How much work is done when a obj is moved 4ft along an incline that rises 5ft every 12ft by force 20Ib @ 30deg

Answer 1

Let i and j be the unit vectors in the x and y directions. The force can be written as F = 10sqrt(3) i + 10 j. The displacement vector can be written as D = 48/13 i + 20/13 j. Thus the work is F (dot) D = 480sqrt(3)/13 + 200/13 with unit lb*ft.