Answer :
Given data:
A force exerts by forklift on the box,
[tex]F=300.0\text{ N}[/tex]The displacement of box,
[tex]d=15\text{ m}[/tex]The formula of work done is as follows:
[tex]W=Fd\cos \theta[/tex][tex]\text{Here, }\theta\text{ is an angle betw}een\text{ force and displacement}[/tex]In the given case,
Box is moving in forward direction (horizontal direction) and gravitation force exerts on a box is in the downwards direction.
Therefore, an angle between gravitataional force and displacement of box is,
[tex]\theta=90^o[/tex]Substitute known values in above equation;
[tex]\begin{gathered} W=Fd\cos 90^o \\ W=0\text{ J} \end{gathered}[/tex]Therefore, the work done by forklift against the gravity is 0 J