The table gives results for four machines.
| Machine | Useful work done in J | Time taken in s |
|---|---|---|
| W | 600 | 3.0 |
| X | 800 | 5.0 |
| Y | 900 | 4.0 |
| Z | 1200 | 6.0 |
Which machine has the greatest mean useful power output?
X
W
Y
Z
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.