Forces problem with a crate, what's doing the work?

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A crate is pushed at a constant velocity over 5 meters with a friction force of 5 N. The net work done on the crate is zero because the pushing force equals the friction force, resulting in no acceleration. The work done by the friction force is negative, calculated as -25 J, since it acts in the opposite direction to the displacement. The external pushing force does positive work of 25 J to counteract friction. Gravity does no work in this scenario as there is no vertical movement.
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Homework Statement


A crate is pushed along the ground at a constant velocity for a distance of 5m. if the friction force is 5 N, how much net work is done on the crate? how much work is done by the friction force? by the external pushing force? by gravity?


Homework Equations





The Attempt at a Solution


I believe the net work is force 5N x displacement 5m, so 25. there's no movement along the y axis, so I'm thinking gravity's work is zero. but how can i determine how much work is done by the friction force, and how much by the external pushing force?
 
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Hi there,:smile:
Welcome to PF!

yup, work by gravity is 0, but your net work done is wrong...the 5N is the frictional force acting so the work done by friction can be got from this,(remember the displacement is in opposite direction!)

You are also given body is moving with constant velocity, when can the body do that? In what way must forces act ?
 

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