A 0.5 kg mass hangs on a spring of stiffness 200 N/m. What is the period of its oscillation?ETS, GRE Physics Test content: Classical Mechanics (20%), oscillatory motion. Wikipedia, "Simple harmonic motion".
A 2 kg block sliding at 3 m/s on a level floor stops after 1.5 m. Taking g = 10 m/s², what is the coefficient of kinetic friction?ETS, GRE Physics Test content: Classical Mechanics (20%), work and energy. Wikipedia, "Friction".
A 2 kg cart moving at 3 m/s hits a 1 kg cart at rest and sticks to it. How much kinetic energy is lost?ETS, GRE Physics Test content: Classical Mechanics (20%), dynamics of systems of particles. Wikipedia, "Inelastic collision".
A ball is thrown straight up at 20 m/s. Taking g = 10 m/s² and ignoring air resistance, how high does it rise?ETS, GRE Physics Test content: Classical Mechanics (20%), kinematics. Wikipedia, "Equations of motion".
A block slides down a frictionless incline tilted 30° from the horizontal. With g = 9.8 m/s², what is its acceleration?ETS, GRE Physics Test content: Classical Mechanics (20%), Newton's laws. Wikipedia, "Inclined plane".
Show all 70 questions (65 more)
Classical mechanics, continued
A generalized coordinate does not appear in a system's Lagrangian, though its velocity does. What follows?ETS, GRE Physics Test content: Classical Mechanics (20%), Lagrangian and Hamiltonian formalism. Wikipedia, "Lagrangian mechanics".
A projectile leaves level ground at 20 m/s, 45° above the horizontal. Taking g = 10 m/s² and ignoring air resistance, how far away does it land?ETS, GRE Physics Test content: Classical Mechanics (20%), kinematics. Wikipedia, "Projectile motion".
A satellite is moved to a circular orbit of twice the radius. By what factor does its orbital period change?ETS, GRE Physics Test content: Classical Mechanics (20%), central forces and celestial mechanics. Wikipedia, "Kepler's laws of planetary motion".
A spinning skater pulls in her arms and halves her moment of inertia. No outside torque acts. What happens to her rotational kinetic energy?ETS, GRE Physics Test content: Classical Mechanics (20%), rotational motion, dynamics of systems of particles. Wikipedia, "Angular momentum".
A uniform solid disk rolls without slipping from rest down a ramp, dropping 0.6 m in height. Taking g = 10 m/s², what is the speed of its center at the bottom?ETS, GRE Physics Test content: Classical Mechanics (20%), rotational motion about a fixed axis. Wikipedia, "List of moments of inertia".
At a given distance from a planet, what is the ratio of the escape speed to the speed of a circular orbit?ETS, GRE Physics Test content: Classical Mechanics (20%), central forces and celestial mechanics. Wikipedia, "Escape velocity".
The length of a simple pendulum is made four times as long. For small swings, what happens to its period?ETS, GRE Physics Test content: Classical Mechanics (20%), oscillatory motion. Wikipedia, "Pendulum".
Masses of 3 kg and 2 kg hang from a light string over a frictionless, massless pulley. With g = 9.8 m/s², what is the magnitude of their acceleration?ETS, GRE Physics Test content: Classical Mechanics (20%), Newton's laws. Wikipedia, "Atwood machine".
Water flows at 2 m/s through a full pipe. The pipe narrows to half its radius. How fast does the water flow in the narrow part?ETS, GRE Physics Test content: Classical Mechanics (20%), elementary topics in fluid dynamics. Wikipedia, "Continuity equation".
Electromagnetism 13
A 5 μF capacitor discharges through a 2 kΩ resistor. What is the time constant?ETS, GRE Physics Test content: Electromagnetism (18%), currents and DC circuits. Wikipedia, "RC time constant".
A 12 V battery drives a 2 Ω resistor in series with a parallel pair of 6 Ω and 3 Ω resistors. What current leaves the battery?ETS, GRE Physics Test content: Electromagnetism (18%), currents and DC circuits. Wikipedia, "Series and parallel circuits".
A charged parallel-plate capacitor is disconnected from its battery. A slab with dielectric constant 3 then fills the gap. What happens to the stored energy?ETS, GRE Physics Test content: Electromagnetism (18%), electric fields in matter. Wikipedia, "Capacitor".
A circuit has a 10 mH inductor and a 1 μF capacitor in series. Near which frequency does it resonate?ETS, GRE Physics Test content: Electromagnetism (18%), AC circuits. Wikipedia, "LC circuit".
A coil of 100 turns, each of area 0.02 m², lies at right angles to a magnetic field that rises steadily by 0.5 T each second. What emf is induced?ETS, GRE Physics Test content: Electromagnetism (18%), induction. Wikipedia, "Faraday's law of induction".
A long straight wire carries 10 A. With μ₀ = 4π × 10⁻⁷ T·m/A, how strong is the magnetic field 2 cm from the wire?ETS, GRE Physics Test content: Electromagnetism (18%), magnetic fields in free space. Wikipedia, "Ampère's circuital law".
A proton (mass 1.67 × 10⁻²⁷ kg, charge 1.60 × 10⁻¹⁹ C) moves at 2.0 × 10⁶ m/s at right angles to a 0.50 T magnetic field. What is the radius of its path?ETS, GRE Physics Test content: Electromagnetism (18%), Lorentz force. Wikipedia, "Gyroradius".
A slow charged particle circles in a uniform magnetic field. If its speed doubles, still far below the speed of light, what happens to the time for one orbit?ETS, GRE Physics Test content: Electromagnetism (18%), Lorentz force. Wikipedia, "Cyclotron".
A solid insulating sphere of radius R carries charge spread evenly through its volume. Compared with the field at its surface, how strong is the electric field at R/2 from the center?ETS, GRE Physics Test content: Electromagnetism (18%), electrostatics. Wikipedia, "Gauss's law".
The north pole of a bar magnet is pushed toward a closed conducting ring. Which way does the induced current act?ETS, GRE Physics Test content: Electromagnetism (18%), induction. Wikipedia, "Lenz's law".
Two point charges repel with force F. One charge is tripled and the distance between them is doubled. What is the new force?ETS, GRE Physics Test content: Electromagnetism (18%), electrostatics. Wikipedia, "Coulomb's law".
Which of Maxwell's equations states that isolated magnetic poles do not exist?ETS, GRE Physics Test content: Electromagnetism (18%), Maxwell's equations and their applications. Wikipedia, "Gauss's law for magnetism".
Which term did Maxwell add to Ampère's law, making electromagnetic waves possible?ETS, GRE Physics Test content: Electromagnetism (18%), electromagnetic waves. Wikipedia, "Displacement current".
Optics and wave phenomena 6
A siren sounding 900 Hz moves toward a listener at 34 m/s. Sound travels at 340 m/s and the air is still. What frequency does the listener hear?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), Doppler effect. Wikipedia, "Doppler effect".
A string 0.6 m long is fixed at both ends, and waves travel along it at 240 m/s. What is its fundamental frequency?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), wave properties, superposition. Wikipedia, "Standing wave".
An object stands 30 cm in front of a thin converging lens of focal length 10 cm. Where is the image?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), geometrical optics. Wikipedia, "Lens".
Light of wavelength 500 nm passes through two slits 0.2 mm apart and falls on a screen 2 m away. How far apart are neighboring bright fringes?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), interference. Wikipedia, "Double-slit experiment".
Light passes through a single slit whose width is twice the wavelength. At what angle from the center is the first dark band?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), diffraction. Wikipedia, "Diffraction".
Unpolarized light of intensity I₀ passes through two ideal polarizers whose axes are 60° apart. What intensity comes out?ETS, GRE Physics Test content: Optics and Wave Phenomena (8%), polarization. Wikipedia, "Polarizer".
Thermodynamics and statistical mechanics 7
600 J of heat flows from a reservoir at 600 K into a reservoir at 300 K. What is the total change in entropy?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), the laws of thermodynamics. Wikipedia, "Second law of thermodynamics".
A gas takes in 500 J of heat and does 200 J of work on its surroundings. How does its internal energy change?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), the laws of thermodynamics. Wikipedia, "First law of thermodynamics".
A system in thermal equilibrium has two states, the upper one an energy ε above the lower. At the temperature where kT = ε, what is the ratio of the upper population to the lower?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), ensembles, statistical concepts. Wikipedia, "Boltzmann distribution".
The absolute temperature of an ideal gas is made four times as great. By what factor does the root-mean-square speed of its molecules change?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), kinetic theory. Wikipedia, "Root mean square speed".
An ideal reversible engine runs between reservoirs at 600 K and 300 K. What is its efficiency?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), thermodynamic processes. Wikipedia, "Carnot heat engine".
One mole of ideal gas doubles its volume at a constant 300 K. With R = 8.31 J/(mol·K), how much work does the gas do?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), thermodynamic processes, ideal gases. Wikipedia, "Isothermal process".
What is the ratio of specific heats, C_p / C_v, for an ideal monatomic gas?ETS, GRE Physics Test content: Thermodynamics and Statistical Mechanics (10%), ideal gases, kinetic theory. Wikipedia, "Heat capacity ratio".
Quantum mechanics 9
A particle sits in a one-dimensional infinite square well. How many times its ground-state energy is the energy of the n = 3 level?ETS, GRE Physics Test content: Quantum Mechanics (13%), solutions of the Schrödinger equation: square wells. Wikipedia, "Particle in a box".
A quantum harmonic oscillator has angular frequency ω. What is the energy of its second excited state?ETS, GRE Physics Test content: Quantum Mechanics (13%), solutions of the Schrödinger equation: harmonic oscillators. Wikipedia, "Quantum harmonic oscillator".
A small perturbation H′ is added to a system in the nondegenerate state |n⟩. What is the first-order shift in its energy?ETS, GRE Physics Test content: Quantum Mechanics (13%), elementary perturbation theory. Wikipedia, "Perturbation theory (quantum mechanics)".
A spin-½ particle is in the normalized state (3/5)|up⟩ + (4/5)|down⟩ along z. What is the probability that a measurement of S_z gives +ħ/2?ETS, GRE Physics Test content: Quantum Mechanics (13%), spin, fundamental concepts. Wikipedia, "Born rule".
An electron (mass 9.11 × 10⁻³¹ kg) has a kinetic energy of 150 eV. With h = 6.63 × 10⁻³⁴ J·s and 1 eV = 1.60 × 10⁻¹⁹ J, what is its de Broglie wavelength?ETS, GRE Physics Test content: Quantum Mechanics (13%), fundamental concepts. Wikipedia, "Matter wave".
An electron is in a state with orbital quantum number l = 2. What is the magnitude of its orbital angular momentum?ETS, GRE Physics Test content: Quantum Mechanics (13%), angular momentum. Wikipedia, "Azimuthal quantum number".
Hydrogen has a ground-state energy of −13.6 eV. What is the energy of the n = 2 level of the He⁺ ion, which has one electron and nuclear charge 2?ETS, GRE Physics Test content: Quantum Mechanics (13%), solutions of the Schrödinger equation: hydrogenic atoms. Wikipedia, "Hydrogen-like atom".
Two identical fermions are exchanged. What must happen to their total wave function?ETS, GRE Physics Test content: Quantum Mechanics (13%), wave function symmetry. Wikipedia, "Identical particles".
What is the commutator [x, p] of the position and momentum operators along the same axis?ETS, GRE Physics Test content: Quantum Mechanics (13%), fundamental concepts. Wikipedia, "Canonical commutation relation".
Atomic physics 7
A star's surface radiates like a black body at 5,800 K. With Wien's constant b = 2.90 × 10⁻³ m·K, at what wavelength is its spectrum brightest?ETS, GRE Physics Test content: Atomic Physics (10%), black-body radiation. Wikipedia, "Wien's displacement law".
The absolute temperature of a black body is doubled. By what factor does the power it radiates change?ETS, GRE Physics Test content: Atomic Physics (10%), black-body radiation. Wikipedia, "Stefan–Boltzmann law".
An x-ray tube runs at 30 kV. Using hc = 1,240 eV·nm, what is the shortest wavelength in its spectrum?ETS, GRE Physics Test content: Atomic Physics (10%), x-rays. Wikipedia, "Duane–Hunt law".
In an electric dipole transition of a one-electron atom, by how much must the orbital quantum number l change?ETS, GRE Physics Test content: Atomic Physics (10%), selection rules, atomic spectra. Wikipedia, "Selection rule".
In the Bohr model, the hydrogen levels are E_n = −13.6 eV / n². What photon energy is given off when the electron drops from n = 3 to n = 2?ETS, GRE Physics Test content: Atomic Physics (10%), Bohr model, energy quantization. Wikipedia, "Bohr model".
Photons of energy 3.1 eV strike a metal whose work function is 2.0 eV. What is the greatest kinetic energy of the electrons that come out?ETS, GRE Physics Test content: Atomic Physics (10%), properties of electrons. Wikipedia, "Photoelectric effect".
Spectral lines of an atom split into several components when the atom sits in a steady magnetic field. What is this called?ETS, GRE Physics Test content: Atomic Physics (10%), atoms in electric and magnetic fields. Wikipedia, "Zeeman effect".
Special relativity 4
A muon lives 2.2 μs in its own rest frame. It moves at 0.8c through a laboratory. How long does it live as measured in the laboratory?ETS, GRE Physics Test content: Special Relativity (6%), time dilation. Wikipedia, "Time dilation".
A particle has rest energy 3 MeV and momentum 4 MeV/c. What is its total energy?ETS, GRE Physics Test content: Special Relativity (6%), energy and momentum. Wikipedia, "Energy–momentum relation".
A ship 100 m long in its own rest frame passes an observer at 0.6c. How long does the observer measure it to be?ETS, GRE Physics Test content: Special Relativity (6%), length contraction. Wikipedia, "Length contraction".
A ship moves at 0.5c past Earth and fires a probe forward at 0.5c relative to the ship. How fast is the probe relative to Earth?ETS, GRE Physics Test content: Special Relativity (6%), velocity addition. Wikipedia, "Velocity-addition formula".
Laboratory methods 4
A detector counts random decays. About how many counts must it collect for the statistical uncertainty to be 1% of the count?ETS, GRE Physics Test content: Laboratory Methods (6%), counting statistics, radiation detection. Wikipedia, "Poisson distribution".
A length is measured 25 times, and the readings scatter with a standard deviation of 0.5 mm. What is the standard error of their mean?ETS, GRE Physics Test content: Laboratory Methods (6%), fundamental applications of probability and statistics. Wikipedia, "Standard error".
A low-pass filter is built from a 1.6 kΩ resistor and a 0.1 μF capacitor. Near what frequency is its cutoff?ETS, GRE Physics Test content: Laboratory Methods (6%), electronics. Wikipedia, "Low-pass filter".
Two independent measurements are A = 10.0 ± 0.3 and B = 5.0 ± 0.4. What is the uncertainty of their sum?ETS, GRE Physics Test content: Laboratory Methods (6%), data and error analysis. Wikipedia, "Propagation of uncertainty".
Specialized topics 6
A metal is cooled below its superconducting transition in a weak magnetic field. What happens to the field inside it?ETS, GRE Physics Test content: Specialized Topics (9%), condensed matter: superconductors. Wikipedia, "Meissner effect".
A nucleus undergoes beta-minus decay. How do its atomic number Z and mass number A change?ETS, GRE Physics Test content: Specialized Topics (9%), nuclear and particle physics: radioactive decay. Wikipedia, "Beta decay".
A sample of a radioactive isotope has a half-life of 5 days. What fraction of the original nuclei is left after 15 days?ETS, GRE Physics Test content: Specialized Topics (9%), nuclear and particle physics: radioactive decay. Wikipedia, "Half-life".
Taking the Hubble constant as 70 km/s per megaparsec, how fast is a galaxy 100 megaparsecs away receding?ETS, GRE Physics Test content: Specialized Topics (9%), miscellaneous: astrophysics. Wikipedia, "Hubble's law".
Which of these particles is a lepton?ETS, GRE Physics Test content: Specialized Topics (9%), nuclear and particle physics: fundamental properties of elementary particles. Wikipedia, "Lepton".
X-rays of wavelength 0.20 nm reflect from crystal planes 0.20 nm apart. At what angle to the planes is the first-order Bragg peak?ETS, GRE Physics Test content: Specialized Topics (9%), condensed matter: x-ray diffraction, crystal structure. Wikipedia, "Bragg's law".
How this list was compiled: Our own questions, written to the content description ETS publishes for the GRE Physics Test (https://www.ets.org/gre/test-takers/subject-tests/about/content-structure.html, read 2026-10-09) and to the topic list on pages 3 and 4 of its GRE Physics Test Practice Book (https://www.ets.org/pdfs/gre/practice-book-physics.pdf): Classical Mechanics 20%, Electromagnetism 18%, Optics and Wave Phenomena 8%, Thermodynamics and Statistical Mechanics 10%, Quantum Mechanics 13%, Atomic Physics 10%, Special Relativity 6%, Laboratory Methods 6%, Specialized Topics 9%. The bank holds 14, 13, 6, 7, 9, 7, 4, 4 and 6 questions. Each law was read on 2026-10-09 in the Wikipedia article named under its question, and every numerical answer was worked out a second time from the numbers the question prints. Licence: Questions, choices and explanations are original work of this site.
How it works
This free GRE Physics practice test has 70 questions of our own, spread over the nine content areas in ETS's proportions. It is unofficial and is not affiliated with, endorsed by or sponsored by ETS.
Read the full guide
Nine content areas
ETS's content description, read October 9, 2026: classical mechanics 20%, electromagnetism 18%, optics and wave phenomena 8%, thermodynamics and statistical mechanics 10%, quantum mechanics 13%, atomic physics 10%, special relativity 6%, laboratory methods 6%, specialized topics 9%. This bank holds 14, 13, 6, 7, 9, 7, 4, 4 and 6 questions.
Full length
The real test has about 70 five-choice questions in 2 hours. Exam mode gives all 70 of ours on the same clock; ours have four choices.
What to review
ETS says most questions can be answered from the first three years of undergraduate physics, and that a general review of college courses is probably the best preparation.
Nothing is taken off for a wrong answer, so leave no question blank.
The real test gives a table of physical constants and SI conversion factors. Learn the laws, not the digits.
Every question counts the same. Pass over a slow one and come back to it.
Questions and answers
How many questions are on the GRE Physics test?
About 70, each with five choices, in a total testing time of 2 hours. ETS gives the test on computer, and no section is timed separately.
Is this GRE Physics subject test practice official?
No. All 70 questions were written for this page from ETS's published content areas, and each numerical answer is worked from the numbers in the question. None is taken or reworded from a real test or from ETS's practice book.
Are there physics GRE study guides from ETS?
ETS publishes a free GRE Physics Test Practice Book. It lists the topics under each content area, gives test-taking strategies and explains scoring, and it holds one full-length practice test with a scoring worksheet.
How is the GRE Physics test scored?
ETS reports a total scaled score from 200 to 990 in ten-point steps, and three percent-correct scores: classical mechanics, electromagnetism, and quantum mechanics with atomic physics.