An electric winch is being used to lift cargo crates from the dock to the deck of a boat.
Calculate the work done when a crate with a weight of 0.8 kN0.8\text{ kN}0.8 kN is lifted a vertical distance of 1.5 m from the dock.
Use the equation:
work done=force×distance \text{work done} = \text{force} \times \text{distance} work done=force×distanceThe power of the electric winch is 80 W.
Calculate the time taken for the winch to lift the crate.
Use the equation:
power=work donetime taken \text{power} = \frac{\text{work done}}{\text{time taken}} power=time takenwork doneThe winch is powered by a 36 V power supply while operating at 80 W.
Calculate the current flowing through the winch motor while it is in use.
Use the equation:
power=potential difference×current \text{power} = \text{potential difference} \times \text{current} power=potential difference×currentGive your answer to 2 significant figures.