A motor has a constant input power of 500 W. The table shows the total useful energy transferred since it was switched on.
| Time in s | Total useful energy in J |
|---|---|
| 0 | 0 |
| 4 | 1000 |
| 10 | 3100 |
What is the efficiency of the motor between 4 s and 10 s?
0.420.420.42
0.700.700.70
0.620.620.62
1.031.031.03
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.