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Mass–Energy Equivalence (E = mc²)

E = m·c²

What it means

Einstein's famous equation states that mass and energy are interchangeable, with the speed of light squared as the conversion factor.

Variables

SymbolQuantitySI unit
EenergyJ
mmasskg
cspeed of lightm/s

Worked example

Given m = 1 kg, c = 2.9980e+8 m/s, solve for E:

E = 8.9880e+16 J

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