3 WorkProduct of force and distance; scalar quantity. W = FdUnit is J named after James Prescott Joule.1 J = 1 N*mWork is done only if object moves in the direction of the applied force.Ex Prob 226 Prac Pr 227

4 Work and Direction of ForceFigure 10-4 p 227 shows work can be broken into its components and that work is done only in the component in which the force is applied.

5 W = Fd cos Since cos 90 = 0, no work is done in the vertical direction.Work done by the friction of grass is negative.Positive work done by you and means you are working.