# Topic Questions: 68 be able to derive the equations for combining resistances in series and parallel using the principles of charge and energy conservation, and be able to use these equations — WPH12 Electric Circuits

> 39 WPH12 Electric Circuits topic questions (118 marks) on 68 be able to derive the equations for combining… — 20 papers, 2019–2026. Open the exact question…

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Edexcel IAL · Physics · WPH12 · Electric Circuits

39 WPH12 Electric Circuits topic questions are tagged to this syllabus point across 20 papers (2019–2026). Only the parts whose knowledge graph matches this syllabus statement are counted, and the table shows which parts of each question are involved.

- 39 topic questions
- 20 papers
- 118 tagged marks
- 14.6% of topic questions
- 18.6% of topic marks
- 2019–2026
- Syllabus 2018–current
- [All WPH12 Electric Circuits topic questions](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/)
- [All paper codes](https://www.examsci.com/topics/)

Core finding

**This Electric Circuits syllabus point appears in 20 WPH12 papers across 2019–2026, contributing 39 topic questions and 118 marks.** The most recent appearance is WPH12/01 January 2026. That equals 14.6% of the 268 topic questions and 18.6% of the 634 marks tagged to Electric Circuits. 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 |
| --- | --- | --- | --- | --- | --- | --- |
| [**WPH12/01** January 2026 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2026-january-wph12-01/#q-15) | **Q15** Rear Window Heater Electrical Analysis - Edexcel IAL Physics Jan 2026 Q15 | FRQ | 2 of 4 parts ((a)(ii), (b)) | 4 of 9 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=f217f3ed-8314-4b5a-a273-52fcc7614327&question_id=43d86c47-b34c-48e3-8fcd-0e9a84dd9115&source_detail=WPH12%2F01+January+2026) |
| [**WPH12/02** January 2026 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2026-january-wph12-02/#q-14) | **Q14** Headlight I-V Characteristics - Edexcel IAL Physics Jan 2026 Q14 | FRQ | 2 of 3 parts ((b)(i), (b)(ii)) | 6 of 9 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=b8583b90-86ed-4ac4-a0d0-fbc38baea73c&question_id=8c3dc112-dcb4-4fda-ac45-57cf18452d5c&source_detail=WPH12%2F02+January+2026) |
| [**WPH12/02** October 2025 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2025-october-wph12-02/#q-18) | **Q18** Power Dissipation in Resistor Networks - Edexcel IAL Physics Oct 2025 Q18 | FRQ | 2 of 3 parts ((a), (b)) | 8 of 12 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=b2ad8e92-c12e-4023-a9f4-c72ce8345efa&question_id=7f6e1b1d-7824-4aec-80a4-fc4763fdacaf&source_detail=WPH12%2F02+October+2025) |
| [**WPH12/01** June 2025 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2025-june-wph12-01/#q-16) | **Q16** Parallel Resistor Circuit and Voltmeter Prediction - Edexcel IAL Physics May 2025 Q16 | FRQ | 2 of 5 parts ((b)(ii), (c)) | 5 of 11 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3315043e-2e64-48db-9a4f-db8056c87e15&question_id=3dd6dbf9-838f-44fd-8a48-3e1db2405d58&source_detail=WPH12%2F01+June+2025) |
| [**WPH12/01** January 2025 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2025-january-wph12-01/#q-6) | **Q6** Three Resistors Circuit and Voltmeter Reading - Edexcel IAL Physics Jan 2025 Q6 | MCQ | MCQ · 1 part | 1 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=e619207f-bc85-4481-9d5b-1fbdc31ada66&question_id=760b51e3-bf7f-45bf-a9f3-7b8bfd35f086&source_detail=WPH12%2F01+January+2025) |
| [**WPH12/01** January 2025 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2025-january-wph12-01/#q-15) | **Q15** Filament Lamp Circuit Analysis - Edexcel IAL Physics Jan 2025 Q15 | FRQ | 1 of 2 parts ((a)) | 4 of 7 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=e619207f-bc85-4481-9d5b-1fbdc31ada66&question_id=b1824d51-b8b0-4424-b228-c30d4f4fd0bb&source_detail=WPH12%2F01+January+2025) |
| [**WPH12/01** October 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2024-october-wph12-01/#q-8) | **Q8** Total Resistance Calculation - Edexcel IAL Physics Oct 2024 Q8 | MCQ | MCQ · 1 part | 1 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=ed4e8373-fe1b-4450-b59f-13747d878e02&question_id=efa7c9a8-1dd9-48ea-9f42-8b2bf9eb92ec&source_detail=WPH12%2F01+October+2024) |
| [**WPH12/01** June 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2024-june-wph12-01/#q-7) | **Q7** Total Equivalent Resistance - Edexcel IAL Physics June 2024 Q7 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=faa19ed2-c4f7-4432-9548-86e4a8a1dac4&question_id=5bef42c4-6307-4f3d-985a-e51751b6c585&source_detail=WPH12%2F01+June+2024) |
| [**WPH12/01** June 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2024-june-wph12-01/#q-14) | **Q14** Resistivity of Heating Panels - Edexcel IAL Physics June 2024 Q14 | FRQ | 2 of 5 parts ((c), (d)) | 7 of 14 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=faa19ed2-c4f7-4432-9548-86e4a8a1dac4&question_id=f27ddb6f-eaaa-4c6c-ba23-209809910157&source_detail=WPH12%2F01+June+2024) |
| [**WPH12/01** January 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2024-january-wph12-01/#q-5) | **Q5** Voltmeter Reading in Cell Circuit - Edexcel IAL Physics Jan 2024 Q5 | MCQ | MCQ · 1 part | 1 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=030444a8-988a-46b6-9902-c76464e7c5f1&question_id=72f0d424-4102-442f-b464-6368c8ecd7e7&source_detail=WPH12%2F01+January+2024) |
| [**WPH12/01** January 2024 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2024-january-wph12-01/#q-19) | **Q19** Solar Cells & Photoelectric Effect - Edexcel IAL Physics Jan 2024 Q19 | FRQ | 1 of 3 parts ((c)) | 5 of 13 on the paper | Hard | [Go to Practice Hub](https://www.examsci.com/practice?set_id=030444a8-988a-46b6-9902-c76464e7c5f1&question_id=2fe74793-e16d-4ce4-9743-925c6f47d3f7&source_detail=WPH12%2F01+January+2024) |
| [**WPH12/01** October 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2023-october-wph12-01/#q-12) | **Q12** Combined Resistance Derivation - Edexcel IAL Physics Oct 2023 Q12 | FRQ | 1 part | 3 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3e216bad-b45b-4b54-ad64-443f4188aa4c&question_id=2bcf26cc-1a31-4c3c-af17-98e694cb315c&source_detail=WPH12%2F01+October+2023) |
| [**WPH12/01** June 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2023-june-wph12-01/#q-16) | **Q16** Car Headlight I-V Characteristics - Edexcel IAL Physics May 2023 Q16 | FRQ | 2 of 4 parts ((b)(i), (b)(ii)) | 6 of 12 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3a8e11e5-0ef0-468b-b140-32d6d8e746b5&question_id=54211ab6-d994-46ea-8442-8fd818e0a593&source_detail=WPH12%2F01+June+2023) |
| [**WPH12/01** January 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2023-january-wph12-01/#q-13) | **Q13** Drift Velocity and Parallel/Series Circuits - Edexcel IAL Physics Jan 2023 Q13 | FRQ | 1 of 2 parts ((a)) | 4 of 8 on the paper | Hard | [Go to Practice Hub](https://www.examsci.com/practice?set_id=44f43e47-e4db-4cf8-926d-d8e4e0a15c3a&question_id=e34d3715-535b-478d-8ae8-74cab08cfe0f&source_detail=WPH12%2F01+January+2023) |
| [**WPH12/01** January 2023 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2023-january-wph12-01/#q-14) | **Q14** Thermistor Investigation - Edexcel IAL Physics Jan 2023 Q14 | FRQ | 1 of 3 parts ((a)(i)) | 3 of 10 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=44f43e47-e4db-4cf8-926d-d8e4e0a15c3a&question_id=6a59e077-c1e5-4285-8fcd-308e01de2384&source_detail=WPH12%2F01+January+2023) |
| [**WPH12/01** October 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2022-october-wph12-01/#q-13) | **Q13** Circuit Analysis and Drift Velocity - Edexcel IAL Physics Oct 2022 Q13 | FRQ | 1 of 4 parts ((a)) | 4 of 10 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=beffb6bb-3877-4d0b-b853-45356f31e525&question_id=85637aef-38c7-4c4b-a813-14a664e0ed94&source_detail=WPH12%2F01+October+2022) |
| [**WPH12/01** June 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2022-june-wph12-01/#q-12) | **Q12** Thermistor Potential Divider Circuit - Edexcel IAL Physics June 2022 Q12 | FRQ | 1 of 3 parts ((a)) | 4 of 8 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3069ad40-1aa5-4af5-a2d4-5c7bfc121c7d&question_id=244ab865-e412-4550-9063-00fc4b2db485&source_detail=WPH12%2F01+June+2022) |
| [**WPH12/01** June 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2022-june-wph12-01/#q-15) | **Q15** Conservation Laws and Internal Resistance - Edexcel IAL Physics June 2022 Q15 | FRQ | 1 of 3 parts ((b)(i)) | 3 of 12 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=3069ad40-1aa5-4af5-a2d4-5c7bfc121c7d&question_id=1d22e1ef-6a29-4fe4-a075-e125b70b37d2&source_detail=WPH12%2F01+June+2022) |
| [**WPH12/01** January 2022 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2022-january-wph12-01/#q-17) | **Q17** Parallel Circuit Calculations and Power Dissipation - Edexcel IAL Physics Jan 2022 Q17 | FRQ | 2 parts ((a), (b)) | 10 | Hard | [Go to Practice Hub](https://www.examsci.com/practice?set_id=272cf6d5-ace3-46e9-81c3-821d84b7c606&question_id=a2988165-fb3a-4170-9b71-538b028d7e00&source_detail=WPH12%2F01+January+2022) |
| [**WPH12/01** October 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2021-october-wph12-01/#q-13) | **Q13** Filament Lamp Resistivity and Circuit Evaluation - Edexcel IAL Physics Oct 2021 Q13 | FRQ | 1 of 2 parts ((b)) | 3 of 7 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=a6a4d67e-15cf-4c88-8068-dbcf14bb868f&question_id=db70bfcd-3bcc-4426-8b5b-0d141eb72205&source_detail=WPH12%2F01+October+2021) |
| [**WPH12/01** October 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2021-october-wph12-01/#q-15) | **Q15** Deriving Parallel Resistance and Combination Evaluation - Edexcel IAL Physics Oct 2021 Q15 | FRQ | 3 parts ((a), (b)(i), (b)(ii)) | 8 | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=a6a4d67e-15cf-4c88-8068-dbcf14bb868f&question_id=cc6bc2d6-a44b-4436-85ae-46bc752e3732&source_detail=WPH12%2F01+October+2021) |
| [**WPH12/01** June 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2021-june-wph12-01/#q-12) | **Q12** Internal Resistance and Chemical Energy - Edexcel IAL Physics June 2021 Q12 | FRQ | 1 of 3 parts ((b)) | 3 of 8 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=1edbe5c1-050a-47b1-b2d3-6cb7932da279&question_id=2620dbe6-c19f-4e4b-a6fe-5507850247c6&source_detail=WPH12%2F01+June+2021) |
| [**WPH12/01** June 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2021-june-wph12-01/#q-18) | **Q18** Resistivity and Power in Circuits - Edexcel IAL Physics June 2021 Q18 | FRQ | 1 of 4 parts ((b)) | 4 of 13 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=1edbe5c1-050a-47b1-b2d3-6cb7932da279&question_id=5467218e-6a9d-479f-aa5a-15a1445f7129&source_detail=WPH12%2F01+June+2021) |
| [**WPH12/01** January 2021 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2021-january-wph12-01/#q-2) | **Q2** Resistor Combination Resistance - Edexcel IAL Physics Jan 2021 Q2 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=0685a005-c20b-4099-9db0-869cf6f6e4cf&question_id=959ef851-2928-4525-8ae6-ed05b433f379&source_detail=WPH12%2F01+January+2021) |
| [**WPH12/01** October 2020 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2020-october-wph12-01/#q-12) | **Q12** Real and Ideal Voltmeter Circuits - Edexcel IAL Physics Oct 2020 Q12 | FRQ | 1 of 2 parts ((b)) | 4 of 6 on the paper | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=30b9f85f-384f-48e3-b52d-af344e695501&question_id=98154a0b-9a4a-41b1-9e00-176e2b7fd1e7&source_detail=WPH12%2F01+October+2020) |
| [**WPH12/01** October 2020 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2020-october-wph12-01/#q-18) | **Q18** Resistor Networks and Filament Lamp Resistance - Edexcel IAL Physics Oct 2020 Q18 | FRQ | 2 of 3 parts ((a), (b)) | 8 of 12 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=30b9f85f-384f-48e3-b52d-af344e695501&question_id=5048655d-d0da-4314-b0dc-e236f73e1742&source_detail=WPH12%2F01+October+2020) |
| [**WPH12/01** January 2020 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2020-january-wph12-01/#q-3) | **Q3** Resistors in Series and Parallel - Edexcel IAL Physics Jan 2020 Q3 | MCQ | MCQ · 1 part | 1 | Easy | [Go to Practice Hub](https://www.examsci.com/practice?set_id=68c06fc7-b8d0-47b8-8712-5b4ad068842c&question_id=5fe7db71-a5d0-4e42-be5c-a5a665586303&source_detail=WPH12%2F01+January+2020) |
| [**WPH12/01** June 2019 · Edexcel IAL](https://www.examsci.com/past-papers/edexcel-ial/physics/physics-unit-2-wph12/2019-june-wph12-01/#q-15) | **Q15** Resistor Combinations and Potential Divider Circuits - Edexcel IAL Physics May 2019 Q15 | FRQ | 2 of 4 parts ((a), (b)) | 6 of 13 on the paper | Medium | [Go to Practice Hub](https://www.examsci.com/practice?set_id=ac1ff5b2-f21b-4af1-906c-a87572cb18c1&question_id=e69942a3-8d09-48ab-85fb-452d45ceb8b0&source_detail=WPH12%2F01+June+2019) |

## Related topic questions in Electric Circuits

- [64 understand that electric current is the rate of flow of charged particles and be able to use the equation $I=\frac{\Delta Q}{\Delta t}$](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/64-understand-that-electric-current-is-the-rate-of-flow-of-charged-particles-and-be/) — 17 question items · 15 papers — 39 marks · 2019–2026
- [65 understand how to use the equation $V=\frac{W}{Q}$](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/65-understand-how-to-use-the-equation-v-frac-w-q/) — 17 question items · 13 papers — 31 marks · 2019–2026
- [66 understand that resistance is defined by $R=\frac{V}{I}$ and that Ohm's law is a special case when $I\propto V$ for constant temperature](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/66-understand-that-resistance-is-defined-by-r-frac-v-i-and-that-ohm-s-law-is-a/) — 20 question items · 14 papers — 55 marks · 2020–2026
- [67a understand how the distribution of current in a circuit is a consequence of charge conservation](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/67a-understand-how-the-distribution-of-current-in-a-circuit-is-a-consequence-of/) — 12 question items · 10 papers — 32 marks · 2020–2025
- [67b understand how the distribution of potential differences in a circuit is a consequence of energy conservation](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/67b-understand-how-the-distribution-of-potential-differences-in-a-circuit-is-a/) — 13 question items · 10 papers — 34 marks · 2020–2025
- [69 be able to use the equations $P=VI$, $W=VIt$ and be able to derive and use related equations, e.g. $P=I^{2}R$ and $P=\frac{V^{2}}{R}$](https://www.examsci.com/topics/edexcel-ial/physics/physics-unit-2-wph12/electric-circuits/69-be-able-to-use-the-equations-p-vi-w-vit-and-be-able-to-derive-and-use-related/) — 42 question items · 21 papers — 117 marks · 2019–2026

## Topic question rules and edge cases

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

28 question stems cover this subtopic across 20 papers, but only 39 tagged parts and 118 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 2019–2026. 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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