A body constrained to move along the z -axis of a coordinate system is subject to a constant force F given by `vec(F) =(-hat(i)+2hat(j)+3hat(k))N` where `hat(i),hat(j),hat(k)` are unit vectors along the x, y and z-axis of the system respectively . What is the work done by this force in moving the body a distance of 4 m along the z- axis?

Explanation

`W =vec(F).vec(d)`
`=(hat(i)+2hat(j)+3hat(k)).(4hat(k))`
=12 J