1. Potential and Kinetic Energy

2. How is all energy divided?
Potential
Energy
Kinetic
Energy
Gravitation
Potential
Energy
Elastic
Chemical

3. What is Potential Energy?
Energy that is stored and waiting to be used later

4. What is Gravitational Potential Energy?
Potential energy due to an object’s position
P.E. = mass x
height x gravity
Don’t look down, Rover!
Good boy!

5. What is Elastic Potential Energy?
Potential energy due compression or expansion of an elastic object.
Notice the ball compressing
and expanding

6. What is Chemical Potential Energy?
Potential energy stored within the chemical bonds of an object

7. What is Kinetic Energy? Energy an object has due to its motion
K.E. = .5(mass x speed2)
KE = 1/2mv2
M = mass (kg)
V = velocity (m/s)
Unit: Joule (J)

8. If an object changes speed then the KE also changes
If the velocity changes then a force must have been applied over a distance
Therefore: work is done on an object to change that object speed.
W = DKE
Fd = ½ m(vf2 - vi2)

9. Bill Nye http://www.youtube.com/watch?v=zTXW9aRO23Y

10. Conservation of Energy
Conservation of Energy – energy can not be created or destroyed but it can change forms
If friction is ignored
ΔPE = ΔKE
If friction is not ignored
ΔPE = ΔKE + heat

11. OR Total energyinitial = total energyfinal
PE I + KE f = PE f + KE I + Wfriction

14. http://www. energyeducation. tx