# Topic Questions: 3 explain why redshift leads to the idea that the Universe is expanding — 9702 P4 Hubble’s law and the Big Bang theory

> 4 9702 P4 Hubble’s law and the Big Bang theory topic questions (8 marks) on 3 explain why redshift leads to the idea that the… — 4 papers, 2025–2026. Open…

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CIE IAL · Physics · 9702 P4 · Hubble’s law and the Big Bang theory

4 9702 P4 Hubble’s law and the Big Bang theory topic questions are tagged to this syllabus point across 4 papers (2025–2026). Only the parts whose knowledge graph matches this syllabus statement are counted, and the table shows which parts of each question are involved.

- 4 topic questions
- 4 papers
- 8 tagged marks
- 30.8% of topic questions
- 29.6% of topic marks
- 2025–2026
- Syllabus 2025–2027
- [All 9702 P4 Hubble’s law and the Big Bang theory topic questions](https://www.examsci.com/topics/cie-ial/physics/9702-paper-4/hubble-s-law-and-the-big-bang-theory/)
- [All paper codes](https://www.examsci.com/topics/)

Core finding

**This Hubble’s law and the Big Bang theory syllabus point appears in 4 9702 P4 papers across 2025–2026, contributing 4 topic questions and 8 marks.** The most recent appearance is 9702/44 May/June 2026. That equals 30.8% of the 13 topic questions and 29.6% of the 27 marks tagged to Hubble’s law and the Big Bang theory. 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 |
| --- | --- | --- | --- | --- | --- | --- |
| [**9702/44** May/June 2026 · CIE IAL](https://www.examsci.com/past-papers/cie-ial/physics/9702-paper-4/2026-may-june-9702-44/#q-10) | **Q10** Standard Candles, Redshift and Stellar Radii - CIE A-Level Physics 2026 Jun Paper 44 Q10 | FRQ | 1 of 5 parts ((b)(i)) | 2 of 7 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=92110ebb-9742-4a78-840d-cc028724e060&question_id=8f012870-ee94-4cb6-af73-ef6c641c41b7&source_detail=9702%2F44+May%2FJune+2026) |
| [**9702/44** October/November 2025 · CIE IAL](https://www.examsci.com/past-papers/cie-ial/physics/9702-paper-4/2025-october-november-9702-44/#q-10) | **Q10** Cosmological Redshift and Hubble's Law - CIE A Level Physics 2025 Nov Paper 44 Q10 | FRQ | 1 of 3 parts ((b)) | 2 of 7 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=188bcbde-77c7-4443-9dec-bdf3fb0f0df1&question_id=acec3b31-cc7f-47ca-af3d-098c0c67b500&source_detail=9702%2F44+October%2FNovember+2025) |
| [**9702/41** May/June 2025 · CIE IAL](https://www.examsci.com/past-papers/cie-ial/physics/9702-paper-4/2025-may-june-9702-41/#q-10) | **Q10** Redshift and Hubble's Law for a Distant Star - CIE Physics 2025 Jun Paper 41 Q10 | FRQ | 1 of 5 parts ((b)(i)) | 2 of 10 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=9e2dee21-081d-42d0-8bb9-5baea4db8b62&question_id=3682a0d1-6e0c-47e4-a60d-3268e1c4fe88&source_detail=9702%2F41+May%2FJune+2025) |
| [**9702/43** May/June 2025 · CIE IAL](https://www.examsci.com/past-papers/cie-ial/physics/9702-paper-4/2025-may-june-9702-43/#q-10) | **Q10** Hubble's Law, Redshift and Wien's Law - CIE Physics 2025 Jun Paper 43 Q10 | FRQ | 1 of 5 parts ((b)(i)) | 2 of 10 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=9f1b5e88-c15d-4a93-b176-b396f91108d9&question_id=2dd9ebb6-93a9-40df-b703-c1f050cdfc8c&source_detail=9702%2F43+May%2FJune+2025) |

## Related topic questions in Hubble’s law and the Big Bang theory

- [1 understand that the lines in the emission and absorption spectra from distant objects show an increase in wavelength from their known values](https://www.examsci.com/topics/cie-ial/physics/9702-paper-4/hubble-s-law-and-the-big-bang-theory/1-understand-that-the-lines-in-the-emission-and-absorption-spectra-from-distant/) — 4 question items · 4 papers — 8 marks · 2025–2026
- [2 use $\Delta\lambda / \lambda \approx \Delta f / f \approx v / c$ for the redshift of electromagnetic radiation from a source moving relative to an observer](https://www.examsci.com/topics/cie-ial/physics/9702-paper-4/hubble-s-law-and-the-big-bang-theory/2-use-delta-lambda-lambda-approx-delta-f-f-approx-v-c-for-the-redshift-of/) — 4 question items · 4 papers — 8 marks · 2025
- [4 recall and use Hubble’s law $v \approx H_0 d$ and explain how this leads to the Big Bang theory (candidates will only be required to use SI units)](https://www.examsci.com/topics/cie-ial/physics/9702-paper-4/hubble-s-law-and-the-big-bang-theory/4-recall-and-use-hubble-s-law-v-approx-h-0-d-and-explain-how-this-leads-to-the-big/) — 5 question items · 3 papers — 11 marks · 2025

## Topic question rules and edge cases

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

4 question stems cover this subtopic across 4 papers, but only 4 tagged parts and 8 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 2025–2026. 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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