A factory uses an open metal tank of hot water to clean components. An electric heater keeps the water at a constant temperature above room temperature.
Explain why energy must continue to be supplied to the heater and how altering the tank could reduce the energy needed to keep the water at this temperature.
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.