$7\mathrm{.}84-$ ADDITIONAL PROBLEMS

Points:$1$

A cart is pulled a distance $D$ on a flat, horizontal surface by a constant force $F$ that acts at an angle $$ with the horizontal direction. The other forces on the object during this time are gravity $(F_w),$ normal forces $(F_{N1})$ and $(F_{N2}),$ and rolling frictions $F_{r1}$ and $F_{r2},$ as shown below. What is the work done by each force? Your expression should be in terms of the qiven variables.