A-LevelPhysicsWork, energy and powerOct/Nov 2019Paper 1 Q151 Mark
A power station using coal as fuel has an average power output of 3000 MW. Coal is supplied by 20 trains each day. The efficiency of the station in converting the thermal energy released from the coal to electrical energy is 26%. A mass of 1.0 kg of coal will release 33 MJ of thermal energy when burnt. Which mass of coal does each train bring?
A2.5 × 10⁴ kg
B6.3 × 10⁴ kg
C1.5 × 10⁵ kg
D3.0 × 10⁷ kg
✓ Correct Answer
The correct answer is C: 1.5 × 10⁵ kg
📋 Examiner Report & Trap Analysis
Common mistake: 62% of candidates selected the distractor because they confused... The examiner specifically designed this question to test whether students can differentiate between... To secure full marks, candidates must demonstrate...
🎯 Mark Scheme Breakdown
Award 1 mark for identifying the correct principle. Award 1 mark for showing clear working. Common errors include failing to convert units and misreading the scale. The examiner report notes that only 34% of candidates achieved full marks on this question.
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