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2 Imagine... You’ve been swimming for a long time Friends ask you to play volleyball

3 You say you don’t have the energy What exactly do you mean? What is energy?

4 Vocabulary Energy The ability to do work

5 Moving things is a type of work When you hit a volleyball You move it!

6 When you jump and run You move yourself! Playing volleyball, jumping, and running all take ENERGY

7 There are several types of energy 1.Mechanical Energy When something moves It is using mechanical energy

8 2.Heat Energy Heat energy passes heat from one object to another

9 3.Electric energy Electric energy makes light bulbs light up and radios play.

10 4.Chemical energy Gasoline has chemical energy. When gasoline is burned in a car’s engine, the chemical energy is changed to mechanical energy

11 The mechanical energy moves the car

12 Energy is not matter Because It does not have mass or take up space Matter takes up space

13 You cannot see energy but you can see what energy does Each kind of energy can change into other kinds of energy

14 All the energy in the world comes from the sun The sun’s energy is called Solar Energy

15 On Earth, solar energy is changed into other kinds of energy Nothing on Earth could live without energy from the sun

16 Plants could not live without solar energy Plants make their own food

17 Plants make food out of water from the soil and Gas in the air called carbon dioxide (CO 2 )

18 People eat the food that plants make Apples, potatoes, lettuce, celery, and beans are all plant foods that people eat

19 Without solar energy, people would not have any plants to eat

20 Some animals also eat plants Animals eat other animals that eat plants

21 Without plants, animals could not live There would be no animals for people to eat

22 You would not have chicken or hamburgers or fish to eat You would not have the things that animals produce, such as milk, eggs or wool

23 People and animals are warmed by the heat of the sun

24 When it is cold, people use fuels such as coal and oil to heat their homes. These fuels are made by solar energy

25 Coal and oil were formed from plants and animals that lived millions of years ago When the plants and animals died, their bodies became part of the Earth

26 The energy from these dead plants and animals became chemical energy in coal and oil

27 When coal and oil are burned, the stored chemical energy becomes heat energy