A construction crane lifts a bundle of steel rods of mass steadily from ground level…
PHYSICS · Subjective · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A construction crane lifts a bundle of steel rods of mass 500kg steadily from ground level to the roof of a building 20m high in 40s. The crane is powered by a diesel engine whose overall efficiency is 25%.
(a) Calculate the gravitational potential energy gained by the load after one lift.
(b) Determine the average power output delivered to the load during the lifting process.
(c) Using the given efficiency, estimate the actual power that the engine must develop to perform this task.
(d) If the engine consumes diesel at the rate of 0.20kg per minute while working at this power, find the mass of diesel used for lifting 30 such loads.