published
5Evaporating planet's orbit evolution*not published
6Optimal bicycle energy strategy*not published
7Centrifugal potential sign paradox*not published
8Fermat principle with directional index*not published
9Perturbed orbit perihelion shift*not published
10Cone rolling on inclined slope*not published
11Vibrating cantilever beam frequencies*not published
12Rope sagging between two pulleys*not published
13Mercury droplet on glass*not published
14Largest hanging droplet height*not published
15Rotating self-gravitating liquid droplet*not published
16Sound waves in moving frames*not published
17Infinite triangular LC chain*not published
18Charged wire near grounded plate*not published
19Charged cylinder falling onto grounded plane*not published
20Dipole near superconducting sphere*not published
21Two compasses in Earth's field*not published
22Magnetic dipole falling through ring*not published
23Classical spin waves on honeycomb lattice*not published
24Free fall in Nordström gravity*not published
25Two rotated grids diffraction*not published
26Oscillator with periodic potential*not published
27Finite matrices in quantum theory*not published
28Dispersion on wrapped lattice*not published
29Electron in a 1D box*not published
30Landau levels in two-material slab*not published
31Photon pressure on relativistic spaceship*not published

2012

Hungary

Problems29 problemsProblems

1UFO parabolic trajectory near Sun*not published
2Bunk bed for a restless sleeper*not published
3Leg fluttering frequency ratio*not published
4Ball rolling on tilted rotating disk*not published
5Rotating space sling*not published
6Cylinder in coaxial hole*not published
7Mass on elastic thread*not published
8Gravitational scattering by binary system*not published
9Velocity-dependent Lagrangian dynamics*not published
10Oscillator with memory*not published
11Chain of masses with two spring constants*not published
12Steel rod struck at end*not published
13Stirling engine efficiency analysis*not published
14Flawed entropy maximization argument*not published
15Problem 15not published
16Charge near conducting cylinder*not published
17Mutual inductance of crossed toroids*not published
18Power line radiation losses*not published
19Identifying circular polarizers*not published
20Variable speed of light and lensing*not published
21Moving observer and star mass*not published
22Determining an unknown spin-1 state*not published
23Electron spin in helical magnetic field*not published
24GaAs atomic packing ratio*not published
25Band structure from transfer matrix*not published
26Muon accelerator survival and Higgs*not published
27Electron momentum distribution in magnetic mirror*not published
28Star-graph Ising magnetization limit*not published
29Baumgartner's supersonic fall*not published

2011

Hungary

Problems42 problemsProblems

1Gummy berry chain reaction*not published
2Glide distance on asteroid*not published
3Yo-yo unwinding motion*not published
4Locating house from sunrise times*not published
5Ball in vertical tube*not published
6Skater on rotating disk*not published
7Charged particle in cloud chamber*not published
8Tidal torque on asteroid*not published
9Barrel rolling on sloped rails*not published
10Sun paths and seasons on Trundler*not published
11Synchronous satellite coverage fraction*not published
12Supersonic boom from accelerating jet*not published
13Underwater star trajectories from refraction*not published
14Cherenkov wave front from circular motion*not published
15Delayed boundary chain spectrum*not published
16Triangular lattice with missing spring*not published
17Rotating sphere elastic deformation*not published
18Gas bubble at vessel bottom*not published
19Navier-Stokes symmetry under blowing*not published
20Ultrasonic disk diffraction zero*not published
21Magnetic escapement design*not published
22Charged spinning ball in magnetic field*not published
23Transmission through graded-index plate*not published
24Antimatter rocket optimization*not published
25Nordström gravity Kepler orbit*not published
26Hypergravitational force and relativistic motion*not published
27Ring gravity and Bohr orbits*not published
28Positronium size comparison*not published
29Magic numbers of harmonic oscillator*not published
30Dimerized chain tight-binding model*not published
31Electron in harmonic trap with magnetic field*not published
32Massless fermion scattering on spin*not published
33Generalized Dirac Landau levels*not published
34Positronium annihilation photon spectrum*not published
35Problem 35not published
36Gas effusion through a hole*not published
37Isotope identification in cloud chamber*not published
38Lorentz-violating particle decays*not published
39Neutrino time delay in gravity*not published
40Problem 40not published
41Straight roller coaster to orbit*not published
42Earth climate model stability*not published

2010

Hungary

Problems35 problemsProblems

1Locating a moving target*not published
2Iceball cargo sliding between poles*not published
3Max tension on inclined plane*not published
4Skier jump vs slide speed*not published
5Drag force from pendulum decay*not published
6Terminal velocity on a track*not published
7Stability of rolling hoop*not published
8Cable shape for suspension bridge*not published
9Stable hanging of rigid body*not published
10Rotating chain on a gear*not published
11Tilting body detaching from table*not published
12Stability of a card tower*not published
13Dam collapse tension estimate*not published
14PET bottle polygon energy levels*not published
15Chained toroidal planets*not published
16Elastic waves in a spherical bell*not published
17Polarization conversion in anisotropic crystals*not published
18Droplets on water surface*not published
19Oxygen–nitrogen mixture compression*not published
20Combined cycle Carnot proof*not published
21Eccentricity and climate change*not published
22Circular field line of two wires*not published
23Critical velocity for alpha particles near coil*not published
24Golden loxodrome on glass orb*not published
25Rainbow on planet Alexander*not published
26Caustics of a water droplet*not published
27Einstein's letter bomb weight*not published
28Voronoi polyhedron edge relation*not published
29Wiedemann–Franz law conditions*not published
30Light paths in spherical gravity*not published
31Spaceships falling into a black hole*not published
32Dirac billiard in a ring*not published
33Absorption spectra of quantum boxes*not published
34Semiconductor surface charge dynamics*not published
35Optimal breast feeding strategy*not published

2009

Hungary

Problems31 problemsProblems

1Flat Earth vs. Round Earth test*not published
2Rolling cube on a surface*not published
3Spaghetti swallowing force balance*not published
4Block hits coil spring*not published
5Mass-varying projectile upward motion*not published
6Amplitude-independent period potential*not published
7Gravity potential on R3 × S1*not published
8N-pendulum eigenfrequencies and continuum limit*not published
9Stiff rope over wearing edge*not published
10Debris fall on asteroid*not published
11Slow dribble from inclined plane*not published
12Smoke ring motion direction*not published
13Ice melting in saltwater vs freshwater*not published
14Pressure from Brownian motion*not published
15Problem 15not published
16Shuffle card permanence statistics*not published
17Atmospheric refraction and celestial ellipticity*not published
18Transmission through graded-index layer*not published
19Floating permanent magnets*not published
20Lawrence transformations in reductivity*not published
21Relativistic particle in fields*not published
22Eigenvalue problem of em tensors*not published
23Astronaut's cosmic reach*not published
24Semiconductor p-n junction photodetector*not published
25Lens billiard stability and quantization*not published
26Scale-invariant quantum system*not published
27Electron in gravitational box*not published
28Spinors and Minkowski space*not published
29Bec critical temperature corrections*not published
30Electron wave packet in hexagonal lattice*not published
31Sunlight bending around building*not published

2008

Hungary

Problems36 problemsProblems

1Torch orbit around Moon*not published
2ISS pass frequency variation*not published
3Lazy pedestrian crossing curve*not published
4Equilibrist on elastic rod*not published
5Bicycle stability with counter-rotating wheels*not published
6Anharmonic oscillator period corrections*not published
7Three bugs on a circle*not published
8Falling mass on prism*not published
9Elastic waves in welded cylinders*not published
10Anthropic effects on day length*not published
11Elastic layer transmission condition*not published
12Infrasound-driven box vibration*not published
13Quarter-wave tube sound trap*not published
14Sound transmission through multilayer stack*not published
15Mirage conditions and image orientation*not published
16Coin standing probability*not published
17Fake ball with two scales*not published
18Problem 18not published
19Torrent file readiness distribution*not published
20Charge of current ring in rotating frame*not published
21Resistor ladder on Möbius strip*not published
22Rolling magnets on conducting strips*not published
23Sphere in uniform field energy*not published
24Transfer matrices for magnetic focusing*not published
25Copper wire heating and quench wave*not published
26Two Suns' temperatures and entropy*not published
27Black hole falling through Earth*not published
28Filament growth stall force*not published
29Transfer matrix in continuous limit*not published
30Muon decay angular distribution*not published
31Bose-condensed trapped gas excitations*not published
32Radon diffusion from granite sphere*not published
33Niobium isotope evolution in supernova*not published
34Significance of a discovery*not published
35Black hole in cosmic background*not published
36Ancient Dawning Star orbit*not published

2007

Hungary

Problems32 problemsProblems

1Space lift jumps*not published
2Rotating sausages in hot water*not published
3Sliding spinning torus on plane*not published
4Forces in orbiting spaceship*not published
5Chain on nails with threads*not published
6Three cars with springs*not published
7Spring chain equilibrium spacing*not published
8Paint drops on a hillside*not published
9Rotating rope in space*not published
10Juggling machine stability*not published
11Hamiltonian with arbitrary momentum dependence*not published
12Earth's rotation after eruption*not published
13Windmill maximum efficiency model*not published
14Air escape from a room*not published
15Elastic modulus index symmetry*not published
16Ion trajectories in periodic electrode structure*not published
17Focusing in negative-index sphere*not published
18Random grating diffraction pattern*not published
19Mirage in Hortobágy*not published
20Band structure of layered dielectric*not published
21Minimum field in current triangle*not published
22Michelson–Morley with rockets*not published
23Modified electrodynamics with axion term*not published
24Electrostatics on a spherical universe*not published
25Nonlinear electrodynamics model*not published
26Mass measurement uncertainty*not published
27Spin polarization of reflected wave*not published
28Phase diffusion master equation*not published
29Two-particle states in a shell*not published
30Conformal invariance of massless fields*not published
31Shroud of Turin carbon dating*not published
32Problem 32not published

2006

Hungary

Problems33 problemsProblems

1Zenithal Rainbow on Geminecto*not published
2Galileo's falling object claim*not published
3Day length and dusk vs latitude*not published
4Leaning motorbike friction*not published
5Planetary motion with varying G*not published
6Released hanging string motion*not published
7Damped rocking horse acceleration*not published
82D Rutherford scattering on wire*not published
9Relativistic Rutherford scattering*not published
10Scattering on soft sphere*not published
11Oil field gravity anomaly*not published
12Sliding egg-shaped asteroid halves*not published
13Cart with pendulums drag model*not published
14Ancient Hungarian reflex bow*not published
15Oscillating branch in river*not published
16Tidal locking model*not published
17Coin attraction on water surface*not published
18Power for random wave excitation*not published
19Rotating charged sphere fields*not published
20Liquid level in heated cylinders*not published
21Climate trend statistical fluctuation*not published
22Interaction energy of point defects*not published
23Relativistic wheel center of mass*not published
24Generalized mass from Zweistein function*not published
25Burnout times in bulb circuits*not published
26Intelligent states and harmonic oscillator*not published
27Spin-dependent scattering symmetries*not published
28Half-life from five decays*not published
29Radon daughter alpha activity on filter*not published
30Spin in fluctuating magnetic field*not published
31Spin-dependent Hamiltonian motion*not published
32Squark decay mass bounds*not published
33Huge Wheel on a Meridian*not published

2005

Hungary

Problems42 problemsProblems

1Perpetual motion U-tube*not published
2Spaceship heat engine paradox*not published
3Rolling hemispherical orange paths*not published
4Projectile radar relative motion*not published
5Spider's fastest round trip*not published
6Laser through liquid tank*not published
7Dip-shaped soliton on water*not published
8Two magnets on a line*not published
9Elliptical light paths in graded medium*not published
10Galilean covariance of electrodynamics*not published
11Moving parabolic mirror image*not published
12Complex charge distributions*not published
13Electrodynamics of rotating frames*not published
14Hair curvature angle distribution*not published
15Diffusion equation paradox*not published
16Drunkard's random walk home*not published
17Tachyons relative speed*not published
18Einstein Station fuel cycle*not published
19Accelerated laser properties*not published
20Standing waves in moving medium*not published
21Muon decay momentum distribution*not published
22Expanding photon gas thermodynamics*not published
23Twin paradox on a cylinder*not published
24Spaceship time dilation mission*not published
25Black hole time dilation*not published
26Einstein's daisy orbits*not published
27Gravitational waves from neutron star*not published
28Anomalous probe acceleration vs Hubble expansion*not published
29Wormhole tidal forces*not published
30Wormhole matter properties*not published
31Schwarzschild-de Sitter black hole*not published
32Cosmic expansion and planetary orbits*not published
33Neutrino mass from uhecr Z-burst*not published
34Swiss-cheese cosmological model*not published
35Photoelectric effect and photon existence*not published
36Bose-Einstein condensation in a trap*not published
37Spin-orbit ring in magnetic field*not published
38Gauge-invariant spherical symmetry condition*not published
39Photon-mirror entanglement in interferometer*not published
40Quantized damped harmonic oscillator*not published
41Casimir and van der Waals forces*not published
42Random chain resistance*not published

2004

Hungary

Problems32 problemsProblems

1Satellite photo time and cloud altitude*not published
2Robinson's pond escape*not published
3Jet propulsion cart with water tank*not published
4Stones on spinning planet*not published
5Binary star orbit and blackbody temperature*not published
6Two protons in uniform magnetic field*not published
7Coefficient of restitution exceeding one*not published
8Bicycle wheel track relation*not published
9Packet transfer between space stations*not published
10Tensorial mass dynamics*not published
11Dumbbell planet spin-orbit exchange*not published
12Rod pendulum energy vs time*not published
13Ball in rotating water*not published
14Spinning neutron star oblateness*not published
15Wind refraction of drum sound*not published
16Relativistic motion in scalar potential*not published
17Mirror illusion vs real meteor*not published
18Doppler effect under acceleration*not published
19Relativistic Coulomb scattering cross section*not published
20Black hole tourism limits*not published
21Falling observers near black hole*not published
22Modified gravity for flat rotation curves*not published
23Quantum rigid rotor spectrum*not published
24Hamiltonian spectrum via unitary transform*not published
25Effective mass operator ordering*not published
26Spin-orbit electron in magnetic field*not published
27Adiabatic invariance in classical and quantum systems*not published
28Noncommutative quantum mechanics constraints*not published
29Zero-point phonon energy in helium*not published
30Two ion clouds collision probability*not published
31Scale-independent terrestrial distributions*not published
32Paper roll unrolling down wall*not published

2003

Hungary

Problems42 problemsProblems

1Rainfall and day length*not published
2Falling rope loop*not published
3Sliding cord with two masses*not published
4Lennard-Jones potential oscillations*not published
5Stability at Earth-Moon Lagrangian point*not published
6Two cylinders on incline*not published
7Twisted trapeze unwinding*not published
8Comet collision debris envelope*not published
9Golden asteroid gravity exponent*not published
10Wind-resistant tower shape*not published
11Drum membrane eigenfrequencies*not published
12Estimating fan lifetime*not published
13Virial theorem for homogeneous potentials*not published
14Bubbles at Liquid Interface*not published
15Tidal magnitude estimate*not published
16Gravity waves in thin atmosphere*not published
17Dipole in uniform magnetic field*not published
18Electrostatics on a spherical surface*not published
19Rotating sphere induced magnetic moment*not published
20Ampère's three coaxial circular currents*not published
21Cylindrical resistor lattice resistance*not published
22Dipole fields satisfy Maxwell equations*not published
23Oblateness of the setting Sun*not published
24Passive solar concentrator design*not published
25Moon through lexan roof*not published
26Soap bubble bright spots*not published
27Jupiter turned into a star*not published
28Nordström gravity projectile motion*not published
29Gravitational bremsstrahlung from globular cluster*not published
30Variable speed of light gravity*not published
31Loosely rigid body on curved manifold*not published
32Radon diffusion from radium sphere*not published
33Lithium-8 nuclear collision*not published
34Jahn-Teller effect in harmonic well*not published
35Electron in a ring with Zeeman term*not published
36Qubit decoherence in fluctuating metric*not published
37Quantum secret sharing*not published
38Light sabre feasibility*not published
39Parallel computer ring performance*not published
40Airing schedule for a room*not published
41Detecting intelligence from trajectories*not published
42Moving ship mirage*not published

2002

Hungary

Problems33 problemsProblems

1Hollywood bomb circuit*not published
2Sliding body stopping direction*not published
3Unwinding thread with swinging mass*not published
4Detachment of rolling cylinder*not published
5Force to separate gravitating hemispheres*not published
6CD sliding and spinning stop*not published
7Two electrons in magnetic field*not published
8Hamiltonian with position-dependent speed*not published
9Mechanics in hyperbolic plane*not published
10Pulled semi-infinite spring chain*not published
11Non-local elastic continuum waves*not published
12Drum membrane with hole*not published
13Frequency shift of open pipe hole*not published
14Candle crater shape*not published
15Frozen meat in microwave*not published
16Cloud chamber temperature profile*not published
17Infinite lattice with removed edge*not published
18Charged rod between grounded planes*not published
19Superconducting coil in a tube*not published
20Superposed circular and linear gratings*not published
21Polarizers in Mach-Zehnder interferometer*not published
22Michelson-Morley at arbitrary angle*not published
23Twin paradox with acceleration limit*not published
24Relativistic Kepler precession and scattering*not published
25Relativistic interstellar ramjet*not published
26Gravitational wave supernova limit*not published
27Black hole evaporation in cosmic background*not published
28Quantize system from Problem 7*not published
29Charged particle in dipole field*not published
30Schrödinger–Kostin damped equation*not published
31Electron-hole reaction equilibrium*not published
32Optimal driving near traffic lights*not published
33Portfolio optimization under risk*not published

2001

Hungary

Problems34 problemsProblems

1Walking by watch hand*not published
2Disk pulled on carpet*not published
3Y-bough log stack support*not published
4Blind aircraft 1g descent*not published
5Ant vs. Falling rod*not published
6Eccentric circular orbit*not published
7Hiker's optimal path problem*not published
8Dove on a cable*not published
9Iron rod in concrete*not published
10Balloon inflation shape*not published
11Copper vs iron pipe capacity*not published
12Two images in flashlight mirror*not published
13Thomson model electron configurations*not published
14Maximal field from superconducting magnet*not published
15Bimetallic capacitor with hysteretic resistor*not published
16Two electrons in a magnetic field*not published
17Ring falling onto a magnet*not published
18Periodic dielectric stack dispersion*not published
19Second law paradox analysis*not published
20Funnel shape for constant pV*not published
21Relativistic scalar gravity model*not published
22Particle in a tensor field*not published
23Hypergravity equation of motion*not published
24Two masses in expanding universe*not published
25Two spin-half dipoles on a rod*not published
26Landau levels with hard wall*not published
27Stability of H− and H−− ions*not published
28Planar rotator thermodynamics*not published
29Perturbed harmonic oscillator states*not published
30Time-dependent oscillator Bogoliubov transformation*not published
31Quantum crystal variational model*not published
32Galilean boost phase superposition*not published
33Gluon exchange in proton collisions*not published
34Neutrino mass from uhecr protons*not published

2000

Hungary

Problems37 problemsProblems

1Ball on a dog's tail*not published
2Perpetual motion machine under water*not published
3Catapult bungee ejection safety*not published
4Satellite litter chain reaction*not published
5Crossing a moving walkway*not published
6Pearl on string between supports*not published
7Rubber ball on turntable*not published
8Rotating rope shape*not published
9Hour-glass on a rod*not published
10Elliptic membrane frequency shift*not published
11Harmonic trap gas eigenmodes*not published
12Towel folding kink criteria*not published
13Sugar accumulation in tea*not published
14Effusion between two tanks*not published
15Efficiency with conductive heat transfer*not published
16Doppler torque on a cogwheel*not published
17Resistance lattice on cylinder*not published
18Magnetic field at cube centre*not published
19Capacitor discharge via parallel wires*not published
20Friction between moving dielectric sheets*not published
21Gaussian packet in toroidal waveguide*not published
22Massive charge scattering plane wave*not published
23Superconducting ring resistance limit*not published
24Aircraft shadow rings*not published
25Uhecr multiplets and sources*not published
26Gaussian mixture model test*not published
27Illumination of a relativistic cube*not published
28Non-relativistic gravity theory*not published
29Quantised coupled oscillator system*not published
30Electron in divided box*not published
31Epr experiment record*not published
32Bell inequality with detector settings*not published
33Composite boson from fermions*not published
34Driven monatomic chain energy transfer*not published
35Plasma expansion in magnetic field*not published
36Entropy and cleaning a room*not published
37Spin measurement survival strategy*not published

1999

Hungary

Problems34 problemsProblems

1Swing parametric resonance*not published
2Slingshot bullet with air resistance*not published
3Rod detaching from wall*not published
4Mercury in L-shaped tube*not published
5Point charge near fixed dipole*not published
6Drag force with constant kinetic energy*not published
7Hamiltonian trajectory classification*not published
8Colliding prisms contact time*not published
9Driving side and day length*not published
10Tidal lunar recession estimate*not published
11Water surface in rotating glass*not published
12Viscous vortex solutions*not published
13Torque between two magnetic dipoles*not published
14Resistance without breaking circuit*not published
15Black box capacitor energy*not published
16Rotating charged rod angular momentum*not published
17Infinite grid resistance*not published
18Adiabatic expansion against external pressure*not published
19Black disk in cbr*not published
20Coin toss chaos*not published
21Stock random walk profit distribution*not published
22Metastable state dynamics*not published
23Asymptotic series for scattering wavefunction*not published
24Airy wave packet in linear potential*not published
25Motion on upper half-sphere*not published
26Quantized k-fold pendulum*not published
27Lattice Laplacian and Spin Spectrum*not published
28Two-site Hubbard model*not published
29Atom crossing Fabry–Perot cavity*not published
30Spin measurement reversibility model*not published
31Carbon nanotube band gap*not published
32Infinite-dimensional anisotropic oscillator*not published
33Tunnel transit time loss*not published
34Tiredness and work efficiency*not published

1998

Hungary

Problems35 problemsProblems

1Fermentation barrel heat limit*not published
2Images between parallel mirrors*not published
3Frozen windscreen east side*not published
4Broomstick sliding against wall*not published
5Maximal stable brick tower*not published
6Displacement from strain tensor*not published
7Tympanic membrane shape and hearing*not published
8Cost of Red Blood Cells*not published
9Raindrop instability on eaves*not published
10Drop formation from pipette*not published
11Density waves in sand*not published
12Stability of a ring of satellites*not published
13Force between charged disks*not published
14Maximal inductance of folded wire*not published
15Hypercomplex electrodynamics action*not published
16Photon rocket race in Minkowski space*not published
17Rocket rod contraction paradox*not published
18Rocket ride through cosmological models*not published
19Gravity in 2+1 dimensions*not published
20Eigenvalue spectrum of coupled oscillator*not published
21Classical vs quantum uncertainty*not published
22Quantization and factor-ordering in curved space*not published
23Cooper pairs and Pauli principle*not published
24Coherent states of plane rotator*not published
25Two bosons in a box*not published
26Commuting operators for trapped Bose gas*not published
27Collisionless thermal equilibrium*not published
28Thermion gas equations of state*not published
29Mean-field Ising chain approximation*not published
30Spiral spin chain with impurity*not published
31Fermi gas with interactions*not published
32Bose gas in harmonic trap*not published
33Superfluid helium thermography*not published
34Antenna vectors and coupling constant*not published
35Roland's sword blow*not published

1997

Hungary

Problems42 problemsProblems

1Sun-following paths on Earth*not published
2Fireball in a lake*not published
3Spinning pebble reversal*not published
4Maximum prey size for a macrophage*not published
5Chain lifting over glass rim*not published
6Effervescent tablet dissolution*not published
7Small perturbations on hanging chain*not published
8Seasonal Earth angular velocity change*not published
9Three compressed elastic balls*not published
10Unrolling hose hoop dynamics*not published
11Folding a beer bottle cap*not published
12Sound transmission through ear*not published
13Swinging lift design*not published
14Yogi's breathing air displacement*not published
15Shower water temperature dynamics*not published
16Neumann equation for foam bubbles*not published
17Liquid surface in rotating vessel*not published
18Mystery Black Box Water Level*not published
19Yield criteria equivalence in 2D*not published
20Spherical vacuum bubble collapse*not published
21Water trapped in grape cluster*not published
22Symmetry and continuity equation*not published
23Buckling of rotating rod*not published
24One-way light speed measurement*not published
25Dissipative continuity in relativistic hydrodynamics*not published
26Solar cooling timescale estimate*not published
27Emission frequency in random field*not published
28Bogomolny equations finite energy*not published
29Partition functions of gas and rotators*not published
30Gas expansion and indistinguishability*not published
31Virial theorem for helium atom*not published
32Random flight in weightlessness*not published
33Classical spin square ground state*not published
34Singular inverse-square Hamiltonian*not published
35Supertransparent scattering potential*not published
36Fullerene C60 tight-binding energy levels*not published
37Decoherence of a heavy particle*not published
38Conductance quantization in nano-wires*not published
39Conductivity in a 2D quantum trough*not published
40Muon background in Gran Sasso*not published
41Newerton mechanics and conservation laws*not published
42Quantum harmonic oscillator*not published