1. the BIG idea Energy is transferred when a force moves an object. Work and Energy Work is the use of force to move an object. 4.1 Energy is transferred when work is done. 4.2 Power is the rate at which work is done. 4.3 CHAPTER CHAPTER OUTLINE NEW CHAPTER

2. VOCABULARY KEY CONCEPT CHAPTER HOME Work is done by a force that acts in the same direction as the motion of an object. Work = Force distance 4.1 SECTION OUTLINE SECTION OUTLINE Work is the use of force to move an object. joule work applied force object direction of motion part of force doing work part of force not doing work object applied force direction of motion

3. VOCABULARY KEY CONCEPT CHAPTER HOME The use of force to move an object over a distance. work 4.1 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY joule work Work is the use of force to move an object.

4. VOCABULARY KEY CONCEPT CHAPTER HOME The unit used to measure work; one joule of work is done when a force of one newton moves an object one meter. joule 4.1 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY joule work Work is the use of force to move an object.

5. VOCABULARY KEY CONCEPT CHAPTER HOME Top of Ramp 100% PE 1 At the top of the ramp, the skater’s mechanical energy is equal to her potential energy because she has no velocity. The amounts of potential energy and kinetic energy in a system or process may vary, but the total amount of energy remains unchanged. Energy is transferred when work is done. 4.2 SECTION OUTLINE SECTION OUTLINE kinetic energy mechanical energy conservation of energy potential energy GPE = mgh ME = PE + KE KE = mv 2 1 2

6. VOCABULARY KEY CONCEPT CHAPTER HOME The amounts of potential energy and kinetic energy in a system or process may vary, but the total amount of energy remains unchanged. Energy is transferred when work is done. 4.2 SECTION OUTLINE SECTION OUTLINE kinetic energy mechanical energy conservation of energy potential energy GPE = mgh ME = PE + KE KE = mv 2 1 2 Halfway Down Ramp 2 50% KE 50% PE As the skater goes down the ramp, she loses height but gains speed. The potential energy she loses is equal to the kinetic energy she gains.

7. VOCABULARY KEY CONCEPT CHAPTER HOME The amounts of potential energy and kinetic energy in a system or process may vary, but the total amount of energy remains unchanged. Energy is transferred when work is done. 4.2 SECTION OUTLINE SECTION OUTLINE kinetic energy mechanical energy conservation of energy potential energy GPE = mgh ME = PE + KE KE = mv 2 1 2 Bottom of Ramp 100% KE 3 As the skater speeds along the bottom of the ramp, all of the potential energy has changed to kinetic energy. Her mechanical energy remains unchanged.

8. VOCABULARY KEY CONCEPT CHAPTER HOME Stored energy, or the energy an object has due to its position. potential energy 4.2 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Energy is transferred when work is done. kinetic energy mechanical energy conservation of energy potential energy

9. VOCABULARY KEY CONCEPT CHAPTER HOME The energy of motion; a moving object has the most kinetic energy at the point where it moves the fastest. kinetic energy 4.2 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Energy is transferred when work is done. kinetic energy mechanical energy conservation of energy potential energy

10. VOCABULARY KEY CONCEPT CHAPTER HOME A combination of the kinetic energy and potential energy an object has. mechanical energy 4.2 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Energy is transferred when work is done. kinetic energy mechanical energy conservation of energy potential energy

11. VOCABULARY KEY CONCEPT CHAPTER HOME A law stating that no matter how energy is transferred or transformed, all of the energy is still present in one form or another. conservation of energy 4.2 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Energy is transferred when work is done. kinetic energy mechanical energy conservation of energy potential energy

12. VOCABULARY KEY CONCEPT CHAPTER HOME Power can be calculated from work and time. 4.3 SECTION OUTLINE SECTION OUTLINE Power is the rate at which work is done. watt power horsepower Power = Work time Power can be calculated from energy and time. Power = Energy time Power is measured in watts (W) and sometimes horsepower (hp).

13. VOCABULARY KEY CONCEPT CHAPTER HOME The rate at which work is done. power 4.3 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY watt power horsepower Power is the rate at which work is done.

14. VOCABULARY KEY CONCEPT CHAPTER HOME The unit used to measure power; one watt is equal to one joule of work done in one second. watt 4.3 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY watt power horsepower Power is the rate at which work is done.

15. VOCABULARY KEY CONCEPT CHAPTER HOME The unit of measurement for engines and motors; one horsepower equals 745 watts. horsepower 4.3 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY watt power horsepower Power is the rate at which work is done.

16. VOCABULARY KEY CONCEPT CHAPTER HOME 1. Force, Motion, and Work I. Work is the use of force to move an object. A. Force is necessary to do work. B. Objects that are moving can do work. 2. Calculating Work 4.1 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Work is the use of force to move an object. joule work

17. VOCABULARY KEY CONCEPT CHAPTER HOME II. Energy is transferred when work is done. A. Work transfers energy. C. The total amount of energy is constant. 4.2 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY B. Work changes potential and kinetic energy. 1. Calculating Gravitational Potential Energy Energy is transferred when work is done. 2. Calculating Kinetic Energy 3. Calculating Mechanical Energy 1. Conserving Mechanical Energy 2. Losing Mechanical Energy 3. Forms of Energy kinetic energy mechanical energy conservation of energy potential energy

18. VOCABULARY KEY CONCEPT CHAPTER HOME III. Power is the rate at which work is done. A. Power can be calculated from work and time. 1. Calculating Power from Work B. Power can be calculated from energy and time. 4.3 KEY CONCEPT SUMMARY KEY CONCEPT SUMMARY Power is the rate at which work is done. 2. Horsepower 1. Calculating Power from Energy 2. Everyday Power watt power horsepower