E=mc² Calculator - Sonraji.com

E = mc² Calculator

E = mc²

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About E = mc²

Einstein's famous equation E = mc² expresses the equivalence of mass and energy. This equation revolutionized physics by showing that mass can be converted into energy, and vice versa.

Where:

E is energy (in joules, J)
m is mass (in kilograms, kg)
c is the speed of light in a vacuum (299,792,458 meters per second)

The equation shows that even a small amount of mass can be converted into an enormous amount of energy, since the speed of light squared (c²) is a very large number: approximately 9 × 10¹⁶ m²/s².

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Historical Background

Albert Einstein published this equation as part of his theory of special relativity in 1905. The equation was revolutionary because it united the concepts of mass and energy, which had previously been considered entirely separate physical quantities.

Applications

E = mc² explains many natural phenomena and has practical applications in:

Nuclear Energy: Both nuclear fission (in power plants) and fusion (in stars) convert a small amount of mass into a large amount of energy.
Particle Physics: In particle accelerators, mass can be converted to energy and back to mass in the form of different particles.
Astrophysics: Stars generate energy by converting mass to energy through nuclear fusion.
Medical Applications: PET scans and radiation therapy rely on principles related to the mass-energy equivalence.

Mass Defect

In nuclear reactions, the mass of the products is slightly less than the mass of the reactants. This "missing" mass (mass defect) has been converted into energy according to E = mc².

Relativistic Mass

In Einstein's full theory, mass increases with velocity according to the formula m = m₀/√(1-v²/c²), where m₀ is the rest mass. As an object approaches the speed of light, its mass would approach infinity, requiring infinite energy to accelerate further. This is why nothing with mass can reach the speed of light.