a. The work motor of the crane did is 60.6 kJ.
b. The average power performed by the crane is 21.263kW.
<h3>What is work done?</h3>
Work done is equal to product of force applied and distance moved.
Work = Force x Distance
Given is a crane at a construction site lifts a concrete block with a mass of m = 277 kg from the ground to the top of a building with a height of h = 22.3 m.
a. Work done by motor is W= F x d
The force is equal to the weight F = mg
So, W = 277 x 9.81 x 22.3
W = 60.6 kJ
Thus, the work done by the motor is 60.6 kJ.
b. The duration of the lift was 2.85 minutes
Power = Work done/ time
Plug the values, we ghave
P = 60.6 x1000 /2.85
P =21.263kW
Thus, the average power performed by the crane is 21.263kW
Learn more about Work done
brainly.com/question/13662169
#SPJ1