1. Kinetic & Potential Energy
Unit 4: Energy
Kinetic & Potential Energy
2015
Pre-test 4 mins
Notes + Videos 20 mins
Start Pre-Lab for Rollercoaster
2014
Notes and Video – about 21 minute (estimate)
+Pre-test Review - 4 minutes
+ Videos - 8 minutes
+ Grades – 10 minute grade review
43 minutes

2. Students will be able to (SWBAT)
Describe different types of potential and kinetic energy.
Date:

3. Energy is a quantity that measures the ability to cause change in a physical system.
Some things that have energy…
Wind (moves things)
You (move)
Batteries (can make things move)
Gasoline (burns to move a car)
A ball at the top of a hill (moves)
Energy

4. Units of Energy The unit for energy is the joule (J). 1 calorie =

5. Potential Energy
Energy an object has due to its condition or position (stored energy).
Example
Snow blower filled with gasoline
Car at the top of a hill
Soccer ball on a table
Spring that is compressed
Stretched rubber band

6. Kinetic Energy Energy an object has due to motion. Examples
Ball rolling off a table
Throwing a ball
Gas molecules bouncing around a room
Skydiver jumping out of a plane

7. What is Kinetic and Potential Energy

8. Where is the energy coming from?1.

9. Types of Potential Energy
Gravitational Potential Energy: energy stored in an object because of where it is placed. It is found in object some height off the ground.

10. Where is the energy coming from?2.

11. Types of Potential Energy
2. Mechanical Potential Energy: energy that is stored by the forces within tension, such as in a rubber band or spring.

12. Where is the energy coming from?3.

13. Types of Potential Energy
Chemical Potential Energy: energy is stored in the bonds between atoms and molecules, such as in photosynthesis.

14. Where is the energy coming from?4.

15. Types of Potential Energy
4. Nuclear Energy : energy stored in the nucleus of an atom. Ex: used in Nuclear power plants
Bryon Power Plant near NIU

16. Where is the energy coming from?
KE 1

17. Types of Kinetic Energy
Radiant Energy : electromagnetic energy that travels in waves. Ex: x-rays, sunlight

18. Where is the energy coming from?
KE 1

19. Types of Kinetic Energy
2. Thermal Energy: vibration and movement of the atoms and molecules within substances. Ex: heat

20. Where is the energy coming from?

21. Types of Kinetic Energy
3. Motion Energy: energy stored in the movement of objects. The faster they move, the more energy is stored.

22. Where is the energy coming from?

23. Types of Kinetic Energy
Sound Energy: movement of energy in waves and produced when a force causes an object or substance to vibrate.

24. Where is the energy coming from?

25. Types of Kinetic Energy
5. Electrical Energy: delivered by tiny charged particles called electrons. EX: Lightning

26. Will E Coyote & Roadrunner 1:22

27. Unit 4 Pre-test Review

28. Students will be able to (SWBAT)
Solve for kinetic energy.
Solve for potential energy.
Solve problems using conservation of energy.
Date:

29. Energy Formulas

30. Solve for Potential and Kinetic Energy
A 2-kg rock falls off a 20 m cliff. When it is halfway down, it is traveling at 14 m/s.
Kinetic energy and potential energy at the top: _______________
Potential Energy half way: ___________
Kinetic energy and potential energy at the bottom: _________________

31. Potential and kinetic energy
Solution:
Kinetic energy at the top: 0 J
Potential energy at the top:
Ep= (2 kg)(9.8 N/kg)(20 m) = 392 J
Potential energy halfway down:
Ep= (2 kg)(9.8 N/kg)(10 m) = 196 J
Kinetic energy at the bottom:
392 J
Potential energy at the bottom:
0 J

32. Law of Conservation of Energy
Energy cannot be created or destroyed
It can only be transformed (changed) from one form to another.
The total amount of energy in the universe never changes.

34. Using and conserving energy
When you “use” energy by turning on a light, you are really converting energy from one form (electricity) to other forms (light and heat).
In the “physics” sense, the energy is not “used up” but converted into other forms of energy.
The total amount of energy stays constant.

35. Objective Review: Solve kinetic and potential energy using conservation of energy.
What is the potential energy of a 2 kg potted plant that is on a 1 m high plant stand?
Ep = mgh
2kg x 9.8m/s 2 x 1m = 19.6 J
What is the kinetic energy of a 3 kg ball that is rolling at 2 m/s?
Ek = ½ mv2
0.5 x 3kg x (2m/s)2 = 6 J

36. Disney Energy --- 7 minutes (EXTRA)