A garden fountain pump runs from a 12 V supply. The pump transfers energy usefully to the water at a rate of 7.2 W. Energy is wasted to the surroundings at a rate of 10.8 W.
What is the current in the pump?
0.60 A0.60\ \mathrm{A}0.60 A
1.5 A1.5\ \mathrm{A}1.5 A
0.30 A0.30\ \mathrm{A}0.30 A
0.90 A0.90\ \mathrm{A}0.90 A
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.