You may use a calculator. You should show all your working and use appropriate units. Take the weight of 1.0 kg to be 9.8 N (acceleration of free fall = 9.8 m/s²).
(a)(i)
Fig. 8.1 shows a circuit containing a 230 V a.c. supply connected to a television and two lamps.
In normal operation, both switches are closed. The power supplied to each lamp is 40 W and the power supplied to the television is 120 W.
Calculate, in normal operation:
the total number of kilowatt-hours (kW h) of energy supplied to the circuit in 1.0 hour
number of kW h = ...........................................................
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]
(a)(ii)
Calculate, in normal operation, the current in each lamp.
current = ........................................................ A
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)
Explain why the switches are placed in the live wire and not in the neutral wire.
Answer guidance
Explain Give reasons, not just what happens. Each distinct reason is usually worth a mark.
[2 marks]
(c)
State one advantage of connecting the two lamps in parallel in this circuit.
Answer guidance
State A short answer. No explanation is needed, and adding one cannot earn extra marks.
[1 mark]
5054/02/SP/23Cambridge O Level Physics 5054 · Specimen 2023 · Paper 2 · Question 8