ndex":5,"initialQuestionWindow":[{"id":"13d7207f-217e-4724-a103-6aa324d99b13","revisionId":"f2738ded-aebb-4476-ac2e-2c26ca89b2ef","questionNumber":null,"questionType":"LA","specification":"An array of five identical ceramic heating elements is connected in series across a stable $40\\text{ V}$ DC power supply, as shown in the circuit diagram below.\n\n![Circuit Diagram](https://assets.mathsgenie.co.uk/aqa-qb/361807dc-452d-4b5f-9e13-595dea2300fe.png)\n\nThe thermal power output of each ceramic heating element is $3.2\\text{ W}$.","difficulty":6,"difficultyBand":"medium","totalMarks":4,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"7da80830-14b0-4997-a72d-dae863d7139f","label":null,"content":"Calculate the resistance of each heating element.","markscheme":"- Calculates the potential difference across a single heating element: $V = \\frac{40\\text{ V}}{5} = 8\\text{ V}$ M1\n- Uses a valid formula relating power, voltage, and resistance, e.g. $P = \\frac{V^2}{R}$ or both $P = I \\times V$ and $R = \\frac{V}{I}$ M1\n- Substitutes values to find the correct numerical resistance of $20$ A1\n- States the correct unit of $\\Omega$ (or ohms) B1","marks":4,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"voltage_division_and_power","label":"Share voltage then use power","steps":[{"type":"hyper_latex","block":{"nodes":[{"latex":"V_{\\mathrm{element}}=\\frac{40\\ \\mathrm{V}}{5}"},{"latex":"V_{\\mathrm{element}}=8\\ \\mathrm{V}"}]},"order":0,"title":"Divide the supply voltage","description":"The five identical elements are in series, so they share the supply potential difference equally. This earns M1."},{"type":"hyper_latex","block":{"nodes":[{"latex":"P=\\frac{V^2}{R}"},{"latex":"R=\\frac{V^2}{P}"}]},"order":1,"title":"Rearrange the formula","description":"Use the power equation for one heating element, then make resistance the subject. Writing this valid relationship earns M1."},{"type":"hyper_latex","block":{"nodes":[{"latex":"R=\\frac{(8\\,\\mathrm{V})^2}{3.2\\,\\mathrm{W}}"},{"latex":"R=20\\,\\Omega"}]},"order":2,"title":"Substitute the values","description":"Substitute the voltage across one element and its power output. Obtaining 20 earns A1; stating ohms earns B1. This is the resistance of each heating element, not the combined resistance."}]}],"generatedAt":"2026-07-22T11:56:32.517Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"1783d899-5c48-4ff7-af0c-67a8ce6957a0","revisionId":"066d5877-4ccc-4675-b3e1-a964cd1dfcc5","questionNumber":null,"questionType":"LA","specification":"A student tests a small electric motor designed for a toy car.\n\nWhen connected to a $6.0\\text{ V}$ battery, the current in the motor is $800\\text{ mA}$.","difficulty":5,"difficultyBand":"medium","totalMarks":3,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"5f3f3677-104c-45a5-9444-2c06fe30da66","label":null,"content":"Calculate the energy transferred to the motor in $5\\text{ minutes}$.\n\nUse an equation selected from the physics equations sheet.","markscheme":"- Converts current to $0.8\\text{ A}$ or time to $300\\text{ s}$ B1\n- Substitutes converted values into $E = V \\times I \\times t$ (e.g. $E = 6.0 \\times 0.8 \\times 300$) M1\n- Calculates a final energy of $1440\\text{ J}$ (or $1.44\\text{ kJ}$) A1","marks":3,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"electrical_energy","label":"Electrical energy calculation","steps":[{"type":"text","order":1,"title":"Convert the current","content":"The battery provides $6.0\\text{ V}$, the motor current is $800\\text{ mA}$ and the time is $5\\text{ minutes}$. Convert the current to amperes:\n\n$$800\\text{ mA}=0.8\\text{ A}$$\n\nThis conversion earns **B1**. (You could instead convert the time to $300\\text{ s}$.)","highlights":[{"text":"$$800\\text{ mA}$","location":"specification"},{"text":"$$5\\text{ minutes}$","location":"specification"}]},

Electrical power

Question 1

Electrical power Questions

Electrical power

Question 1

Electrical power Questions