An electrical engineer has produced two components, P and Q. As temperature increases, the resistance of P falls. As temperature increases, the resistance of Q rises. When P and Q are joined in series, their combined resistance stays unchanged as the temperature varies. The two components are connected in series to a power source that provides a constant current. Which statement is correct?
- AIf a temperature change causes the potential difference (p.d.) across P to double, the p.d. across Q will always halve.
- BThe difference between the p.d. across P and the p.d. across Q does not change with temperature.
- CThe p.d. across component P increases as the temperature rises.
- DThe sum of the p.d. across P and the p.d. across Q does not change with temperature.