A hydroelectric power station produces an output power of 60 MW60\ \text{MW}60 MW.
The efficiency of the power station is 0.80.
The water falls through a vertical height of 150 m to reach the turbines.
Gravitational field strength = 10 N/kg
Calculate the mass of water that must flow through the turbines each second.
The density of water is 1000 kg/m3.
Calculate the volume of water that flows through the turbines each second.
Explain why hydroelectric power stations are useful for meeting sudden increases in the demand for electricity.
Give one disadvantage of building a hydroelectric power station.
16 exam-style questions on OCR GCSE Physics 8.2 Powering Earth, covering 8.2.1 Renewable and non-renewable energy resources, 8.2.2 Patterns and trends in energy use, 8.2.3 The national grid, 8.2.4 Step-up and step-down transformers, 8.2.5 Efficiency of the national grid, 8.2.6 Transformers and power transmission at high voltage, 8.2.7 The UK domestic supply, 8.2.8 Direct and alternating potential difference, 8.2.9 Live, neutral and earth wires, and 8.2.10 Dangers of mains electricity. Each one has a worked solution and a mark scheme showing where the marks go.