Two electric drills are tested while drilling the same material.
| Drill | Total energy supplied in J | Useful power output in W | Operating time in s |
|---|---|---|---|
| P | 6000 | 320 | 12 |
| Q | 5400 | 270 | 10 |
By what factor must the efficiency of drill Q be multiplied to give the efficiency of drill P?
1.111.111.11
1.191.191.19
1.281.281.28
0.780.780.78
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.