as $0.5 \\times 0.45 \\times 16$ A1\n- Obtains the correct final answer of $3.6\\text{ J}$ (or $3.6$) A1","marks":3,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"kinetic_energy_formula","label":"Use the kinetic energy formula","steps":[{"type":"text","order":1,"title":"Choose the equation","content":"Kinetic energy is the energy an object has because it is moving. Use\n\n$$E_k=\\frac{1}{2}mv^2$$\n\nwhere $m$ is mass in kilograms and $v$ is speed in metres per second. The values are already in the correct units.","highlights":[{"text":"mass $0.45\\text{ kg}$","location":"specification"},{"text":"speed is $4.0\\text{ m/s}$","location":"specification"}]},{"type":"hyper_latex","block":{"nodes":[{"latex":"E_k=\\frac{1}{2}mv^2"},{"latex":"E_k=\\frac{1}{2}\\times\\htmlData{anchor=mass-used}{0.45}\\times\\htmlData{anchor=speed-used}{4.0}^{2}"}],"highlights":[{"color":"sky","style":"box","anchor":"mass-used"},{"color":"orange","style":"box","anchor":"speed-used"}]},"order":2,"title":"Substitute the values","description":"Use the kinetic energy formula, where m is mass and v is speed. M1: substitute m = 0.45 kg and v = 4.0 m/s."},{"type":"hyper_latex","block":{"nodes":[{"latex":"\\htmlData{anchor=speed-squared}{4.0^2}=\\htmlData{anchor=sixteen}{16}"},{"latex":"E_k=\\frac{1}{2}\\times0.45\\times\\htmlData{anchor=sixteen-used}{16}"}],"highlights":[{"color":"orange","style":"box","anchor":"speed-squared"}],"connections":[{"to":"sixteen-used","from":"sixteen","color":"green","label":"substitute 16"}]},"order":3,"title":"Square the speed","description":"Square the speed before completing the multiplication. A1: 4.0 squared = 16."},{"type":"hyper_latex","block":{"nodes":[{"latex":"E_k=\\frac{1}{2}\\times0.45\\times16"},{"latex":"\\boxed{\\htmlData{anchor=answer}{E_k=3.6\\ \\mathrm{J}}}"}],"highlights":[{"color":"green","style":"box","anchor":"answer"}]},"order":4,"title":"Give the kinetic energy","description":"Multiply the three factors and include the unit J, for joules. A1: Ek = 3.6 J."}]}],"generatedAt":"2026-07-22T11:43:17.698Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"c8c0a17f-e3a1-4e91-aa44-5ceeff2123c5","revisionId":"9173bae7-4504-4d29-a7a2-1c9a5892c629","questionNumber":null,"questionType":"LA","specification":"An experimental drone of mass $4.8\\text{ kg}$ is flying horizontally in a straight line.","difficulty":2,"difficultyBand":"easy","totalMarks":3,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"36e0981b-179f-44ed-bc98-ad8be3873284","label":null,"content":"Calculate the kinetic energy of the drone when it is travelling at a constant speed of $12.5\\text{ m/s}$.\n\nUse the equation:\n$$\\text{kinetic energy} = 0.5 \\times \\text{mass} \\times \\text{speed}^2$$","markscheme":"- Identifies mass $m = 4.8\\text{ kg}$ and speed $v = 12.5\\text{ m/s}$, substituting into the formula to get $0.5 \\times 4.8 \\times 12.5^2$ M1\n- Calculates the square of the speed: $12.5^2 = 156.25$ M1\n- Obtains the final kinetic energy of $375\\text{ J}$ A1","marks":3,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"substitute_formula","label":"Substitute into the formula","steps":[{"type":"hyper_latex","block":{"nodes":[{"latex":"E_k=0.5\\times \\htmlData{anchor=mass_symbol}{m}\\times \\htmlData{anchor=speed_symbol}{v}^{2}"},{"latex":"E_k=0.5\\times \\htmlData{anchor=mass_value}{4.8}\\times \\htmlData{anchor=speed_value}{12.5}^{2}"}],"highlights":[{"color":"sky","anchor":"mass_value"},{"color":"amber","style":"box","anchor":"speed_value"}]},"order":1,"title":"Substitute the values","description":"Use the given mass m = 4.8 kg and speed v = 12.5 m/s. Replace m with 4.8 and v with 12.5 in the formula; this substitution earns the first method mark."},{"type":"hyper_latex","block":{"nodes":[{"latex":"v^2 = \\htmlData{anchor=speed-factor}{12.5}\\times 12.5"},{"latex":"v^2 = \\htmlData{anchor=squared-speed}{156.25}"}],"connecti

Energy stores, work done and energy calculations

Question 61

Energy stores, work done and energy calculations Questions

Energy stores, work done and energy calculations

Question 61

Energy stores, work done and energy calculations Questions