Physics (AS & A Level) · Feb / March 2020 · Paper 12 · Question 37

In the circuits shown, the cell has negligible internal resistance. Which diagram shows a potential divider circuit that can vary the potential difference (p.d.) across the lamp?

1. ACircuit A: cell with variable resistor in parallel with lamp
2. BCircuit B: cell with variable resistor in series with lamp
3. CCircuit C: potential divider with variable resistor and lamp
4. DCircuit D: potential divider with variable resistor and lamp

As printed in the paper