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Consider the chair you are probably sitting on. The food you eat. The juices you drink. Each of these things, and everything else for that matter, is alike in some important ways.
Each is made of matter, which has mass. Mass is a form of energy. However, the energy of mass is not usable until a chemical reaction takes place. For example, energy is stored in a piece of wood, but this energy is not usable until a chemical reaction, such as burning, takes place. 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 great understanding that Albert Einstein summarized in 1905 in his now famous equation: E=mc2. Put simply, mass and energy are variations of each other. Mass is a visible form of energy and becomes pure energy when moving fast enough. The c2 in the equation stands for the particular speed at which matter is transformed 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, nuclear power, and almost everything else in, under, and around our world.
