A food mixer takes a current of 2.0 A from a 230 V supply. It transfers energy usefully at 350 J/s. What is the rate of unwanted energy transfer?
460 W460\ \mathrm{W}460 W
110 W110\ \mathrm{W}110 W
115 W115\ \mathrm{W}115 W
810 W810\ \mathrm{W}810 W
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.