1. Energy Forms and Transformations

2. Forms of Energy

3. Mechanical Energy Associated with the position and motion of an object. A combination of an object’s PE and KE (total energy of the object at any one time) An object with ME can do work on another object. ME = the ability to do work The more ME, the more work an object can do

4. Calculating ME ME = PE + KE Sometimes an object’s ME is just its potential energy and sometimes it is just its kinetic energy.

5. At one point during the Super Bowl, the football had a GPE of 32 J and a KE of 45 J. What was the ball’s ME? ME = PE + KE ME = 32J + 45J ME = 77J

6. Other Forms of Energy Potential, Kinetic, and Mechanical are 3 types of energy that deal with the motion and position of an object. There are several other types of energy that are associated with the particles of objects.

7. Thermal Energy The particles that make up objects are called atoms and molecules. They are always in motion. The total kinetic and potential energy of the molecules and atoms in an object is its thermal energy.

8. Friction Friction turns mechanical energy into thermal energy Energy “lost” due to friction still exists – it is now the energy of heat!

9. Electrical Energy Electrical energy results from the movement of charged particles. It can either be kinetic or potential depending on whether the charges are moving or stored.

10. Chemical Energy Everything is made of chemical compounds (which are made up of atoms and molecules bonded together). Chemical energy comes from the bonds of chemical compounds. Breaking and reforming those bonds releases and reorganizes energy. Example: Food!

11. Nuclear Energy Stored in the nucleus (center) of atoms… released during a nuclear reaction Nuclear Fission: Splitting the nucleus (Nuclear Power Plants  electricity) Nuclear Fusion: Nuclei join together (Sun)

12. Electromagnetic Energy Travels in waves that have some electrical properties and some magnetic properties (hence the name!) All from the sun (although manmade machines can produce them as well) Examples: microwave, X-rays, radio wave, sunlight

13. *Law of Conservation of Energy* Energy cannot be created or destroyed …but it can be transferred and transformed! The total amount of energy before any transformation is equal to the total amount of energy after

14. What’s the difference? Energy Transformation: Change from one form of energy to another form. Energy Transfer: Energy goes from one object to another as the same form.

15. Transform/Transfer Pictures Transfer kinetic energy from player to ball Chemical energy of food transformed to kinetic energy of boy

16. Transformations single transformation : toaster electrical energy to thermal energy

17. Transformations multiple transformations: a match Striking match (mechanical) causes friction (thermal) this releases the chemical energy in the match which creates fire (thermal and electromagnetic (light))

18. A Common Energy Transformation Kinetic Energy to Gravitational Potential Energy When does this happen? –When a basketball is tossed up –When a person jumps up and down Gaining GPE Losing KE Gaining KE Losing GPE