Two lamps give out exactly the same amount of light energy each second. Lamp 1 takes 60 J from the supply each second. Lamp 2 takes 15 J from the supply each second. Which statement is correct?
lamp 2 is more efficient, because it wastes less energy each second
lamp 1 is more efficient, because it takes in more energy each second
both lamps are equally efficient, because the light output is the same
lamp 1 is more efficient, because it gives out more energy each second
40 exam-style questions on AQA GCSE Physics 1.2 Conservation and dissipation of energy, covering 1.2.1 Energy transfers in a system and 1.2.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.