An electric hoist takes 1.5 minutes1.5\text{ minutes}1.5 minutes to lift a heavy cargo container. The change in gravitational potential energy of the container is 450 kJ.
What is the useful power output of the hoist?
5.0 kW5.0\text{ kW}5.0 kW
300 kW300\text{ kW}300 kW
675 kW675\text{ kW}675 kW
40 500 kW40\,500\text{ kW}40500 kW
533 exam-style questions on CIE IGCSE Physics 1.7 Energy, work and power, covering 1.7.1a Energy stores and energy transfers, 1.7.1b Conservation of energy, 1.7.1c Kinetic and gravitational potential energy, 1.7.2 Work done, 1.7.3 Energy resources, 1.7.3a Energy resources and electricity generation, 1.7.3b Nuclear fusion as an energy source, 1.7.3c Efficiency of energy transfer, and 1.7.4 Power. Each one has a worked solution and a mark scheme showing where the marks go.