Two capacitors P and Q, each of capacitance C, are connected in series with a battery of e.m.f. 9.0V, as shown in Fig. 6.1. [Figure 6.1] A switch S is used to connect either a third capacitor T, also of capacitance C, or a resistor R, in parallel with capacitor P.

1. (a)Switch S is in position X. Calculate
2. (a)(i)the combined capacitance, in terms of C, of the three capacitors, capacitance = .....................................................[2]
3. (a)(ii)the potential difference across capacitor Q. Explain your working. potential difference = ..................................................... V[2]
4. (b)Switch S is now moved to position Y. State what happens to the potential difference across capacitor P and across capacitor Q. capacitor P: ............................................................................................................................................................................................................................................................................................ capacitor Q: ............................................................................................................................................................................................................................................................................................[4]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.