Fig. 6.1 illustrates a $240\,\text{V}$ a.c. mains supply linked to a television and two lamps. Under normal operation, each lamp receives $40\,\text{W}$ of power, while the television receives $120\,\text{W}$.
(a(i))[1]
Calculate the total power supplied when the circuit is operating normally.
(a(ii))[2]
Calculate the total energy, in kilowatt-hours (kWh), delivered to the circuit over $3.0$ hours.
(a(iii))[2]
Calculate the current through each lamp.
(b)[2]
Explain why the switches are fitted in the live wire rather than the neutral wire.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “200\text{ W}” …