List

VN TST Problems and Solutions

The test that picks Vietnam's IPhO and APhO teams from the best VPhO scorers: two written papers on consecutive days, with experiment-design problems among the theory.

2022

Vietnam

Day 15 problemsProblemsSolutions
  • 1Ball striking a three-mass hinged system*not published
  • 2Piezoelectric quartz plate vibrations*not published
  • 3Image charges for sphere and plane*not published
  • 4Cartesian oval refracting surfaces*not published
  • 5Classical electron model of dispersion*not published
Day 25 problemsProblemsSolutions
  • 6Rotating springs in zero gravity*not published
  • 7Heat conduction between coaxial cylinders*not published
  • 8Paramagnetic susceptibility and ferromagnetism*not published
  • 9Bohr-Sommerfeld quantization of elliptic orbits*not published
  • 10Mechanical black box with hidden masses*not published

2021

Vietnam

Day 15 problemsProblemsSolutions
  • 1Ball rolling on a rotating turntable*not published
  • 2Dissociating hydrogen and hurricane Carnot cycle*not published
  • 3Moving capacitor plates and bouncing plate*not published
  • 4Lunar eclipse duration and solar furnace*not published
  • 5Debye heat capacity of solids*not published
Day 25 problemsProblemsSolutions
  • 6Crate on roller conveyor tipping over*not published
  • 7Bose gas condensation and evaporative cooling*not published
  • 8Magnetic-charge model of solenoid and magnet*not published
  • 9Fraunhofer pattern of three unequal slits*not published
  • 10Leaky capacitor parameters and source frequency*not published

2019

Vietnam

Day 15 problemsProblemsSolutions
  • 1Centrifugal speed governor*not published
  • 2Brownian motion as a random walk*not published
  • 3Charged soap bubble and floating sphere*not published
  • 4Optical fiber attenuation, dispersion and splitters*not published
  • 5Kaon-proton reaction threshold and decays*not published
Day 25 problemsProblemsSolutions
  • 6Mechanical automatic toilet flush*not published
  • 7Heat loss from buried pipe*not published
  • 8Leaky ladder network and cable*not published
  • 9Einstein coefficients and laser gain*not published
  • 10Lamp filament emissivity exponent and size*not published

2018

Vietnam

Day 15 problemsProblemsSolutions
  • 1Pulley-driven mass on pivoted rod*not published
  • 2Thermodynamics of a paramagnet*not published
  • 3Electric dipole and point charge orbits*not published
  • 4Photon gas and satellite temperature*not published
  • 5Quantum ideal gas statistics*not published
Day 25 problemsProblemsSolutions
  • 6Kelvin wake angle behind a boat*not published
  • 7Two sliding rods on magnetic rails*not published
  • 8Radiation pressure and moving-mirror reflection*not published
  • 9Isotope shift and nuclear binding energy*not published
  • 10Temperature dependence of wire resistance*not published

2017

Vietnam

Day 16 problemsProblemsSolutions
  • 1Rutherford scattering hodograph and perturbation*not published
  • 2Statistical polarization of a polar dielectric*not published
  • 3Relativistic transformation of force*not published
  • 4Charged rotating cylinder with falling mass*not published
  • 5Liquid mercury mirror telescope*not published
  • 6Hydrogen ground-state wavefunction*not published
Day 26 problemsProblemsSolutions
  • 7Ballistic rocket and solar sail escape*not published
  • 8Heating and melting of fuse wire*not published
  • 9Graphene resistor network and four-probe measurement*not published
  • 10Electron motion and radiation in undulator*not published
  • 11Interference from a trapezoidal biprism*not published
  • 12Spring mass and shear modulus*not published

2016

Vietnam

Day 16 problemsProblemsSolutions
  • 1Ball hitting a hinged three-rod chain*not published
  • 2Refrigerator cycle with van-der-Waals air*not published
  • 3Magnet levitation and copper-tube braking*not published
  • 4Coupled LC oscillator modes*not published
  • 5Focusing surface and graded-index medium*not published
  • 6Cosmic-ray muons and muonic hydrogen*not published
Day 26 problemsProblemsSolutions
  • 7Hinged rods with spring against wall*not published
  • 8Doppler and natural sodium line broadening*not published
  • 9Hidden momentum in a current loop*not published
  • 10Gravitational lensing and its optical analogue*not published
  • 11Single-slit diffraction and rainbow optics*not published
  • 12Refractive index of a liquid*not published

2015

Vietnam

Day 16 problemsProblemsSolutions
  • 1Cylinder on rails pulled by weight*not published
  • 2Radiogenic heating of a planet*not published
  • 3Charge in magnetic and quadrupole fields*not published
  • 4Grating with geometrically shrinking slits*not published
  • 5Relativistic neutral pion decay distributions*not published
  • 6Alpha emitter in a spherical capacitor*not published
Day 26 problemsProblemsSolutions
  • 7Raindrop growing in a cloud*not published
  • 8Boiling water under a cooled lid*not published
  • 9Charged particle near a solenoid*not published
  • 10Light forces on a transparent sphere*not published
  • 11Thermodynamics of a photon gas*not published
  • 12Measuring capacitance with an LED*not published

2014

Vietnam

Day 16 problemsProblemsSolutions
  • 1Spring-linked balls in perpendicular grooves*not published
  • 2Spinning disk landing on two-friction floor*not published
  • 3Conducting gas column in gravity*not published
  • 4Proton focusing by a magnetic lens*not published
  • 5Liquid-drop and shell model binding energy*not published
  • 6Alpha track and the uncertainty principle*not published
Day 25 problemsProblemsSolutions
  • 7Cylinder on an accelerated plank*not published
  • 8Compressibility and sound in real gas*not published
  • 9Particle trapping in Earth's magnetic dipole*not published
  • 10Mirage ray paths over hot road*not published
  • 11Viscosity from annular pipe flow*not published

2013

Vietnam

Day 16 problemsProblemsSolutions
  • 1Sphere hanging from two pulleys*not published
  • 2Temperature-compensated mercury pendulum*not published
  • 3Point charge near a grounded sphere*not published
  • 4Apparent width of a thermometer column*not published
  • 5Relativistic rocket with constant proper acceleration*not published
  • 6Bohr hydrogen in weak magnetic field*not published
Day 26 problemsProblemsSolutions
  • 7Rotating massive spring with end mass*not published
  • 8Adiabatic demagnetization and central-field gas*not published
  • 9RL circuit transients with two inductors*not published
  • 10Laser force on graded-index prism*not published
  • 11Gravity-gradient stabilized dumbbell satellite*not published
  • 12Coil resistance and inductance by bridge*not published

2012

Vietnam

Day 16 problemsProblemsSolutions
  • 1Spacecraft hyperbolic flyby and landing*not published
  • 2Evaporation of a suspended water droplet*not published
  • 3Switched LC circuit with diode*not published
  • 4Radiation pressure on mirrors and spheres*not published
  • 5Superconducting sphere in a magnetic field*not published
  • 6Neutron moderation by elastic scattering*not published
Day 26 problemsProblemsSolutions
  • 7Tilted disk rolling inside a cylinder*not published
  • 8Heat engine between water and ice*not published
  • 9AC circuit with center-tapped inductor*not published
  • 10Achromatic two-lens eyepiece*not published
  • 11Synchronization in a relativistic cyclotron*not published
  • 12Spin-orbit fine structure of hydrogen*not published

2011

Vietnam

Day 15 problemsProblemsSolutions
  • 1Cylinder rolling inside a rolling hoop*not published
  • 2Sun as a uniform ideal-gas sphere*not published
  • 3Charge between two charged rings*not published
  • 4Radioactive gas diffusing through a shield*not published
  • 5Rotating-liquid laser and gravity measurements*not published
Day 25 problemsProblemsSolutions
  • 6Liquid meniscus under a lifted plate*not published
  • 7Runge-Lenz vector and Mercury's perihelion precession*not published
  • 8Twin paradox with heartbeat signals*not published
  • 9Photon-electron collision leaving electron at rest*not published
  • 10Friction and drag on sliding plate*not published

2010

Vietnam

Day 16 problemsProblemsSolutions
  • 1Probe launched from an orbiting station*not published
  • 2Field lines between two charges*not published
  • 3Driven coil on an elastic membrane*not published
  • 4Diffraction grating with tilted lens*not published
  • 5Phonon dispersion in a diatomic chain*not published
  • 6Zero-point molecule and relativistic kinetic energy*not published
Day 24 problemsProblemsSolutions
  • 7Hidden spring-and-ball tube masses*not published
  • 8Gas viscosity from capillary outflow*not published
  • 9Tungsten work function and electron e/m*not published
  • 10Semiconductor band gap with a monochromator*not published

2009

Vietnam

Day 16 problemsProblemsSolutions
  • 1Charged particle in a dipole field*not published
  • 2Charge in a magnetic monopole field*not published
  • 3Radiometric lift on a heated plate*not published
  • 4Light ray in a graded-index fiber*not published
  • 5Relativistic deuteron collisions*not published
  • 6Relativistic transformation of acceleration*not published
Day 24 problemsProblemsSolutions
  • 7Verifying Heisenberg uncertainty by slit diffraction*not published
  • 8Measuring a ferromagnet's Curie temperature*not published
  • 9Permeability of a ferromagnetic toroid*not published
  • 10Vacuum diode characteristics and cathode temperature*not published

2008

Vietnam

Day 16 problemsProblemsSolutions
  • 1Spring-coupled blocks with stick-slip friction*not published
  • 2Flipped gas cylinder with heavy piston*not published
  • 3Levitating square current loops*not published
  • 4Comet orbit crossing Earth's orbit*not published
  • 5Relativistic charge in uniform electric field*not published
  • 6Ioffe-Dobronravov photon experiment*not published
Day 24 problemsProblemsSolutions
  • 7Capacitive pendulum accelerometer design*not published
  • 8Characterizing a photoresistor*not published
  • 9Thin-film thickness by Young interference*not published
  • 10Planck's constant from photoresistor and lamp*not published