England · Physics · Area

Atomic physics

Atomic structure and models · Radioactive decay and evidence · Uses and nuclear energy

  • 3units
  • 9lectures planned

Scope and route

Filters show lectures with relevant core content. Mixed lectures retain clearly labelled Higher/separate extensions; those extensions are not required on other routes. Difficulty is a design rating, not a GCSE grade.

Shared
Physics and Trilogy, both tiers unless a Higher branch is named.
Separate Physics
Outside the Trilogy physics requirements.
Higher
Higher-only objectives, examples or assessments are labelled.
Ratings
Difficulty 1–4 and duration are proposed design choices; mastery means independently meeting exit criteria.

Atomic physics

Area page →

AT-U1 · Atomic structure and models

Unit page →

AT-01 · AT-U1 · Planned

Atoms, ions and isotopes

  • ScopeShared
  • Difficulty2 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Use atomic notation to count protons/neutrons/electrons; distinguish isotopes/ions; describe electron energy-level changes.

8463 §§4.4.1.1–4.4.1.2 / 8464 §§6.4.1.1–6.4.1.2

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,4.4; MS1b,3c.

Needs firstP0 standard form; PM-01

Explanation

Atomic number identifies protons; mass number counts protons plus neutrons. Isotopes differ in neutron count, while ions differ in electron count. Electromagnetic absorption can move an electron to a higher level; emission accompanies movement to a lower level in the GCSE model.

Concepts, equations and units: Atom radius about 10⁻¹⁰ m; nucleus less than 1/10,000 radius; Z protons,A nucleons; electron charge negative; radiation absorption/emission alters levels.

Prediction, demonstration and game exercise

Predict, observe, explain

Build labelled atomic diagrams with scale disclaimer; remove an electron versus change neutron count.

Planned learner game exercise

Assemble three isotope/ion identities and choose whether a transition absorbs or emits radiation.

Independent practice

Four particle-count questions, one size-ratio comparison and an energy-level explanation.

Original practice example · Shared

A neutral atom has Z = 6 and A = 14. Count protons, neutrons and electrons.

Show working and model answer

Working / reasoning

Protons = 6; neutrons = 14 − 6; neutral electrons = protons.

Answer

6 protons, 8 neutrons, 6 electrons.

Exit check and success criteria

Three counts correct, ion/isotope distinction and emission direction correct.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Positive ion gains protons; isotope means charged; electron paths are literal planetary orbits or scale-accurate rings.

Practical preparation

No RP; model and notation exercise.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-02 · AT-U1 · Planned

Evidence and the changing atomic model

  • ScopeShared
  • Difficulty3 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Use scattering evidence to explain replacement of plum-pudding model; sequence electron, nucleus, Bohr levels, proton and neutron developments.

8463 §§4.4.1.3 / 8464 §§6.4.1.3

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.1,1.2,1.6,3.6; MS2c,4a.

Needs firstAT-01

Explanation

The scattering pattern challenged a diffuse positive-charge model. Most particles passed through, supporting mostly empty space; a few strongly deflected, supporting a small dense positive nucleus. Models develop through evidence, comparison and review rather than one perfect picture.

Concepts, equations and units: Models predict observations; most alpha pass, few large deflections; nucleus tiny,dense,positive; Chadwick neutron evidence.

Prediction, demonstration and game exercise

Predict, observe, explain

Predict scattering patterns from two models then reveal an evidence histogram; explain revision and peer scrutiny.

Planned learner game exercise

Choose a model consistent with supplied trajectories and write a revision memo citing observations.

Independent practice

Interpret frequency table/histogram and produce a two-observation argument.

Original practice example · Shared

Why did rare large alpha deflections favour the nuclear model over plum pudding?

Show working and model answer

Working / reasoning

Concentrated positive charge and mass could strongly deflect a small fraction close to the nucleus; diffuse charge could not account for the pattern.

Answer

They supported a small dense positive nucleus, consistent with most alphas passing through.

Exit check and success criteria

Both key observations linked to nuclear structure and historical sequence broadly correct.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Most alpha particles hit nucleus; one diagram proves every model feature; Bohr/Chadwick experimental detail is required.

Practical preparation

No live radiation apparatus; historical-data simulation.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-U2 · Radioactive decay and evidence

Unit page →

AT-03 · AT-U2 · Planned

Radioactive decay and nuclear emissions

  • ScopeShared
  • Difficulty2 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Describe unstable-nucleus decay and activity; compare alpha, beta, gamma and neutron emissions, penetration and ionisation.

8463 §§4.4.2.1 / 8464 §§6.4.2.1

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,1.5,4.2; MS2c.

Needs firstAT-01,WA-08

Explanation

Radioactive decay is a random change of an unstable nucleus. Activity counts decays per second, whereas a detector counts only what it registers. Alpha, beta, gamma and neutron emissions differ in charge, mass and interactions; beta originates in a nuclear process, not from an ordinary electron-shell transition.

Concepts, equations and units: Activity Bq=decays/s; count rate counts/s differs due to detection; alpha helium nucleus, beta electron from nuclear process, gamma EM, neutron uncharged.

Prediction, demonstration and game exercise

Predict, observe, explain

Use stochastic model decay and shielding cards; distinguish emissions from electron-shell events.

Planned learner game exercise

Select shielding/detection for supplied evidence and classify radiation by charge, mass, range and penetration.

Independent practice

Explain decay randomness and interpret three detector/shield cases.

Original practice example · Shared

A source undergoes 300 decays per second. State activity and unit. Must a detector read 300 counts/s?

Show working and model answer

Working / reasoning

Activity is decays/s; detector efficiency, geometry and background affect measured counts.

Answer

300 Bq; no, count rate need not equal activity.

Exit check and success criteria

Alpha/beta/gamma identities and comparisons correct; neutron identified; activity/count rate distinguished.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Beta is an orbital electron ejected by warming; gamma is a massive particle; decay can be timed for one nucleus.

Practical preparation

Simulation/supplied detector data; any school source work follows specialist controls; no RP.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-04 · AT-U2 · Planned

Balancing nuclear equations

  • ScopeShared
  • Difficulty3 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Balance A and Z for alpha/beta/gamma decay; explain why gamma changes neither.

8463 §§4.4.2.2 / 8464 §§6.4.2.2

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,4.1; MS1b,3c.

Needs firstAT-03

Explanation

A nuclear equation balances nucleon number and charge/atomic-number bookkeeping. Alpha decay lowers A by four and Z by two. Beta-minus changes a neutron into a proton and emitted electron, raising the daughter’s Z by one without changing A. Gamma changes neither.

Concepts, equations and units: A/Z bookkeeping; alpha ⁴₂He, beta ⁰₋₁e; beta-minus neutron→proton in nucleus; element identity changes when Z changes.

Prediction, demonstration and game exercise

Predict, observe, explain

Demonstrate a worked alpha and beta decay; keep nucleon-number balance separate from electric charge notation.

Planned learner game exercise

Place missing daughter/emission tiles in nuclear equations and verify both balances.

Independent practice

Four equation completions plus one explanation of gamma decay.

Original practice example · Shared

A nucleus with A = 210 and Z = 84 emits an alpha particle. Give daughter A and Z.

Show working and model answer

Working / reasoning

A_daughter = 210 − 4; Z_daughter = 84 − 2.

Answer

A = 206, Z = 82.

Exit check and success criteria

Three equations correct and gamma changes neither A nor Z.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Beta emission lowers daughter Z; atomic mass number means electron count; gamma removes a proton.

Practical preparation

No RP; symbolic practice.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-05 · AT-U2 · Planned

Half-life and random decay data

  • ScopeShared + Higher net-decline calculations
  • Difficulty3 / 4 · proposed
  • Time35–40 min · estimated
  • StatusPlanned

Learning objectives

Determine half-life from data/graphs; explain aggregate predictability versus individual randomness; H calculate net decline over half-lives.

8463 §§4.4.2.3 / 8464 §§6.4.2.3

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,3.4,3.7; MS1c,3d,4a.

Needs firstAT-03; P0 fractions

Explanation

Half-life is the time for the undecayed population or activity to fall to half its value. It describes aggregate behaviour, not a schedule for one nucleus. Correct measured counts for background before estimating a source half-life. Higher calculations distinguish remaining fraction from net decline.

Concepts, equations and units: Half-life in s or labelled time; corrected count rate after background subtraction; H fractions N=N0(½)^n and decline=N0−N, integer n practice.

Prediction, demonstration and game exercise

Predict, observe, explain

Run repeat stochastic populations then plot count rate; compare large versus small samples.

Planned learner game exercise

Choose a half-life and estimate it from noisy model measurements; separate background from source counts.

Independent practice

Read two half-lives; H two remaining/declined fraction problems; estimate range from repeats.

Original practice example · Shared

A source-only count-rate graph falls from 80 to 40 counts/s in 5 minutes. Estimate half-life.

Show working and model answer

Working / reasoning

A halving interval is 5 minutes; compare another halving interval if the graph permits.

Answer

5 minutes.

Exit check and success criteria

Correct graph interval and randomness explanation; H distinguishes remaining from declined proportion.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

After two half-lives nothing remains; half-life is half the total decay time; every nucleus decays at the half-life.

Practical preparation

No RP; random-decay model/supplied counts.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-06 · AT-U2 · Planned

Contamination, irradiation and evidence quality

  • ScopeShared
  • Difficulty3 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Distinguish contamination/irradiation and their hazards; evaluate precautions and the value of peer-reviewed risk evidence.

8463 §§4.4.2.4 / 8464 §§6.4.2.4

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.5,1.6,3.7,3.8.

Needs firstAT-03,AT-05

Explanation

Irradiation exposes an object to radiation; contamination means radioactive material is on or inside it. Removing an external source ends that irradiation but does not remove deposited material. Risk conclusions need exposure data and sound methods, not just a dramatic source label.

Concepts, equations and units: Contamination radioactive material present; irradiation exposure to radiation; risk depends on radiation, dose, exposure and location.

Prediction, demonstration and game exercise

Predict, observe, explain

Compare external source removed with deposited source remaining; analyse supplied evidence without medical claims.

Planned learner game exercise

Audit lab-scenario cards for distance,time,shielding and containment choices; critique a flawed public claim.

Independent practice

Write two safety explanations and evaluate a study’s method, sample and publication status.

Original practice example · Shared

An external sealed source is removed with no material transferred to the object. Was it contaminated merely by exposure?

Show working and model answer

Working / reasoning

Exposure alone is irradiation; no radioactive material has been deposited in this scenario.

Answer

No; it was irradiated, not contaminated.

Exit check and success criteria

Both definitions correct, precautions matched to mechanism and a substantive evidence limitation identified.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Irradiation always makes an object radioactive; contamination ends when the external source is switched off.

Practical preparation

No RP; only simulated/source-based radiation safety tasks.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-U3 · Uses and nuclear energy

Unit page →

AT-07 · AT-U3 · Planned

Background radiation, uses and half-life choices

  • ScopeSeparate Physics
  • Difficulty3 / 4 · proposed
  • Time35–40 min · estimated
  • StatusPlanned

Learning objectives

Identify natural/artificial background sources; justify isotope/radiation choices for tracers and treatment using half-life and penetration.

8463 §§4.4.3.1–4.4.3.3 / No Trilogy counterpart

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.4,1.5,3.5; MS1c,2c.

Needs firstAT-05,AT-06

Explanation

Background has natural and artificial contributions. A suitable tracer or treatment isotope must match the detection/treatment purpose and exposure timescale. Activity and dose differ: dose relates to exposure risk, while Bq measures decay rate. Educational scenarios cannot determine individual medical care.

Concepts, equations and units: Background cosmic/rocks/medical/nuclear sources; dose Sv/mSv supplied; activity Bq; short/long half-life risk and usefulness; tracer versus therapy.

Prediction, demonstration and game exercise

Predict, observe, explain

Compare fictional isotope cards; distinguish diagnostic detection from treatment energy absorption.

Planned learner game exercise

Choose a tracer or treatment card using supplied half-life/penetration data and minimise exposure; choices are educational, not clinical recommendations.

Independent practice

Interpret background/dose data and justify two isotope selections with trade-offs.

Original practice example · Separate Physics

For a fictional short-duration tracer task, why might an excessively long half-life be a disadvantage?

Show working and model answer

Working / reasoning

Radioactive material can remain active long after the task, prolonging potential exposure; suitability also depends on detection and route.

Answer

It can remain radioactive longer than needed, so selection must balance usable detection time and exposure.

Exit check and success criteria

Natural/artificial sources distinguished, two evidence-based selections and risk limitation stated.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Background is entirely man-made; longest half-life always best; activity equals dose.

Practical preparation

No RP; datasets/simulation only.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-08 · AT-U3 · Planned

Fission and controlled chain reactions

  • ScopeSeparate Physics
  • Difficulty3 / 4 · proposed
  • Time30–35 min · estimated
  • StatusPlanned

Learning objectives

Explain induced fission, neutron release and chain reactions; identify control roles and energy transfers.

8463 §§4.4.4.1 / No Trilogy counterpart

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,1.4,3.6.

Needs firstAT-03,EN-11

Explanation

Fission of a heavy nucleus releases smaller nuclei, neutrons and energy. Some released neutrons can cause further fissions, giving a chain reaction. Absorbing enough neutrons controls the branching rate; the energy comes from nuclear changes rather than fuel combustion.

Concepts, equations and units: Heavy nucleus splits into two smaller nuclei plus neutrons and radiation; kinetic energy of products; control rods absorb neutrons; no mass-energy equation required.

Prediction, demonstration and game exercise

Predict, observe, explain

Show probabilistic neutron branching with controllable absorption; distinguish controlled reactor and uncontrolled chain reaction.

Planned learner game exercise

Adjust model neutron absorption to maintain a stated reaction rate and explain resulting energy ledger.

Independent practice

Label a reaction diagram and write a four-step chain/control explanation.

Original practice example · Separate Physics

Explain how absorbing neutrons changes a chain reaction.

Show working and model answer

Working / reasoning

Fewer emitted neutrons are available to induce subsequent fissions, reducing the number of new events.

Answer

It reduces subsequent fission events and can control the reaction rate.

Exit check and success criteria

Correct initiating neutron, products and subsequent-neutron chain; control explanation conserves energy.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Fission is burning; rods supply extra neutrons; every emitted neutron causes another fission.

Practical preparation

No RP; abstract model, no reactor-operation instructions.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

AT-09 · AT-U3 · Planned

Fusion and comparison with fission

  • ScopeSeparate Physics
  • Difficulty2 / 4 · proposed
  • Time25–30 min · estimated
  • StatusPlanned

Learning objectives

Explain fusion of light nuclei and energy release; compare with fission and prepare stellar link.

8463 §§4.4.4.2 / No Trilogy counterpart

DfE single-science pp.43–44 / Combined pp.35–36. Evidence checked 30 September–1 October 2026. Skills: WS1.2,3.6,4.1.

Needs firstAT-08,EN-01

Explanation

Fusion joins light nuclei into a heavier nucleus and can release energy as a small mass difference becomes energy. It is distinct from chemical burning and from fission’s splitting. Quantitative mass–energy calculations are not required in this mapped GCSE lesson.

Concepts, equations and units: Light nuclei combine into heavier nucleus; some mass becomes energy; qualitative only, no E=mc² calculation requirement.

Prediction, demonstration and game exercise

Predict, observe, explain

Contrast joining/splitting nuclear diagrams; state particle colours and sizes are symbolic.

Planned learner game exercise

Sort reaction cards and complete store/transfer maps for fusion versus fission contexts.

Independent practice

Two reaction explanations and a comparison including nuclear changes and energy source.

Original practice example · Separate Physics

Classify a process in which light nuclei combine into a heavier nucleus with energy release.

Show working and model answer

Working / reasoning

The process joins rather than splits nuclei.

Answer

Nuclear fusion.

Exit check and success criteria

Joining/splitting correctly distinguished and energy source attributed to nuclear processes rather than chemical combustion.

During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.

Misconceptions, practical links and mastery

Check these misconceptions

Fusion splits heavy nuclei; Sun burns ordinary fuel; mass conservation in ordinary phase changes forbids nuclear mass-energy release.

Practical preparation

No RP; model only.

Virtual preparation and revision only. Required hands-on activities and school records remain separate.

Proposed mastery

0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.

Full lecture page →

Sources and full programme

Sources checked 30 September–1 October 2026. Specifications govern content; textbooks supplement it. England has no single prescribed Physics course book. The full planning document includes sourced comparisons of Collins separate Physics and Trilogy books, Hodder/Hachette Physics and Oxford Physics listings, with access/approval limitations.

Download the complete Markdown programme and coverage matrix

A subsection map is proposed coverage. Clause-level educator review, item moderation, model validation and hands-on provision remain release gates. No all-board alignment or exam-board endorsement is claimed.