An electric winch raises a piece of stage scenery. The dissipated energy includes all the unwanted energy transfers during one lift.
| Energy measurement | Energy / kJ\text{kJ}kJ |
|---|---|
| supplied to the winch | 25.0 |
| dissipated during the lift | 4.5 |
Calculate the efficiency of the winch.
100 exam-style questions on Edexcel GCSE Physics 3.2 Dissipation and efficiency, covering 3.2.1 Dissipation of energy, 3.2.2 Reducing unwanted energy transfers, 3.2.3 Efficiency, and 3.2.4 Increasing efficiency. Each one has a worked solution and a mark scheme showing where the marks go.