Capacitance — AS & A Level Physics (9702) questions by topic
Capacitance questions here span discharging a capacitor through a resistor and switch, deriving combined capacitance for capacitors in series, and defining parallel-plate capacitance, weighted from 9 to 10 marks in this A Level Physics set.
Calculate, deduce and explain top the command words, with state and determine also common: explain charge transfer between capacitors, not just quote an energy value. 8 real questions from 2023 to 2025 papers sit below. Submitting each attempt for instant marking catches unexplained algebra or an answer expressed outside the required symbols C and V, immediately rather than after the whole derivation is reviewed.
What examiners look for
- Examiners note credit is only awarded for responses expressed in terms of the symbols C and V, not other unexplained variables.
- A recurring criticism is candidates discussing energy instead of addressing charge transfer between capacitors when that is what the question asks.
- A common mistake is stating a capacitor fully discharges without any discussion of where the charge actually goes.
- Reports flag unexplained algebra: candidates must make clear the physics principles underlying an answer, not present working alone.
- Strong answers correctly deduce how a parallel resistor quantitatively affects the gradient of a discharge graph.
May–June 2025, Paper 42
A circuit contains a capacitor of capacitance C and a resistor of resistance R. Initially, the switch is open and the potential difference (p.d.) across the capacitor is 12 V. The…
Answer this question and get it marked →May–June 2024, Paper 41
Fig. 6.1 shows a capacitor of capacitance C connected in series with a resistor of resistance R and a switch. Initially the switch is open and there is a p.d. of 12 V across the…
Answer this question and get it marked →May–June 2024, Paper 42
Two capacitors X and Y are connected in series to a power supply of voltage V, as shown in Fig. 6.1. The capacitance of X is CX and the capacitance of Y is CY. Derive an…
Answer this question and get it marked →May–June 2024, Paper 43
Fig. 6.1 shows a capacitor of capacitance C connected in series with a resistor of resistance R and a switch. Initially the switch is open and there is a p.d. of 12 V across the…
Answer this question and get it marked →October–November 2024, Paper 42
Define the capacitance of a parallel-plate capacitor.
Answer this question and get it marked →February–March 2023, Paper 42
A capacitor, a battery of electromotive force (e.m.f.) 12 V, a resistor R and a two-way switch are connected in the circuit shown in Fig. 5.1. The switch is initially in position…
Answer this question and get it marked →May–June 2023, Paper 42
Two capacitors A and B are connected into the circuit shown in Fig. 5.1. Capacitor A has capacitance C and capacitor B has capacitance 3C. The electromotive force (e.m.f.) of the…
Answer this question and get it marked →October–November 2023, Paper 42
A capacitor C is charged so that the potential difference (p.d.) V across its terminals is 8.0 V. The capacitor is connected into the circuit of Fig. 6.1, in series with a…
Answer this question and get it marked →Other AS & A Level Physics topics
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