Work & Power
Work Work is done when a force causes a change in the motion of an object. Work = F x d S.I. Units: N x m = Joule (J)
Machines are used to perform work. Ex: 1 J of work = lift an apple (about 1 N) from your waist to the top of your head (about 1 m). Ex: 3 Push-ups require about 1000 J of work.
Power Power represents the amount of time it takes to get work done. Power = Work / time P = W / t S.I. unit of power is watts (w). 1 w = amount of power required to do 1 J of work in 1s.
Horsepower = average power output of a draft horse. 1 horsepower = 746 watts.