A powered trolley moves theatre scenery along a straight track in two stages. Its input power is constant at 2.0 kW throughout the journey. In each stage, the constant driving force acts in the direction of motion.
| Stage | Driving force in N\mathrm{N}N | Distance moved in m\mathrm{m}m | Time taken in s\mathrm{s}s |
|---|---|---|---|
| 1 | 700 | 15 | 8.0 |
| 2 | 500 | 25 | 12.0 |
Calculate the mean power dissipated by the trolley during the complete journey.