An electric heater contains two identical heating elements connected in parallel.
Each element has a resistance of 46 Ω.
The heater is connected to a 230 V supply. Each element can be switched on separately.
Show that the current in one element is 5.0 A.
Calculate the power of one element.
Both elements are switched on for 15 minutes.
Calculate the energy transferred by the heater.
Give your answer in MJ\text{MJ}MJ.
After many years of use, the resistance of each element has increased. The supply is still 230 V.
Explain the effect of this on the power of the heater.
105 exam-style questions on Edexcel GCSE Physics 10.3 Electrical energy and power, covering 10.3.1 The heating effect of an electric current, 10.3.2 Reducing energy transfer in wires, 10.3.3 Advantages and disadvantages of the heating effect, 10.3.4 Energy transferred by an electrical circuit, 10.3.5 Electrical power, and 10.3.6 Energy transfers in domestic devices. Each one has a worked solution and a mark scheme showing where the marks go.