A supply transfers 60 W to a circuit containing a motor and connecting wires. The wires have a total resistance of 0.50 Ω and carry 2.0 A. A replacement supply and wires transfer the same 60 W, but the current is 1.0 A and the wire resistance is 0.25 Ω. How much greater is the electrical power reaching the motor?
2.00 W2.00\ \mathrm{W}2.00 W
1.75 W1.75\ \mathrm{W}1.75 W
1.00 W1.00\ \mathrm{W}1.00 W
0.25 W0.25\ \mathrm{W}0.25 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.