A 12V battery is in series with an ammeter, a 2Ω fixed resistor and a 0-10Ω variable resistor. High-resistance voltmeters P and Q are connected across the variable resistor and the fixed resistor respectively, as shown. [Figure showing a circuit with a battery, ammeter, fixed resistor, variable resistor, and voltmeters P and Q] The resistance of the variable resistor is changed from its maximum value to zero. Which graph shows the variation with current of the voltmeter readings?
✓ Correct Answer
The correct answer is D: Graph with line P decreasing linearly with current (from maximum), and line Q increasing linearly with current (from minimum).
📋 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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