An electric drill is connected to a 230 V supply. It operates continuously with a current of 1.8 A for 20 s. During this time, it transfers energy usefully to the rotating drill bit at a rate of 300 J/s.
Calculate the total unwanted energy transfer during the 20 s interval.
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.