IB Physics Revision

Atomic, Nuclear & Quantum

Atomic and nuclear structure, radioactivity, and quantum and particle physics.

Atomic, Nuclear & Quantum is a core part of IB Physics. Revise the key concepts and common mistakes below, then lock them in with the free games.

Key concepts

Alpha particleHelium nucleus (²He²⁺)
Rutherford scatteringDense + nucleus revealed
Energy levelsDiscrete states for electrons
hf = E₂ - E₁Photon energy of transition
Emission spectrumDiscrete lines from de-excitation
Absorption spectrumDark lines on continuous bg
QuarkFundamental; u/d/c/s/t/b
LeptonFundamental; e, μ, τ + neutrinos
HadronMade of quarks (baryon or meson)
Baryon3 quarks (proton uud, neutron udd)
MesonQuark + antiquark (e.g. pion ud̄)
Gauge bosonForce carrier (γ, W, Z, g, H)
Alpha α⁴He nucleus, 2p + 2n
Beta β⁻n → p + e⁻ + ν̄

Common mistakes to avoid

Questions where students often pick the tempting wrong answer — make sure you know the right one:

Which radiation is most ionising?✗ Gamma, because it is most penetrating.   ✓ Alpha — most ionising but least penetrating (stopped by paper).
Can heating a source change its half-life?✗ Yes, heating speeds up decay and shortens half-life.   ✓ No — half-life is fixed and unaffected by temperature or pressure.

Practise Atomic, Nuclear & Quantum — free games

Test yourself with these quick revision games for this topic:

▶ Two Truths, One Lie▶ Reveal Race▶ Connections Grid▶ Falling Words▶ Word Web

See all 17 games in the Subjects Arcade →

More IB Physics topics

MechanicsThermal PhysicsWavesElectricity & MagnetismFields & GravitationEnergy ProductionAstrophysics

← All revision guides

Want to revise every topic this smart?

The Velvet Method teaches you to use AI to revise any subject — £25, lifetime access.

Explore the Course →