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

[alchemist31]

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?

 

[The legend]

Hi there,
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 ?