rmulaUrl":null,"initialIndex":24,"initialQuestionWindow":[{"id":"4e4b3eeb-ef9f-4f64-bc37-4d69a7ce95f1","revisionId":"982906f3-bcef-4dc5-b87e-f6abd3f70606","questionNumber":null,"questionType":"LA","specification":"A student investigates the elastic properties of a latex band used in a model fitness strap. They measure the force applied and the resulting extension as the band is stretched (loaded) and then allowed to contract (unloaded). Their results are plotted on the graph below.\n\n![A force-extension graph for a latex band. The x-axis is labelled 'Extension' and the y-axis is labelled 'Force'. Two curves form a loop: the upper curve is labelled 'Loading' (as the force increases) and the lower curve is labelled 'Unloading' (as the force decreases). The region between the two curves is shaded gray.](https://assets.mathsgenie.co.uk/aqa-qb/b8c91fc8-666b-4b8d-8c16-c540ed69b773.png)","difficulty":7,"difficultyBand":"medium","totalMarks":2,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"d0700f8e-10d5-4e34-a347-82e5de3b547d","label":null,"content":"Suggest what the shaded area between the loading and unloading curves represents.","markscheme":"- Identifies that the shaded area represents energy lost, dissipated, or mechanical work done that is not recovered B1\n- States that this energy is transferred as thermal energy (or heat) to the latex band or surroundings B1","marks":2,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"energy_transfer","label":"Interpret the force-extension loop","steps":[{"type":"text","order":0,"title":"Recall what an area means","content":"On a force-extension graph, the area under a curve represents the **work done**. Work done is an energy transfer.\n\nThe graph already shows the loading and unloading curves, so compare the energy put into the band while loading with the energy returned while unloading.","highlights":[{"text":"Suggest what the shaded area between the loading and unloading curves represents.","location":"specification"}]},{"type":"text","order":1,"title":"Compare the two stages","content":"The loading curve is above the unloading curve. Therefore, more work is done **on** the band while stretching it than the work returned as it contracts.\n\nThe shaded gap is the difference: energy that is **not recovered**. This earns the first mark (B1).","highlights":[{"text":"the shaded area between the loading and unloading curves","location":"specification"}]},{"type":"text","order":2,"title":"Identify the heating","content":"The energy that is not recovered is transferred as **thermal energy** (heating) to the latex band and/or its surroundings. This earns the second mark (B1).","highlights":[{"text":"allowed to contract (unloaded)","location":"specification"}]}]}],"generatedAt":"2026-07-22T11:55:26.288Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"5171cc8b-4599-4893-af04-25e64e2d10ab","revisionId":"7b8b66db-766a-4115-9c24-55b32a32cd5b","questionNumber":null,"questionType":"LA","specification":"","difficulty":5,"difficultyBand":"medium","totalMarks":3,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"eb93fa40-d44f-4bf2-a189-3fcab4f2c220","label":null,"content":"A micro-actuator inside an automated pipette mechanism uses a high-precision alloy spring to control fluid delivery.\n\nDuring a calibration sequence, the work done to compress this spring is $0.36\\text{ J}$.\n\nThe spring constant of the alloy spring is $450\\text{ N/m}$.\n\nCalculate the compression of the spring, giving your answer in metres.","markscheme":"- Recalls or applies the elastic potential energy formula to set up the equation $0.36 = \\frac{1}{2} \\times 450 \\times e^2$ M1\n- Rearranges the equation to find the square of the compression: $e^2 = \\frac{0.36}{225}$ or $e^2 = 0.0016$ M1\n- Obtains the final compression $e = 0.04\\text{ m}$ A1","marks":3,"order":0,"markingRubric":null,"explanation":{"methods":[{"i

Forces and springs

Question 13

Forces and springs Questions

Forces and springs

Question 13

Forces and springs Questions