1. How to Use This Presentation To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show”, or simply press F5 on the top row of your keyboard. To advance to the next slide click the left mouse button once. From the Chapter screen you can click on any section to go directly to that section’s presentation. Blank or “missing” areas of a slide will remain hidden until the left mouse button is clicked. You may exit the slide show at any time by pressing the Esc key Copyright © by Holt, Rinehart and Winston. All rights reserved.

2. Energy and Energy Resources Module M: Chapter 5 Section 1: What Is Energy? Section 2: Energy Conversions Section 3: Conservation of Energy Section 4: Energy Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

3. What Is Energy? Section 1 Bellringer Finish the following phrase: “Energy is the ability to ____.” Write your completed phrase in your science journal. We often use the words energy and power synonymously, but they have specific meanings. What is the distinction between energy and power? Copyright © by Holt, Rinehart and Winston. All rights reserved.

4. What Is Energy? Section 1 Objectives Explain the relationship between energy and work. Compare kinetic and potential energy. Describe the different forms of energy. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

5. What Is Energy? Section 1 Energy and Work: Working Together What Is Energy? In science, energy is the ability to do work. Energy Transfer When one object does work on another, energy is transferred from the first object to the second object. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

6. What Is Energy? Section 1 Kinetic Energy What Is Kinetic Energy? Kinetic energy is the energy of motion. Kinetic Energy Depends on Mass and Speed An object’s mass affects its kinetic energy, but its speed has an even greater effect on its kinetic energy than its mass does. KE = m x v 2 Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide 2

7. What Is Energy? Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Gravitational Potential Energy When you lift an object,you do work on it. You use a force that is against the force of gravity. When you do this, you transfer energy to the object and give the object gravitational potential energy. Calculating Gravitational Potential Energy Gravitational potential energy equals an object’s weight multiplied by its height. GPE = weight x height [m x g x h] Height Above What? Gravitational potential energy depends on your point of view. So, height is a measure of how far an object has to fall. Potential Energy End of Slide

8. What Is Energy? Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. What Is Mechanical Energy? Mechanical energy is the total energy of motion and position of an object. Mechanical Energy in a Juggler’s Pin The mechanical energy of an object remains the same unless it transfers some of its energy to another object. But even if the mechanical energy of an object stays the same, the potential energy or kinetic energy it has can increase or decrease. Mechanical Energy End of Slide

9. What Is Energy? Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Thermal Energy Thermal energy is all of the kinetic energy due to random motion of the particles that make up an object. Thermal energy is illustrated on the next slide. Chemical Energy Chemical energy is the energy of a compound that changes as its atoms are rearranged. Electrical Energy Electrical energy is the energy of moving electrons. Other Forms of Energy End of Slide

10. Thermal Energy in Water Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved.

11. What Is Energy? Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Sound Energy Sound energy is caused by an object’s vibrations. Light Energy Light energy is produced by the vibrations of electrically charged particles. Nuclear Energy Nuclear energy is the energy that comes from changes in the nucleus of an atom. Other Forms of Energy continued End of Slide

12. Energy Conversions Section 2 Bellringer What do the following objects have in common: a plant, a Bunsen burner, a pendulum. Can you think of three more objects that have the same common link? Record your guesses in your science journal. Copyright © by Holt, Rinehart and Winston. All rights reserved.

13. Energy Conversions Section 2 Objectives Describe an energy conversion. Give examples of energy conversions for the different forms of energy. Explain how energy conversions make energy useful. Explain the role of machines in energy conversions. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

14. Energy Conversions Section 2 Kinetic Energy and Potential Energy Copyright © by Holt, Rinehart and Winston. All rights reserved. Energy Conversions and Skateboarding Look at the next slide to see energy conversions taking place on a skateboarding half-pipe. The skateboarder’s potential energy will become kinetic energy as he speeds down the side of the half-pipe. Elastic Potential Energy The wound-up rubber band in a toy airplane has a kind of potential energy called elastic potential energy. When the rubber band is let go, the stored energy becomes kinetic energy, spins the propeller, and makes the airplane fly. End of Slide

15. Potential Energy and Kinetic Energy Section 2 Copyright © by Holt, Rinehart and Winston. All rights reserved.

16. Energy Conversions Section 2 Conversions Involving Chemical Energy Energy Conversions in Plants As shown on the next slide, photosynthesis uses light energy to make new substances that have chemical energy. The Process Continues Plants change light energy into chemical energy. The chemical energy in the food you eat is changed into another kind of chemical energy that your body can use. Your body then uses that energy to give you the kinetic energy that you use in everything you do. It’s an endless process—energy is always going somewhere! Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

17. From Light Energy to Chemical Energy Section 2 Copyright © by Holt, Rinehart and Winston. All rights reserved.

18. Energy Conversions Section 2 Why Energy Conversions Are Important Energy Conversions Are Necessary for Life Energy conversions are needed for everything we do. Heating our homes, getting energy from a meal, and many other things use energy conversions. Conversions Involving Electrical Energy You use electrical energy all of the time. When you listen to the radio, when you make toast, and when you take a picture with a camera, you use electrical energy. Electrical energy can easily be changed into other forms of energy. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

19. Energy Conversions Section 2 Energy and Machines Machines Can Change Energy Some machines change the energy put into them into other forms of energy. See how a bicycle does this on the next slide. Machines as Energy Converters Machines help you use energy by converting it into the form that you need. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

20. Energy Conversions In a Bicycle Section 2 Copyright © by Holt, Rinehart and Winston. All rights reserved.

21. Conservation of Energy Section 3 Bellringer Where does the energy come from to make a roller coaster car move? Where does all the energy go? Explain the meaning of the sentence, “All of the energy put into a process still exists somewhere at the end of that process.” Use the roller coaster example to illustrate your explanation in your science journal. Copyright © by Holt, Rinehart and Winston. All rights reserved.

22. Conservation of Energy Section 3 Objectives Explain how energy is conserved within a closed system. Explain the law of conservation of energy. Give examples of how thermal energy is always a result of energy conversion. Explain why perpetual motion is impossible. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

23. Conservation of Energy Section 3 Where Does the Energy Go? Copyright © by Holt, Rinehart and Winston. All rights reserved. Energy on a Roller Coaster To find out where a roller coaster’s original potential energy goes, you have to think about more than just the hills of the roller coaster. Friction plays a part too. Friction is a force that opposes motion between two surfaces that are touching. See how friction plays a part in roller coaster energy conversions on the next slide. End of Slide

24. Energy Conversions in a Roller Coaster Section 3 Copyright © by Holt, Rinehart and Winston. All rights reserved.

25. Conservation of Energy Section 3 Energy Is Conserved Within a Closed System Copyright © by Holt, Rinehart and Winston. All rights reserved. What Is a Closed System? A closed system is a group of objects that transfer energy only to each other. Law of Conservation of Energy According to the law of conservation of energy, energy cannot be created or destroyed. End of Slide

26. Conservation of Energy Section 3 No Conversion Without Thermal Energy Copyright © by Holt, Rinehart and Winston. All rights reserved. Perpetual Motion? No Way! People have sometimes tried to make a machine that would run forever without any additional energy. This perpetual motion machine would put out exactly as much energy as it takes in. But that’s impossible, because some waste thermal energy always results from energy conversions. Making Conversions Efficient In terms of energy conversions, energy efficiency is a comparison of the amount of energy before a conversion with the amount of useful energy after a conversion. End of Slide

27. Energy Resources Section 4 Bellringer Write the names of several different energy resources in your science journal. Predict which ones are nonrenewable (a finite supply) and renewable (an endless supply) resources. Copyright © by Holt, Rinehart and Winston. All rights reserved.

28. Energy Resources Section 4 Objectives Copyright © by Holt, Rinehart and Winston. All rights reserved. Name several energy resources. Explain how the sun is the source of most energy on Earth. Evaluate the advantages and disadvantages of using various energy resources. End of Slide

29. Energy Resources Section 4 Nonrenewable Resources Copyright © by Holt, Rinehart and Winston. All rights reserved. Uses of Fossil Fuels Oil and natural gas, shown on the next slide, as well as coal, are the most common fossil fuels. All fossil fuels contain stored energy from the sun, which can be converted into other kinds of energy. Electrical Energy from Fossil Fuels One way to generate electrical energy is to burn fossil fuels. Nuclear Energy Another way to generate electrical energy is to use nuclear energy. End of Slide

30. Formation of Fossil Fuels Section 4 Copyright © by Holt, Rinehart and Winston. All rights reserved.

31. Energy Resources Section 4 Renewable Resources Solar Energy Sunlight can be changed into electrical energy through solar cells, photo-voltaics. Energy from Water The sun causes water to evaporate and fall again as rain that flows through rivers. The potential energy of water in a reservoir can be changed into kinetic energy as the water flows through a dam. Wind Energy A wind turbine changes the kinetic energy of the air into electrical energy by turning a generator. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

32. Energy Resources Section 4 Renewable Resources continued Geothermal Energy Thermal energy caused by the heating of Earth’s crust is called geothermal energy. Some geothermal power plants pump water underground next to hot rock. The water returns to the surface as steam, which can then turn the turbine of a generator. Biomass Plants use and store energy from the sun. Organic matter, such as plants, wood, and waste, that can be burned to release energy is called biomass. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

33. Energy Resources Section 4 The Two Sides to Energy Resources Advantages and Disadvantages All energy resources have advantages and disadvantages. Choosing the Right Energy Resource Energy planning in all parts of the world requires careful consideration of energy needs and the availability and responsible use of resources. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

34. Energy and Energy Resources Chapter 9 Concept Map Copyright © by Holt, Rinehart and Winston. All rights reserved. Use the following terms to complete the concept map on the next slide: potential energy, position, mechanical energy, motion, kinetic energy, mass, machines.

35. Concept Map Chapter 9 Copyright © by Holt, Rinehart and Winston. All rights reserved.

36. Concept Map Chapter 9 Copyright © by Holt, Rinehart and Winston. All rights reserved.