What Does E=mc^2 Mean?

E=mc^2 is a version of Einstein's famous Relativity equation. Specifically, it means that energy is equal to mass multiplied by the speed of light squared. While seemingly simple, this relativity equation has many profound implications, such as the rule that no object with mass can ever go faster than the speed of light.

That's because the total energy of an object increases as its speed increases. As an object's speed reaches the speed of light its mass approaches infinity. This means that it would take an infinite amount of energy to accelerate an object to the speed of light.

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