Work

1
Work Power
2
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)

3

• 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.

4
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.

5

• Horsepower average power output of a draft
  horse.
• 1 horsepower 746 watts.