Physics (AS & A Level) · Oct / Nov 2016 · Paper 12 · Question 38

In the circuit below, P is a potentiometer of total resistance 10 Ω and Q is a fixed resistor of resistance 10 Ω. The battery has an e.m.f. of 4.0 V and negligible internal resistance. The voltmeter has a very high resistance. The slider on the potentiometer is moved from X to Y and a graph of voltmeter reading V is plotted against slider position. Which graph is obtained?

1. AGraph A: V decreases linearly from 4 to 2 as slider moves from X to Y
2. BGraph B: V increases linearly from 0 to 4 as slider moves from X to Y
3. CGraph C: V decreases linearly from 4 to 0 as slider moves from X to Y
4. DGraph D: V increases linearly from 2 to 4 as slider moves from X to Y

As printed in the paper