A motor raises a flood barrier vertically. The barrier has a mass of 120 kg and rises through a vertical height of 0.80 m in 8.0 s. The input power of the motor is 200 W. Gravitational field strength is 10 N/kg.
Calculate the efficiency of the motor as a percentage.
128 exam-style questions on Edexcel GCSE Physics 8.3 Power and efficiency, covering 8.3.1 Power and 8.3.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.