Available practice: 71 of 75 marks. Parts 5(a)(ii), 5(b)(i), 11(a) await marking support. Scores cover available parts only. Theory Paper 2: Section A is compulsory and Section B offers a choice of two questions. Four published mark-scheme discrepancies across the two variants are held from automatic marking.
(a)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. Explain what is meant by electromotive force.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[2 marks]
(b)(i)1In the 12 V series circuit of Fig. 9.1, state the relationship between battery current IB and currents I1 and I2 in the 18 Ω and 30 Ω resistors.
[1 mark]
(b)(i)2In the 12 V series circuit of Fig. 9.1, state an equation relating the battery e.m.f. E to potential differences V1 and V2 across the two resistors.
[1 mark]
(b)(ii)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. An 18 Ω resistor and a 30 Ω resistor are connected in series with the battery. Calculate the current in the battery.
Answer guidance
Calculate Show your working. The method can earn marks even when the final value is wrong, and a bare answer often cannot.
[2 marks]
(b)(iii)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. An 18 Ω resistor and a 30 Ω resistor are connected in series with the battery. Calculate the potential difference (p.d.) across the 18 Ω resistor.
Answer guidance
Calculate Show your working. The method can earn marks even when the final value is wrong, and a bare answer often cannot.
[1 mark]
(b)(iv)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. An 18 Ω resistor and a 30 Ω resistor are connected in series with the battery. Calculate the power produced in the 18 Ω resistor.
Answer guidance
Calculate Show your working. The method can earn marks even when the final value is wrong, and a bare answer often cannot.
[2 marks]
(c)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. The resistors obey Ohm’s law. State Ohm’s law and describe one limitation on this law.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[2 marks]
(d)(i)For the wire material in Fig. 9.1, state how resistance R depends on wire length l when cross-sectional area stays constant.
[1 mark]
(d)(ii)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. The resistors are made from the same material, but have different cross-sectional areas and different lengths. State the relationship between the resistance R and the cross-sectional area A of a wire of constant length.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
(e)Fig. 9.1 is a circuit diagram. The electromotive force (e.m.f.) of the battery is 12 V. A resistor is shown in Fig. 9.2 and part of the resistor colour code is shown in Fig. 9.3. State the colour of the bands on the 30 Ω resistor.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[2 marks]
5054/22/M/J/16Cambridge O Level Physics 5054 · May/June 2016 · Paper 2 variant 2 · Question 9