A rescue helicopter hoists a medical equipment crate of mass 85 kg from the ground to a ledge at a height of 45 m. The crate is lifted at a constant vertical speed of 2.4 m s-1.
What is the minimum power that the helicopter's hoist motor must deliver to lift the crate?
0.20 kW0.20\text{ kW}0.20 kW
2.0 kW2.0\text{ kW}2.0 kW
16 kW16\text{ kW}16 kW
38 kW38\text{ kW}38 kW
13 exam-style questions on OCR A A Level Physics Work, energy and power, covering Work and conservation of energy, Kinetic and potential energies, and Power. Each one has a worked solution and a mark scheme showing where the marks go.