Energy Chapter 15

1. EnergyChapter 15 Lesson 1: What are kinetic and potential energy? Lesson 2: What are some forms of energy? Lesson 3: How is heat transferred? Lesson 4: How do people use energy resources?

2. Lesson One Vocabulary • Energy- the ability to cause a change in matter • Kinetic Energy- energy in motion • Potential Energy- energy an object has because of its condition or position • Energy Transfer- the movement of energy from one place or object to another.

3. Lesson 1: Energy • Energy is something that causes a change in matter. • Energy causes many kinds of changes. • One kind of change is movement. • Energy comes from food, fuels, and other sources.

4. Energy has different forms. It can change from one form to another. But energy cannot be made or destroyed. It can only change. This is called: The Law of Conservation of Energy. Lesson 1: Energy

5. We can classify all the kinds of energy into two major groups: Kinetic energy is the energy of motion. Potential energy is energy an object has because of where it is. Lesson 1: Kinetic and potential energy

6. Energy can move between 2 objects. Energy can also move from one place to another. The movement of energy from one place to another is called energy transfer. Lesson 1: Energy transfer

7. Lesson 2 Vocabulary • Solar Energy- energy that comes from the sun • Light- Radiation that we can see • Chemical Energy- Energy that can be released by a chemical reaction • Mechanical Energy- combination of all the kinetic and potential energy something has • Electric Energy- energy that comes from an electric current

8. Lesson 2: Forms of energy • Solar energy is energy that comes from the sun. • We can see some kinds of solar energy in the form of light. • Heat is also a form of solar energy that we could not live on Earth without.

9. Lesson 2: Forms of energy • Chemical energy is energy that can be released by a chemical reaction. • The energy stored in matter is potential energy. • A chemical reaction changes this potential energy into kinetic energy.

10. When a car is moving, it has kinetic energy. A car also has potential energy in its fuel. The sum of all the potential and kinetic energy something has is called mechanical energy. Moving objects have both potential and kinetic energy at the same time. Lesson 2: Forms of energy

11. Some energy comes in the form of electrons that make up atoms. This energy is called electric energy. Electricity comes from moving electrons. We use electricity every day! Lesson 2: Forms of Energy

12. Lesson 2: Forms of energy • Sound is a form of energy we use every day. • Sound comes from vibrations in matter. • The vibrations spread out in all directions. • These vibrations travel through the air and to our ears.

13. Energy changes all the time. For example, an electric radio uses electric energy to play music that you can hear. Some of the electric energy is changed to sound energy. Radios with digital clocks also change some electric energy to light. Lesson 2: Forms of energy

14. Lesson 3 Vocabulary • Heat- transfer of thermal energy between objects with different temperatures • System- a group of separate elements that work together to accomplish something • Conduction- transfer of heat from one object directly to another • Convection- transfer of heat through the movement of a gas or a liquid • Radiation- transfer of energy by means of waves that move through mater and space • Reflection- the bouncing of heat or light off an object

15. Thermal energy is one form of energy. Heat is the transfer of thermal energy between objects with different temperatures. Thermal energy always moves from warmer objects to cooler objects. Temperature measures this form of kinetic energy. Lesson 3: Heat transfer

16. Lesson 3: Heat transfer • Thermal energy travels in a system. • A system is a group of parts that work together. • When you heat water on a stove: The pot, the water, and the stove make up a system.

17. Lesson 3: Heat transfer • Heat can move through a system in three ways: • Conduction is the transfer of heat from one object directly to another, cooler object. • Convection is the transfer of heat by the movement of gas or liquid. • Radiation transfers heat by waves that move through matter and space. (Radiation is different than conduction and convection because it does not need matter to transfer heat.) • These waves can also bounce off objects and this is a reflection.

18. Lesson 3: Heat transfer • Examples:

19. Heat can move easily through some objects. These objects are called conductors. Metal is a good conductor of heat. Heat does not move easily through other objects. Insulators stop or slow heat from leaving an object or keep heat from reaching an object. Lesson 3: Heat transfer

20. Lesson 4 Vocabulary • Fossil- remains or traces of the past life, found in sedimentary rock • Resource- material that can be used to satisfy a need • Nonrenewable resource- a resource that, once used, can NOT be replaced in a reasonable amount of time • Renewable resource- a resource that can be replaced within a reasonable amount of time • Pollution- a waste product that harms living things and damages an ecosystem

21. A fossil is the remains or traces of past life. Fossils are found in sedimentary rock and come from once-living things. Examples of fossils are coal, oil, and natural gas. These fuels can be burned to make heat and produce other forms of energy. Materials like fossil fuels, that can be used to satisfy our needs are called resources. Lesson 4: How do people use energy resources?

22. Lesson 4:How do people use energy resources? • Fossil fuels form over thousands of years and cannot be replaced quickly if they are used up. • A resource that cannot be replaced in a reasonable amount of time is a nonrenewable resource. • One way to make fossil fuels last longer is to practice conservation. • Conservation means using less of something to make the supply last longer.

23. Some resources can be replaced easily and are called renewable resources. Solar wind, and water energy are renewable resources. Scientists are working to find better, low-cost ways to use renewable energy resources. Lesson 4:How do people use energy resources?

24. Lesson 4:How do people use energy resources? • Using renewable resources reduces the amount of pollution in the environment as well. • Pollution is anything that dirties or harms the environment. • Conserving fossil fuels reduces pollution.

25. Comprehension Questions: • Some resources can be replaced in a short amount of time, but _________ fuels took thousands of years to form. • Using a lot of fuel is the opposite of practicing _____________. • The time it takes to replace a resource determines if it is renewable or _______________. • Conserving fossil fuels reduces the amount of ____________ in the environment.