A motor raises a 24 kg load through 2.5 m in 8.0 s. Its efficiency is 0.60. Gravitational field strength is 10 N/kg. What is its mean input power?
1000 W1000\ \mathrm{W}1000 W
45 W45\ \mathrm{W}45 W
125 W125\ \mathrm{W}125 W
75 W75\ \mathrm{W}75 W
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.