# Topic Questions: 136 understand the mechanism of nuclear fusion and the need for very high densities of matter and very high temperatures to bring about and maintain nuclear fusion — WPH15 Nuclear Decay

> 12 WPH15 Nuclear Decay topic questions (40 marks) on 136 understand the mechanism of nuclear fusion… — 11 papers, 2020–2026. Open the exact question in the…

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Edexcel IAL · Physics · WPH15 · Nuclear Decay

12 WPH15 Nuclear Decay topic questions are tagged to this syllabus point across 11 papers (2020–2026). Only the parts whose knowledge graph matches this syllabus statement are counted, and the table shows which parts of each question are involved.

- 12 topic questions
- 11 papers
- 40 tagged marks
- 6.7% of topic questions
- 8.8% of topic marks
- 2020–2026
- Syllabus 2018–current
- [All WPH15 Nuclear Decay topic questions](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/)
- [All paper codes](https://www.examsci.com/topics/)

Core finding

**This Nuclear Decay syllabus point appears in 11 WPH15 papers across 2020–2026, contributing 12 topic questions and 40 marks.** The most recent appearance is WPH15/01 January 2026. That equals 6.7% of the 178 topic questions and 8.8% of the 455 marks tagged to Nuclear Decay. Only parts tagged to this subtopic are counted, so a four-part question can contribute one item and one part's marks. The table lists every matching question, its tagged parts and marks, with a link back to the paper page. Sessions are newest first, so the statement can be traced back through the full paper history.

## Topic questions by session

Newest sessions first. Parts and marks count only the parts tagged to this subtopic; “x of y parts” shows how much of the question is tagged elsewhere. Select the paper cell to open the matching question on the paper page, or use **Go to Practice Hub** to answer that exact question in the Interactive Practice Hub.

| Paper | Question | Type | Parts | Marks | Difficulty | Practice |
| --- | --- | --- | --- | --- | --- | --- |
| [**WPH15/01** January 2026 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2026-january-wph15-01/#q-14) | **Q14** Nuclear Fission, Fusion and Stellar Conditions - Edexcel IAL Physics Jan 2026 Q14 | FRQ | 1 of 2 parts ((b)) | 6 of 9 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=33df4133-3f97-49c4-8770-848b232eb7b1&question_id=cf370bca-5748-4a88-85ac-f7eec368af59&source_detail=WPH15%2F01+January+2026) |
| [**WPH15/01** October 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2024-october-wph15-01/#q-20) | **Q20** Edexcel IAL Physics Unit 5 Oct 2024 Q20 | FRQ | 1 of 3 parts ((b)) | 6 of 13 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3e10632c-bdcc-44a6-afc4-5f4f7a30978e&question_id=06074343-0802-4b02-81cf-b8e987721889&source_detail=WPH15%2F01+October+2024) |
| [**WPH15/01** January 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2024-january-wph15-01/#q-21) | **Q21** Nuclear Decay - Edexcel IAL Physics Jan 2024 Q21 | FRQ | 1 of 3 parts ((a)) | 6 of 12 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=81ae8d95-9845-43d2-85aa-56edeba0f606&question_id=59dd0cab-8418-4400-a129-43839c1678aa&source_detail=WPH15%2F01+January+2024) |
| [**WPH15/01** October 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2023-october-wph15-01/#q-1) | **Q1** Stellar Fusion Conditions - Edexcel IAL Physics Oct 2023 Q1 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=c6d9493b-ab37-4b2a-967c-30f17fd52e71&question_id=0a90d3d9-7b40-4ef8-a64e-bee4a54c1a82&source_detail=WPH15%2F01+October+2023) |
| [**WPH15/01** June 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2023-june-wph15-01/#q-17) | **Q17** Edexcel IAL Physics Unit 5 June 2023 Q17 | FRQ | 1 of 3 parts ((b)) | 4 of 9 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=25ca8d3d-f529-419a-8ab4-22f4c43251b4&question_id=3b2269ef-8bd0-4f06-9652-28be12473188&source_detail=WPH15%2F01+June+2023) |
| [**WPH15/01** October 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2022-october-wph15-01/#q-1) | **Q1** Nuclear Processes - Edexcel IAL Physics Oct 2022 Q1 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=11a7a1e1-92c0-4c27-923f-84fabaf236e5&question_id=d4981775-acdc-4d05-9273-450416b17979&source_detail=WPH15%2F01+October+2022) |
| [**WPH15/01** June 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2022-june-wph15-01/#q-5) | **Q5** Nuclear Fusion Conditions in Stellar Core - Edexcel IAL Physics Jun 2022 Q5 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=9a093fb4-7c1b-4987-9e36-33b3e20c2b25&question_id=63d6988b-1890-416e-8fb5-abeb5d66ff51&source_detail=WPH15%2F01+June+2022) |
| [**WPH15/02** January 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2022-january-wph15-02/#q-1) | **Q1** Stellar Fusion Requirements - Edexcel IAL Physics Jan 2022 Q1 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=23304130-a638-4c40-b130-1921931842df&question_id=e2d64f34-6277-4b71-a1b9-114007797466&source_detail=WPH15%2F02+January+2022) |
| [**WPH15/02** January 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2022-january-wph15-02/#q-18) | **Q18** Stellar Evolution of Delta Pavonis - Edexcel IAL Physics Jan 2022 Q18 | FRQ | 1 of 3 parts ((b)) | 3 of 9 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=23304130-a638-4c40-b130-1921931842df&question_id=cdf8a264-c1ef-4d31-acc0-732e3d86b90b&source_detail=WPH15%2F02+January+2022) |
| [**WPH15/01** October 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2021-october-wph15-01/#q-15) | **Q15** Stellar Nuclear Fusion Conditions - Edexcel IAL Physics Oct 2021 Unit 5 Q15 | FRQ | 1 part | 6 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=85f00adf-61bf-4290-b7e1-556838a91d6f&question_id=50678fab-b9dd-433e-88c4-dc18261f6f82&source_detail=WPH15%2F01+October+2021) |
| [**WPH15/01** June 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2021-june-wph15-01/#q-4) | **Q4** Conditions for Solar Fusion - Edexcel IAL Physics Jun 2021 Q4 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=ab093dfb-339d-4a8a-9997-6d539dfdc6b8&question_id=826b3512-9d24-42a7-baa2-91f43fb30733&source_detail=WPH15%2F01+June+2021) |
| [**WPH15/01** October 2020 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-5-wph15/2020-october-wph15-01/#q-13) | **Q13** Difficulties of Nuclear Fusion - Edexcel IAL Physics Oct 2020 Q13 | FRQ | 1 part | 4 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=1a3931f7-4a72-41eb-af5a-0d315b2148a6&question_id=8e3a3e75-d785-40aa-91a2-65feb00222a6&source_detail=WPH15%2F01+October+2020) |

## Related topic questions in Nuclear Decay

- [133 understand the concept of nuclear binding energy and be able to use the equation $\Delta E=c^{2}\Delta m$ in calculations of nuclear mass (including mass deficit) and energy](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/133-understand-the-concept-of-nuclear-binding-energy-and-be-able-to-use-the-equation/) — 38 question items · 20 papers — 122 marks · 2020–2026
- [134 use the atomic mass unit (u) to express small masses and convert between this and SI units](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/134-use-the-atomic-mass-unit-u-to-express-small-masses-and-convert-between-this-and/) — 18 question items · 16 papers — 77 marks · 2020–2026
- [135 understand the processes of nuclear fusion and fission with reference to the binding energy per nucleon curve](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/135-understand-the-processes-of-nuclear-fusion-and-fission-with-reference-to-the/) — 23 question items · 15 papers — 42 marks · 2020–2026
- [137 understand that there is background radiation and how to take appropriate account of it in calculations](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/137-understand-that-there-is-background-radiation-and-how-to-take-appropriate-account/) — 10 question items · 10 papers — 13 marks · 2020–2026
- [138 understand the relationships between the nature, penetration, ionising ability and range in different materials of nuclear radiations (alpha, beta and gamma)](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/138-understand-the-relationships-between-the-nature-penetration-ionising-ability-and/) — 23 question items · 18 papers — 53 marks · 2020–2026
- [139 be able to write and interpret nuclear equations given the relevant particle symbols](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-5-wph15/nuclear-decay/139-be-able-to-write-and-interpret-nuclear-equations-given-the-relevant-particle/) — 26 question items · 20 papers — 54 marks · 2020–2026

## Topic question rules and edge cases

**How many topic questions cover this syllabus point?**

12 question stems cover this subtopic across 11 papers, but only 12 tagged parts and 40 marks belong to it. Other parts of the same questions are assessed under different statements and are excluded from this page.

**Which papers include this subtopic?**

The table lists every matching session from 2020–2026. Each row links to the question anchor on the paper page, where the full paper context and practice entry point are available.

**Why can one question appear under several subtopics?**

The parts of one question can assess different syllabus statements. Each part is counted under its own subtopics, so the same question stem can appear on several subtopic pages while each page lists only the parts and marks tagged to that statement.

**Can I practise these questions with AI marking?**

Yes. Open a paper from the table and use the Interactive Practice Hub entry point. The page itself is static HTML so search engines and retrieval agents can read the full question list without executing JavaScript.

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