1. Work and
Energy m m

2. Work Done by a Constant Force
Work = Fd cos(q)

3. Work F q
Fcos(q) d
Work = Fd cos(q)

4. Units of Work System Unit of Work SI newton-meter Joule (J)
cgs dyne-centimeter erg
British foot-pound

5. A net force acts on a moving object vf vi
Work Energy Theorem
A net force acts on a moving object vf vi
Kinetic
Energy F m x

6. vf vi F m x Work Energy Theorem
The net work done on an object by a net force acting on
it is equal to the change in kinetic energy of the object

7. Work done against friction
Friction acts on moving object m m f d

8. Stretching a Spring

9. x F F x kx
Work

10. Object falls in a gravitational field
Work done by gravity
Object falls in a gravitational field m mg h m
Wg = mgh

11. Work and Energy Work done by force (F) = Kinetic energy =
Work done by gravity =
Work done by a spring =
Work done against friction =

12. Gravity/Kinetic Energy
Ball drooped from rest h v

13. Spring/Kinetic Energy
Work done by a spring v m m k x

14. Spring/Friction
Work done by friction
v = 0 m m k x
d = ?

15. Gravity/Kinetic Energym d
vo = 0
V = ? q h
h = d sin(q)

16. END ?