Physics (AS & A Level) · May / June 2026 · Paper 14 · Question 36

Which statement about the terminal potential difference (p.d.) of a power supply in a series circuit is correct?

1. AThe difference between the electromotive force (e.m.f.) and the terminal p.d. of the power supply is equal to the total energy dissipated inside the power supply due to its internal resistance.
2. BThe terminal p.d. of the power supply is equal to the e.m.f. when there is no current in the supply.
3. CThe terminal p.d. of the power supply is the energy transferred in moving a unit charge around the complete circuit.
4. DThe terminal p.d. of the power supply is always more than the e.m.f. due to the internal resistance of the supply.

As printed in the paper