Question

About 40 J is required to push a crate 4 m across a floor. If the push is in the same direction as the motion of the crate, what is the force on the crate?

Answer 1

I found `F=10N`

Explanation:

Considering no friction, the enrgy is used up entirely to move the crate in the form of work done on the system and it will be:
`W=vecF*vecd=F*d*cos(theta)=`

`40=F*4`
rearranging:
`F=40/4=10N`