posted by brl .
a 840 N crate rests on the floor how much work is required to move it at constant speed 5.5m along the floor against a friction force 180 N?
The force required to move the crate at constant speed should just be greater than the frictional force.
F (ext.)= 180 N
Work done = F*s = 180*5.5 = 990 J