1. Unit 5
Work, Power, and Energy

2. Work (W)
Work is done on an object when a force is applied and the object moves
W = Fd
Unit for work: kg•m2/s2 or Joule (J)

3. Work is done only when the components of a force are parallel to a displacement
W = Fd(cosΘ)
Wnet = Fnetd(cosΘ)

4. Work is a scalar quantity
Can be positive or negative
Positive if your applied force and direction of movement are the same
Ex. Pushing a vacuum
Pulling a wagon
Negative if your applied force is opposite of the direction of movement
Ex. Pushing against a remote control car that is going forward
Pulling against a remote control car that is going in the opposite direction

5. How much work is done on a vacuum cleaner pulled 3
How much work is done on a vacuum cleaner pulled 3.0 m by a force of 50.0 N at an angle of 30.0° above the horizontal?