1. Forms of Energy

2. QOD What are the 5 types of energy?
Potential Energy and Kinetic Energy are examples of what type of energy?

3. QOD- Answers What are the 5 types of energy?
Mechanical (moving energy)
Chemical
Electromagnetic
Thermal (heat)
Nuclear
Potential Energy and Kinetic Energy are examples of what type of energy?
MECHANICAL ENERGY!

4. Forms of Energy
Mechanical – involves movement or the potential for movement (2 forms)
Potential Energy – stored energy (PE)
-Not moving energy, but potential to move
-“Gravity” is the force acting on an object will move if allowed to
-Impacted by  Mass, Gravity and “Height”
Kinetic Energy - Energy in motion (KE)
Impacted by - Mass and Velocity

5. How Energy is Related to Work…

6. How Energy is Related to Work…
Once the bow is released, what kind of energy is found in the arrow?

7. Equations Potential Energy = (mass)(gravity)(height)
PE = m x g x h
Units of measurement
Mass = kg
Gravity = m/s2
Height = meters
Units for Potential Energy = Kgm2/s2 = Newton meter or a JOULE (J)
Kinetic Energy = (1/2)(mass)(velocity2)
KE= 1/2 mv2
Units for Kinetic Energy = Newton Meters or JOULES(J)

8. Equation Chart…
UPDATE EQUATION CHART WITH POTENTIAL ENERGY AND KINETIC ENERGY :)

9. Examples of PE and KE Roller Coasters Ski Mountains
Make mucho $ on PE & KE (you pay for PE-lift ticket)
Rain Forest Zip-Lines
Water Slides
Pendulums (physicsplace.com)

10. Examples of PE and KE
Can you think of any other real world examples of potential and kinetic energy???

11. Energy is Conserved
“Energy cannot be created or destroyed.”

12. Conservation of Energy
PE + KE = Total Mechanical Energy
Energy can transfer from PE to KE
Like a see saw battle (as one gains the other loses)
Ex: If total energy = 100% at all times
…and there is 25% PE then there would be ___ KE
You can never gain more energy than you started with…
you can’t gain more height without added force!

13. Converting Energy PE --> KE
In Theory… 100% PE converts to 100% KE
So PE = KE
mgh = 1/2 mv2
Can you predict velocity based on height of an object? (hint: solve for velocity)
Velocity = square root of (2*g*h)

14. Energy Analysis Examples
Think Pair Share…
Energy Analysis Examples
(add these problems to your notes)

15. Roller Coaster Physics
Name two of the forces that affect the motion of the car while it moves on the roller coaster.
Describe how the potential and kinetic energy of the car change as the car rolls downhill.
Can the car reach point X on the track? Why or why not?

16. Physics Place Pendulum Fig.
Choose the top middle book (blue/green, 10th ed.)
User: bergmann12
Password: mustangs1
Does the total amount of energy in the swinging pendulum change?
How are PE and KE related?
When the PE is very high, is it possible for the KE to be very high as well?
When the pendulum has a KE of 82% of the total energy, what would you assume the PE of the pendulum to be?

17. Pendulum Calculation
If h = 20 cm and the purple ball has a mass of 10 kg, then what is the PE of this pendulum?
What would be the pendulum’s velocity at the spot where the pendulum is at it’s lowest point?

18. Euler’s Disk What form of energy is occurring here?
When the disk starts, does it have more potential energy or kinetic energy?
Does the disk gain energy as it falls? Support your answer with your thoughts.

19. Hot Wheels Ramp
Suppose the car is at rest at the top of the ramp. Calculate it’s PE and KE.
After the car is rolling down the ramp, calculate it’s PE and KE at the very instant before it is stopped at the bottom of the ramp.

20. Nerf Gun How could you give the darts in the gun PE (2 ways)?
What happens to the PE once you pull the trigger of the gun?

21. Bowling Ball Pendulum Will this demo hurt? Explain your response to #1

22. Penguin Race Physics in Action

23. Penguin Race Questions
What type of energy do the penguins acquire as they climb?
What type of energy do the penguins acquire as they slide down the track?
Work transforms energy from one form to the other. What is doing the work as the penguins slide down the track?
The D cell battery that powers the toy provides what type of energy?
The penguins can climb due to energy supplied by the dry cell battery.
What does the work in this energy
transition?

24. Penguin Race Questions
Energy is conserved in a closed system. Does all of the dry cell energy go into raising the penguins? Why?
Is the energy the penguins “acquire” by climbing to the top of the ladder equal to the total amount of energy at the bottom of the track? Why?
Friction can do work. Lists all places that friction exists in this toy.
Are the penguins at their “terminal velocity” when sliding down the track? How do you know?