(a) 4.0m along the floor against a friction force of 230 N, and (b) 4.0m vertically?

I’m not sure how to do this problem, and it’d be awesome if someone could explain it step-by-step so I can figure out the others too. Thanks!!

### 2 Answers

part a)

Since the problem states constant speed, the acceleration is zero. The frictional force and the force exerted on the crate by the mover are the forces acting on the crate. The work then is only

W = F*d = 230N*4m = 920 J

part b)

Similar to the above except vertical. The force needed to lift the crate at constant speed vertically is 1300 N. Therefore

W = F*d = 1300N*4m = 5200J

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