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A-LevelPhysicsD.C. circuitsFeb/Mar 2021Paper 1 Q341 Mark

A fixed resistor and a diode are connected in series to a battery of electromotive force (e.m.f.) 6.0 V and negligible internal resistance. The graph shows the variation with potential difference (p.d.) V of the current I for the diode. [Figure 34.1] The current in the diode is 40 mA. What is the resistance of the fixed resistor?

A30 Ω
B120 Ω
C150 Ω
D180 Ω

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The correct answer is B. This question tests the candidate's understanding of d.c. circuits within the Physicssyllabus. The examiner's mark scheme requires...

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About This A-Level Physics Question

This multiple-choice question appeared in the Cambridge A-Level Physics (9702) Feb/Mar 2021 examination, Paper 1 Variant 2. It tests the topic of D.C. circuits and is worth 1 mark.

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