Einstein's mass-energy relation

Relationship between mass (m) and energy (E) in Albert Einstein's special theory of relativity, expressed E = mc, where c equals 186,000 mi/second (300,000 km/second), the speed of light. Whereas mass and energy were viewed as distinct in earlier physical theories, in special relativity a body's mass can be converted into energy in accordance with Einstein's formula. Such a release of energy decreases the body's mass (see conservation law).

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