Potential difference and power: past paper questions

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• Question 31May/June 2026, paper 11Multiple choice1 mark

  What is the definition of the potential difference (p.d.) across a component?

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• Question 31Oct/Nov 2025, paper 11Multiple choice1 mark

  There is a potential difference $V$ across a resistor of resistance $R$. The current in the resistor is $I$. Which equation gives the power $P$ dissipated by the resistor?

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• Question 31Oct/Nov 2023, paper 11Multiple choice1 markHas a diagram

  In the circuit shown, the battery has an electromotive force (e.m.f.) of $6.0\text{ V}$ and negligible internal resistance. The three resistors each have resistance $R$. The total power dissipated in the resistor network is $24\text{ W}$.

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• Question 33May/June 2026, paper 11Multiple choice1 markHas a diagram

  The diagram shows a circuit. Which resistor dissipates the least power?

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• Question 32Oct/Nov 2025, paper 12Multiple choice1 mark

  The current in a resistor of constant resistance is $8.0\text{ mA}$. The power dissipated by the resistor is $P$. The current in the resistor is increased to $12.0\text{ mA}$.

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• Question 35Oct/Nov 2024, paper 11Multiple choice1 markHas a diagram

  The circuit shown contains a cell with negligible internal resistance. The energy transferred per unit charge in driving charge around the complete circuit is $E$.

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• Question 34Oct/Nov 2023, paper 11Multiple choice1 mark

  Which statement about the electromotive force (e.m.f.) of a cell is always correct?

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• Question 30May/June 2026, paper 12Multiple choice1 mark

  There is a current in a resistor for an unknown time. Which two quantities can be used to calculate the energy dissipated by the resistor?

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• Question 34Oct/Nov 2024, paper 13Multiple choice1 mark

  The potential difference (p.d.) across a fixed resistor is $V$. The power dissipated in the resistor is 5.0 W. The p.d. across the resistor then changes to a new value.

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• Question 31Oct/Nov 2023, paper 12Multiple choice1 markHas a diagram

  In the circuit shown, a fixed resistor X is connected in series with a battery and a variable resistor. The power dissipated in resistor X is $7.2\text{ W}$ when a current of $3.0\text{ A}$ passes through it.

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• Question 5Oct/Nov 2025, paper 22Structured11 marksHas a diagram

  Fig. 5.1 shows a circuit containing a battery, two fixed resistors X and Y, and a light-dependent resistor (LDR) Z. The battery has electromotive force (e.m.f.) $5.0\text{ V}$ and internal resistance $4.7\mathrm{\Omega }$. The current in X is $I_1$ and the current in Y is $I_2$.

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• Question 36Oct/Nov 2024, paper 13Multiple choice1 markHas a diagram

  The diagram shows a circuit. Which statement about the circuit is not correct?

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• Question 34May/June 2025, paper 11Multiple choice1 markHas a diagram

  The diagram shows six identical resistors connected in a circuit. In which branch of the circuit is the most power dissipated?

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• Question 5Oct/Nov 2024, paper 22Structured12 marksHas a diagram

  Define electric potential difference (p.d.).

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• Question 6Oct/Nov 2023, paper 21Structured9 marksHas a diagram

  A battery is connected in a circuit with a light-dependent resistor (LDR), two fixed resistors and a voltmeter, as shown in Fig. 6.1. The battery has an electromotive force (e.m.f.) of $25\text{ V}$ and negligible internal resistance.

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• Question 4May/June 2026, paper 22Structured10 marksHas a diagram

  An electric train of mass $1.5\times {10}^4\text{ kg}$ travels up a slope at a constant speed as shown in Figure 4.1. At point X, the train has gravitational potential energy $7.4\text{ MJ}$. At point Y, the train has gravitational potential energy $13.0\text{ MJ}$.

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• Question 32May/June 2024, paper 11Multiple choice1 markHas a diagram

  A kettle is connected to a $250\text{ V}$ mains supply. What are possible values for the power of the kettle and the current in the kettle?

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• Question 7Oct/Nov 2023, paper 41Structured8 marksHas a diagram

  A varying current $I$ passes through a resistor of resistance $R$ in the circuit shown in Fig. 7.1. Fig. 7.2 shows the variation with time $t$ of $I$. The current has magnitude $2I_0$ when it is in the positive direction and $I_0$ when it is in the negative direction.

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• Question 4May/June 2026, paper 23Structured11 marks

  A light-dependent resistor (LDR) is connected across the terminals of a cell that has internal resistance. A voltmeter is connected across the LDR. Draw a circuit diagram to show this arrangement.

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• Question 37May/June 2025, paper 13Multiple choice1 markHas a diagram

  An electrical device of fixed resistance $20\mathrm{\Omega }$ is connected in series with a variable resistor and a battery of e.m.f. $16\text{ V}$ and negligible internal resistance. The power dissipated in the electrical device is $4.0\text{ W}$.

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• Question 29May/June 2024, paper 12Multiple choice1 mark

  What is the definition of potential difference across a component?

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• Question 31May/June 2023, paper 11Multiple choice1 mark

  What is the definition of the potential difference across an electrical component?

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• Question 3May/June 2025, paper 21Structured10 marksHas a diagram

  Define power.

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• Question 36May/June 2024, paper 12Multiple choice1 markHas a diagram

  The diagram shows four identical resistors connected in a circuit. Which resistor dissipates the most power?

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• Question 30May/June 2024, paper 13Multiple choice1 mark

  Which quantity is given by the product of charge and electric potential difference?

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• Question 7May/June 2023, paper 21Structured9 marksHas a diagram

  A battery of electromotive force (e.m.f.) $9.6\text{ V}$ and negligible internal resistance is connected in series with two fixed resistors and a thermistor, as shown in Fig. 7.1. The fixed resistors have resistances of $3400\mathrm{\Omega }$ and $5800\mathrm{\Omega }$.

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