58 L6-Incredible Energy

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Oxford Read and Discover level 6 Incredible Energy by Louise & Richard Spilsbury

Introduction Energy is incredible because we use it for everything that we do. Energy can make things work, make things move, and make things happen. People use energy to work and to play. When people do things like cook food, listen to music, and use a lamp, they are using heat energy, sound energy, and light energy. What types of energy can you see here? What type of energy makes televisions and computers work? What types of energy do you use every day? Discover! Now read and discover more about incredible energy!

Chapter 1 Energy Everywhere Energy is everywhere and energy is in everything. We can't make energy and we can't destroy it. When we use energy to make something happen, we don't lose it. It becomes a different type of energy. Converting Energy One type of energy can be converted into another. For example, when we move, we use energy from the food that we eat. When runners use this energy to run fast in a race, some of it is converted into heat energy. That's why runners look and feel so hot at the end of a race! Discover! When people run, only 25% of the energy in their legs is used to make them move. Most of it is converted into heat energy. Different Types of Energy There are many different types of energy, for example electrical energy and heat energy. Two important types of energy are kinetic energy and potential energy. Kinetic energy is a type of energy that's moving. All things that move have kinetic energy. Wind is moving air. We use the kinetic energy in wind to fly kites and to sail boats. Things that are not moving also have energy. Potential energy is stored energy. It's energy inside something that's waiting to be used. It's energy that has the potential to do work. We have potential energy stored in our bodies. When we run, some of this potential energy is converted into kinetic energy to make our legs move.

How Potential Energy Works When we stretch a rubber band, we give it energy. The energy that we use to stretch the rubber band is stored inside it as potential energy. When we let go of the rubber band, it moves. When we stretch the rubber band more, it has more potential energy, and it can move more. When we jump on a trampoline, this stretches the trampoline springs. This gives the springs potential energy. When the springs can't be stretched any more, this potential energy is converted into kinetic energy. The springs move back, and this throws us up into the air! springs From High to Low Some things have potential energy because they are high up. When we lift a picture off the floor and put it on a wall, some of the energy that we use for lifting goes into the picture. If the picture falls off the wall, that potential energy is converted into kinetic energy. When something is very high up, it has a lot of potential energy. The water at the top of a high waterfall has a lot of potential energy. When it falls, it moves very fast because it has a lot of kinetic energy. Discover! Angel Falls in Venezuela is the highest waterfall in the world. The water falls almost 1 kilometer from top to bottom!

Chapter 2 Heat Energy We use heat energy for many things. Heat energy makes our homes warm, cooks our food, and makes hot water that we can use for drinking and washing. How We Get Heat Energy We can get heat energy in different ways. Heat energy from the sun makes Earth warm. We can also get heat energy when we burn wood. When things move, some kinetic energy is converted into heat energy. Inside our body we make heat energy to keep us warm. When heat is added to something, its temperature gets higher. When something has a high temperature it's very hot. Things are cold when they have less heat energy. When something is cold, it has a low temperature. Inside Hot Things Everything in the world is made of parts called atonms. Atoms join together to make molecules. Atoms and molecules are so small that we can't see them, but they are inside everything— rocks, water, air, and people. When water is frozen, it becomes solid ice because it has very little heat energy. Molecules in ice are very near each other and they don't move very much. When heat energy is added to something, it makes the molecules inside move more. When heat energy is added to ice, molecules inside it move more. The ice melts and becomes liquid water again. If more heat is added to the water so that it boils, the molecules move so much that the water changes into a gas called steam.