Answer to Question #84601 in Physics for denise

Question

What is the work done by a crane lifts a steel girder weighing 3 kn through a height of 20 metres?

Answer 1

The work done by definition

W=Fs cos⁡θ

In our case

F=mg=3 kN,s=20 m,θ=0°

So

W=3 000 N×20 m×cos⁡〖0°=60 000〗 J=60 kJ