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Consider the chair you’re probably sitting on. The food you eat. The juices you drink. Each of these things, and everything else, is alike in some important ways.
Each is made of matter. Matter has mass. Mass is a form of energy. However, the energy of mass can’t be used until a chemical reaction takes place. For example, energy is stored in a piece of wood. But this energy can’t be used until there’s a chemical reaction, such as burning. When wood is burned, energy is released in the form of heat. The heat can be used for many things, such as warming a room or toasting a marshmallow.
This is the big idea that Albert Einstein summed up in 1905. His famous equation is E=mc2. Put simply, mass and energy are different forms of each other. Mass is a form of energy you can see. It turns into pure energy when it’s moving fast enough. The c2 in the equation stands for the speed at which matter turns into energy. That speed is 186,000 (miles per second) squared – the speed of light multiplied by itself.
The idea in Einstein’s equation is key to understanding fission and nuclear power. Not to mention almost everything else about our world!
