c","content":"Explain how the student uses the equipment shown to obtain the data. In your answer you should:\n* Include how any extra equipment is used.\n* Explain how the quantities are calculated.","markscheme":"- States that the voltmeter is used to measure potential difference $V$ and the ammeter is used to measure current $I$ B1\n- States that a stopwatch is used to measure the time duration $t$ of the lift B1\n- States that the electrical energy input is calculated using $E_{\\text{input}} = V \\times I \\times t$ B1\n- States that a balance is used to measure the mass $m$ of the suspended weight B1\n- States that a tape measure or metre rule is used to measure the vertical height $h$ that the mass is lifted B1\n- States that the increase in gravitational potential energy store is calculated using $\\Delta E_p = m \\times g \\times h$ B1","marks":6,"order":2,"markingRubric":null,"explanation":{"methods":[{"id":"measure_and_calculate","label":"Measure then calculate","steps":[{"type":"text","order":0,"title":"Use the circuit meters","content":"Read the meters while the winch lifts the mass. The voltmeter, connected in parallel across the motor, measures the potential difference $V$. The ammeter, connected in series, measures the current $I$.\n\nThis identifies both electrical measurements and earns **B1**.","highlights":[{"text":"Explain how the student uses the equipment shown to obtain the data.","location":"specification"}]},{"type":"text","order":1,"title":"Time the lift","content":"Use a stopwatch to measure the time duration $t$ from when the mass starts rising until it reaches its final height.\n\nThis measurement earns **B1**.","highlights":[{"text":"Include how any extra equipment is used.","location":"specification"}]},{"type":"hyper_latex","block":{"nodes":[{"latex":"E_{\\text{input}}=\\htmlData{anchor=voltage}{V}\\times\\htmlData{anchor=current}{I}\\times\\htmlData{anchor=time}{t}"}],"highlights":[{"color":"sky","anchor":"voltage"},{"color":"orange","anchor":"current"},{"color":"green","anchor":"time"}]},"order":2,"title":"Calculate electrical input","description":"Use the potential difference, current and lift time to find the energy transferred electrically to the motor. This earns B1."},{"type":"text","order":3,"title":"Measure mass and height","content":"Before lifting, use a balance to measure the mass $m$ of the suspended weight. Use a tape measure or metre rule to measure the **vertical** height $h$ through which the mass rises.\n\nThese two measurements earn the next two **B1** marks.","highlights":[{"text":"Include how any extra equipment is used.","location":"specification"}]},{"type":"hyper_latex","block":{"nodes":[{"latex":"\\Delta E_p=\\htmlData{anchor=mass}{m}\\times\\htmlData{anchor=gravity}{g}\\times\\htmlData{anchor=height}{h}"}],"highlights":[{"color":"sky","anchor":"mass"},{"color":"orange","anchor":"gravity"},{"color":"green","anchor":"height"}]},"order":4,"title":"Calculate energy gained","description":"Use the mass, gravitational field strength and vertical height to calculate the increase in the mass's gravitational potential energy store. This earns B1."}]}],"generatedAt":"2026-07-22T09:40:49.698Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"71ec5805-4092-4d81-ac6b-bba7b52b34d8","revisionId":"1d166cbd-d5d4-44a7-9e45-a26ff578a441","questionNumber":null,"questionType":"MC","specification":"An electric hoist is used to raise a crate of mass $250\\text{ kg}$ vertically at a constant speed of $1.2\\text{ m s}^{-1}$. The hoist has an efficiency of $75\\%$. Taking $g = 9.8\\text{ m s}^{-2}$, find the total input power of the hoist.","difficulty":6,"difficultyBand":"medium","totalMarks":1,"sourceTitle":null,"calculatorUse":null,"parts":[],"options":[{"id":"d17bba06-ff64-41d2-bf15-29541dcf2e9e","content":"$$2.21\\text{ kW}$","correct":false,"markscheme":"Incorrect. This is obtained by multiply

Power and efficiency

Question 10

Power and efficiency Questions

Power and efficiency

Question 10

Power and efficiency Questions