1. Section 1 Changing Energy
Chapter 3 Energy
Section 1 Changing Energy

2. I) Potential and Kinetic Energy

3. A) Energy is the ability to cause changes in matter

4. 1) An object that has energy can apply a force over a distance

5. B) Law of conservation of energy: the total amount of energy is always the same – energy cannot be created or destroyed

6. 1) Example: lamp, electrical energy is turned into light energy

7. C) Kinetic Energy: energy of motion, the ability to exert a force on matter that comes into contact with it

8. 1) the faster the object is moving the greater its kinetic energy, the greater its mass the greater its kinetic energy.

9. 2) a bowling ball and tennis ball moving at the same speed have different kinetic energies ( the bowling ball has greater mass)

10. D) Potential Energy: the energy that is due to the position or condition of an object STORED ENERGY

11. 1) objects lifted higher up have greater potential energy

12. a) the energy used to lift the object is stored in the object

13. b) as an object falls its potential energy is converted into kinetic energy

14. c) the closer an a falling object is to the ground the less potential energy it has and the greater kinetic energy (speed) it has

15. 2) battery is stored chemical energy (chemical to electrical energy)

16. 3) compressed spring is stored energy, as it expands it release mechanical energy

17. 4) water behind a dam is stored energy, the dam opens the water is released changing the energy to mechanical energy

18. E) Potential energy can be changed to Kinetic Energy and Kinetic Energy can be changed to Potential energy

19. 1) example bouncing ball while falling its gaining Kinetic Energy while rising its gaining Potential energy

20. II) Thermal Energy and Heat

21. A) Thermal energy is the kinetic energy of the moving particles of a substance or object

22. 1) the more thermal energy an object has the hotter it is

23. 2) temperature is the measure of thermal energy

24. a) Celsius scale: water freezes at 0 and boils at 100

25. b) Fahrenheit: water freezes at 32 and boils at 212

26. B) Heat: is the transfer of thermal energy

27. 3) thermal energy moves from the object with higher energy to the one with lower energy (hotter object gives heat to the colder object) heat moves from the hotter to the colder

28. a) Ice cubes in water the ice draws the heat from the water.

29. C) Conduction: transfer of thermal energy or heat when two objects touch

30. 1) because the particles in one object collide with, or hit, the particles in the other object, heat is the result of the collision

31. 2) works best through solids like metals

32. 3) conductors are materials that transfer heat well like metals

33. 4) insulators are materials that do not transfer heat well like wood or plastic

34. D) Convection: Thermal energy transferred through fluids (liquids or gases)

35. 1) when an liquid or gas is heated it expands and its density decreases, and it rises

36. 2) cooler liquid or gas is compact and its density increases, so it sinks

37. 3) if a liquid or gas is heated from below then a convection current can form

38. E) Radiation: the transfer of thermal energy as waves

39. 1) only form of energy that can travel through space

40. 2) all the energy we get from the sun is in the form of radiation

41. 3) examples include radio waves, microwaves, infrared, visible light, ultra violet, x-rays, and gamma rays (electromagnetic spectrum)