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Energy comes in many forms

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Can you imagine a world without energy? You wouldn’t be able to play computer games, ride a bicycle or talk on the phone. Cars and trucks wouldn’t move. Lights wouldn’t shine. Plants wouldn’t grow. Without energy, nothing would happen!

Energy is the ability to change or move matter.

Just about everything you see, hear and feel depends on energy. Energy comes in many forms.

Chemical energy is energy that is released by a chemical reaction. The food you eat contains chemical energy that is released when you digest your meal. Wood, coal, gasoline and natural gas are fuels that contain chemical energy. When these fuels are burned, the chemical energy is released as heat.

Radiant energy is energy that can move through empty space. The sun and stars are very powerful sources of radiant energy. The heat and light given off by light bulbs and campfires are also forms of radiant energy.

Mechanical energy moves objects from place to place. You use mechanical energy when you kick a ball or turn the pedals of a bicycle. Other examples of mechanical energy include water flowing in a stream or tires rolling down a road.

Electrical energy comes from the electrons within atoms. It can be created at a power plant or inside a battery, and can power everything from remote-controlled cars to refrigerators. Lightning and static electricity are also forms of electrical energy.

Nuclear energy is energy contained in the nucleus at the center of an atom. Nuclear energy is released when nuclei are split apart into several pieces, or when they are combined to form a single, larger nucleus.

Meet the Atom

An atom is the smallest unit of matter. So far, scientists have found 112 different kinds of atoms. Everything in the world is made of different combinations of these atoms. Every atom has a nucleus in the center. Tiny particles called electrons travel around the nucleus. The flow of electrons produces electricity.




Energy. The ability to do work. People get energy from food. Your toaster and your washing machine get their energy from electricity.
Chemical energy. Energy that is released by a chemical reaction.
Chemical reaction. A process that changes one substance into another substance. Chemical reactions that take place during digestion change energy in food into substances that the body can use to do work.
Radiant energy. Any form of energy radiating from a source, such as heat from the sun or a campfire, or light from a bulb.
Mechanical energy. The energy of motion that can move objects from place to place.
Electrical energy. A form of energy that arises from the flow of electrons.
Nuclear energy or nuclear power. Energy that is released from splitting atoms of radioactive materials (such as uranium) and then harnessed to generate electricity.
Atom. The smallest unit of matter. Everything in the world is made of different combinations of atoms.
Nucleus. The center of an atom. The nucleus contains tiny particles called protons and neutrons. Orbiting around the nucleus are electrons.
Electrons. Basic particles that orbit the nucleus of an atom. Electrons have a negative electrical charge. The flow of electrons produces electricity.
Static electricity. A form of electrical energy that results from an imbalance of positive and negative charges.