A motor transfers energy to a pump. The motor is 80% efficient. The pump transfers 75% of the energy it receives into the useful energy store of the water.
The motor receives 2400 J.
How much energy is dissipated by the motor and pump in total?
480 J480\ \mathrm{J}480 J
1080 J1080\ \mathrm{J}1080 J
1440 J1440\ \mathrm{J}1440 J
960 J960\ \mathrm{J}960 J
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.