Numbers
AQA A-Level Physics 7408
Measurements and Their Errors
Particles and Radiation
Topic overviewConstituents of the atomStable and unstable nucleiParticles, antiparticles and photonsParticle interactionsClassification of particlesQuarks and antiquarksApplications of conservation lawsThe photoelectric effectCollisions of electrons with atomsEnergy levels and photon emissionWave-particle duality
Waves
Mechanics and Materials
Electricity
Further Mechanics and Thermal Physics
Fields and Their Consequences
Topic overviewFieldsNewton's lawGravitational field strengthGravitational potentialOrbits of planets and satellitesCoulomb's lawElectric field strengthElectric potentialCapacitanceParallel plate capacitorEnergy stored by a capacitorCapacitor charge and dischargeMagnetic flux densityMoving charges in a magnetic fieldMagnetic flux and flux linkageElectromagnetic inductionAlternating currentsTransformers
Nuclear Physics
AstrophysicsOptional topic
Topic overviewAstronomical telescope consisting of two converging lensesReflecting telescopesSingle dish radio telescopes, I-R, U-V and X-ray telescopesAdvantages of large diameter telescopesClassification by luminosityAbsolute magnitude, MClassification by temperature, black-body radiationPrinciples of the use of stellar spectral classesThe Hertzsprung-Russell (HR) diagramSupernovae, neutron stars and black holesDoppler effectHubble's lawQuasarsDetection of exoplanets
Medical PhysicsOptional topic
Topic overviewPhysics of visionDefects of vision and their correction using lensesEar as a sound detection systemSensitivity and frequency responseDefects of hearingSimple ECG machines and the normal ECG waveformUltrasound imagingFibre optics and endoscopyMagnetic resonance (MR) scannerThe physics of diagnostic X-raysImage detection and enhancementAbsorption of X-raysCT scannerImaging techniquesHalf-lifeGamma cameraUse of high-energy X-raysUse of radioactive implantsImaging comparisons
Engineering PhysicsOptional topic
Turning Points in PhysicsOptional topic
Topic overviewCathode raysThermionic emission of electronsSpecific charge of the electronPrinciple of Millikan's determination of the electronic charge, eNewton's corpuscular theory of lightSignificance of Young's double slits experimentElectromagnetic wavesThe discovery of photoelectricityWave–particle dualityElectron microscopesThe Michelson-Morley experimentEinstein's theory of special relativityTime dilationLength contractionRelativistic mass and energy
ElectronicsOptional topic
Topic overviewMOSFET (metal-oxide semiconducting field-effect transistor)Zener diodePhotodiodeHall effect sensorDifference between analogue and digital signalsLC resonance filtersThe ideal operational amplifierInverting amplifier configurationNon-inverting amplifier configurationSumming amplifier configurationReal operational amplifiersCombinational logicSequential logicAstablesPrinciples of communication systemsTransmission mediaTime-division multiplexingAmplitude (AM) and frequency modulation (FM) techniques
Particles and Radiation
- 11 subtopics
- 57 things to know
- Papers 1 and 3
What Particles and Radiation covers
Particles and radiation is examined on Papers 1 and 3. It builds the atom from its constituents, introduces antimatter and the exchange particles that carry the four interactions, classifies hadrons and leptons, and closes on the photon and wave-particle duality.
Where it is assessed
Papers 1 and 3
Core content, then practical skills and data analysis.
Check the AQA specification ↗The 11 subtopics
Each one has its own page.
- Constituents of the atomProtons, neutrons and electrons, nucleon and proton number, isotopes, and specific charge.Open →
- Stable and unstable nucleiThe strong nuclear force and why some nuclei are unstable, alpha and beta-minus decay and their equations, why the antineutrino had to be proposed to explain the spread of beta energies, and investigating the range of radiation.Open →
- Particles, antiparticles and photonsAntiparticles, rest energy in MeV, the photon model, and annihilation and pair production.Open →
- Particle interactionsThe four fundamental interactions and their exchange particles, and Feynman diagrams for beta decay and electron capture.Open →
- Classification of particlesHadrons and leptons, baryons and mesons, and the baryon, lepton and strangeness numbers.Open →
- Quarks and antiquarksThe up, down and strange quarks and their properties, and the quark composition of baryons and mesons.Open →
- Applications of conservation lawsChecking charge, baryon number, lepton number and strangeness to decide whether an interaction can happen.Open →
- The photoelectric effectThreshold frequency, the work function, the photoelectric equation and stopping potential.Open →
- Collisions of electrons with atomsExcitation and ionisation, the electron volt, and how a fluorescent tube works.Open →
- Energy levels and photon emissionDiscrete energy levels, emission and absorption line spectra, and the diffraction grating.Open →
- Wave-particle dualityThe de Broglie wavelength, electron diffraction, and how scientific ideas are tested and accepted.Open →
What you need to know
Answer each one before you reveal it.
Your recallNot started
Numbers
What charge does each of the three sub-atomic particles carry?
Numbers
What is specific charge, and what values does an electron and a proton take?
Process
How is the specific charge of an ion or a nucleus calculated?
Key term
In nuclide notation ᴬ_Z X, what does the subscript Z represent?
Key term
In nuclide notation ᴬ_Z X, what does X represent?
Numbers
Why must the antineutrino be included in a beta-minus decay equation?
Numbers
What is a femtometre, and what evidence led to proposing the neutrino?
Numbers
What happens to an unstable nucleus during alpha decay?
Process
What happens to the mass number during beta-minus decay?
Process
Name three methods that can be used to demonstrate the range of alpha particles in air
Numbers
How do the mass and charge of an antiparticle compare with its corresponding particle?
Key term
In what unit is rest energy given, and why is the antineutron uncharged?
Numbers
How is a photon's energy related to the wave it belongs to, and what do the symbols mean?
Numbers
How is photon energy expressed using wavelength, when is that form used instead of E = hf, and what is the Planck constant?
Key term
Why must pair production occur in the vicinity of a nucleus?
Key term
How many gamma photons are produced when a slow electron annihilates with a slow positron?
Key term
What are the four fundamental interactions, and which acts between masses?
Key term
How are forces between elementary particles explained, what do exchange particles transfer, and what carries the electromagnetic force?
Key term
What does the W⁻ boson decay into, and what happens in beta-plus decay?
Process
What does the proton absorb in electron capture, and which boson mediates it?
Key term
In an electron-proton collision via the weak interaction, which particle emits the W⁻ boson?
Key term
What physical quantity do exchange particles transfer between interacting particles?
Key term
What defines a hadron, and how are hadrons divided?
Numbers
What is baryon number, and what value does a baryon take?
Numbers
Why do mesons have a baryon number of zero?
Process
What role does the pion play, and what do unstable baryons and kaons decay into?
Key term
Which two neutrinos are required, and how are neutrinos classified?
Numbers
What is the baryon number of a baryon?
Key term
Which letter denotes strangeness in particle physics?
Key term
What high-energy particles can be found in cosmic ray showers?
Process
How does a quark's charge compare with its opposite, and what values does an up quark take?
Key term
What is the quark composition of a baryon and of an antibaryon?
Key term
What are the quark compositions of the antiproton, the neutron and the antineutron?
Numbers
What is the charge of the π⁻ meson, and what is its quark composition?
Numbers
What is the quark structure of the K⁺ meson, and what strangeness does it carry?
Key term
Which meson is made from a strange quark and an anti-up quark?
Numbers
What is the total baryon number of all the quarks in a baryon?
Numbers
How do you verify that baryon number and charge are conserved in a proposed interaction?
Numbers
How do you check lepton number, strangeness and baryon number in an interaction?
Key term
A kaon decays into pions. Explain why this decay must occur via the weak interaction
Key term
In which type of interaction is strangeness conserved?
Numbers
What do the terms in hf = φ + Eₖ mean, and what is stopping potential?
Key term
What is the work function, and why does light below the threshold emit nothing?
Process
How do intensity and frequency each affect photoelectric emission?
Key term
Describe how the photoelectric effect can be demonstrated using a zinc plate and an electroscope
Numbers
How is an energy in electron volts converted into SI units?
Numbers
What is the electron volt, and how does a fluorescent tube produce visible light?
Key term
What condition must the kinetic energy of a colliding electron satisfy for excitation of an atomic electron to occur?
Numbers
In what units are energy levels given, and how is photon frequency found from them?
Key term
How is an absorption line spectrum produced, and how does it look beside an emission spectrum?
Key term
How is a diffraction grating used to observe line spectra, and what is the ground state?
Key term
What are excited states in an atom?
Process
What happens to the wavelength of an emitted photon as the energy difference between levels increases?
Numbers
What is the de Broglie wavelength, and how is the equation written using momentum?
Evaluation
What is required for a change in scientific understanding to be accepted?
Key term
How has scientific understanding of the nature of matter developed?
Take Particles and Radiation further
The same content, four other ways.
Commonly confused
Pairs that lose marks when they are blurred together.
Hadron vs Lepton
Hadron: particle experiencing the strong interaction. Lepton: fundamental particle not experiencing the strong interaction.
Baryon vs Meson
Baryon: hadron made from three quarks. Meson: hadron made from a quark and antiquark.
Antiparticle vs Isotope
Antiparticle: counterpart with equal mass and opposite quantum numbers. Isotope: nucleus with fixed proton count and differing neutron count.
Questions from this topic
Each one with the model answer underneath.
- 1
In the simple atomic model, what particles are found inside the nucleus?
Model answer
Protons and neutrons.
- 2
Where are electrons located in the simple model of the atom?
Model answer
Electrons orbit the nucleus.
- 3
What is the charge of a proton in coulombs?
Model answer
+1.60 × 10⁻¹⁹ C.
- 4
What is the charge of a neutron?
Model answer
Zero (the neutron has no charge).
- 5
State the charge of an electron in coulombs.
Model answer
−1.60 × 10⁻¹⁹ C.
- 6
What is the mass of a proton in kilograms?
Model answer
1.67 × 10⁻²⁷ kg.
What is inside Levo
Six ways to work the same material.
Particles and Radiation revision questions
- What does Particles and Radiation cover in AQA A-Level Physics?
- 11 subtopics: constituents of the atom, stable and unstable nuclei, particles, antiparticles and photons, particle interactions, classification of particles, quarks and antiquarks, applications of conservation laws, the photoelectric effect, collisions of electrons with atoms, energy levels and photon emission and wave-particle duality. Each one has its own page with questions and model answers.
- How is Particles and Radiation organised?
- By the AQA 7408 specification, subtopic by subtopic, so it matches the order you are taught it in.
Every question in Particles and Radiation, on a schedule.
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