Physics (AS & A Level) · May / June 2025 · Paper 12 · Question 37

Each of Kirchhoff's two laws presumes that some quantity is conserved. Which row states Kirchhoff's first law and names the quantity that is conserved?

1. AThe algebraic sum of currents at a junction is zero. / charge
2. BThe algebraic sum of currents at a junction is zero. / energy
3. CThe e.m.f. in a loop is equal to the algebraic sum of the product of current and resistance round the loop. / charge
4. DThe e.m.f. in a loop is equal to the algebraic sum of the product of current and resistance round the loop. / energy

As printed in the paper