A workshop records the use of two electrical devices during one maintenance job.
| Device | Power rating | Total time switched on |
|---|---|---|
| soldering iron | 50 W | 30 minutes30\ \mathrm{{minutes}}30 minutes |
| air compressor | 1.0 kW | 60 s |
Which comparison of the total energy transferred by the devices is correct?
The soldering iron transfers more energy, and the difference is greater than the energy transferred by the air compressor.
The air compressor transfers more energy, and the difference is smaller than the energy transferred by the soldering iron.
The air compressor transfers more energy, and the difference is greater than the energy transferred by the soldering iron.
The soldering iron transfers more energy, and the difference is smaller than the energy transferred by the air compressor.
128 exam-style questions on Edexcel GCSE Physics 8.3 Power and efficiency, covering 8.3.1 Power and 8.3.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.