Energy = mass * speed of light squared

Mass and energy are essentially the same thing, mass is just congealed energy. This equation means that if you have a one kilogram object and you were to convert it into pure energy, you would have c squared (about 90,000,000,000,000,000) joules of energy. Conversely, if you took c squared joules of energy and converted it to pure mass, you would have one kilogram.

E=mc^2, simply defines the mass-energy equivalence . It is a concept that mass of an object is a measure of its energy content. This proportionality of mass-and energy arises form Einstein's concept of special relativity. In terms of the equation E is energy, m is mass, and c is the speed of light. The equation also states that any object has a certain energy, even when it's stationary.

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