2. ENERGY Above and beyond PE & KE

3. THE LAW: CONSERVATION OF ENERGY ∑ E1 =∑E2 Energy cannot be created or destroyed; it only changes form Energy in = energy out Heat, light and sound are common forms of energy transfer

4. Many types of Energy Mechanical (PE & KE) Gravitational Kinetic Chemical Nuclear Electromagnetic Thermal

5. Mechanical Energy A object that is able to do work has mechanical energy Examples: Cars, trains, tractors, hammers, etc

6. Kinetic Energy (KE) The energy of motion KE=1/2mv 2 Expressed as Joules (J) Example: Book falling from shelf

7. Potential Energy (PE) Stored energy “The energy of position in a force field” PE=mgh Example: Book on a shelf aka: gravitational energy

8. Thermal Energy When the amount of heat added to a system and something happens to the system, Thermal Energy is to blame Expressed as ΔQ Example: Heat added to water activates the water molecules, increasing the KE of the system

9. Chemical Energy When certain chemicals combine, energy is released Most important source of energy right now Example: Combustion of glucose (sugar) in our bodies C 6 H 12 O 6 +6O 2 6CO 2 + 6H 2 O + 690 kcal/mole

10. Electromagnetic Energy Waves transporting energy from one point to another Rapid variation of electric and magnetic field Examples: radio waves, microwaves, infrared radiation, visible light, ultraviolet, x-rays, gamma rays, etc

11. Electrical energy Energy due to the separation of charges Example: electricity!

12. Nuclear Energy aka mass energy E= mc 2 Einstein first observed that anything with mass has energy Unstable isotopes can be fused or split thus liberating the energy within Examples: Fission & fusion

13. Nuclear Energy (cont’d) An incredibly small amount of mass has an incredibly large amount of energy Energy=mass x speed of light squared Speed of light = 3 x 10 8 m/s 50 grams of mass has potential to level an entire city

14. Elastic/Spring PE http://www.sciencejoywagon.co m/physicszone/lessonch/05work/ spring/speng.htmhttp://www.sciencejoywagon.co m/physicszone/lessonch/05work/ spring/speng.htm

15. PROBLEMS: http://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/06/sp.htmlhttp://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/06/sp.html

16. http://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/07/sp.htmlhttp://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/07/sp.html

17. http://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/09/sp.htmlhttp://127.0.0.1:26300/Principles _of_Physics/07_Work,%20Energy %20and%20Power/09/sp.html