Electricity is the most widely used form of energy. It's uses range from the miniature batteries that operate your wristwatch, to huge motors that power trains and ships. Electricity operates our lights, runs our refrigerators, and powers motors. Energy must first be changed to other forms of energy such as heat, light, or mechanical to be useful. You can't see electricity, but you can see what it does - like when you turn on a light.


Atoms make up all things.

You can't see atoms because they're so tiny, but you can imagine what they look like. Each atom is made up of PROTONS, NEUTRONS, and ELECTRONS. Protons have a positive (+) charge, electrons have a negative (-) charge, and neutrons have no charge. The protons and neutrons make up the NUCLEUS, or center of the atom. The electrons circle around the nucleus like planets orbit around the sun.

If an atom has the same number of protons and electrons it is balanced and has a neutral charge. When an electron gets knocked out of its orbit, it is called a free electron. This means the atom has a positive charge. The free electron may then join another balanced atom, giving it a negative charge. Atoms with the same charge move away from each other, but atoms with different charges attract each other.