How is E=mc^2 connected to the speed of light?

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In the mass-energy equivalent equation, E=mc^2, why is it related to the speed of light?
 
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That is the formula for rest energy predicted by Special Relativity.

From the postulates of SR (Invariance of c, physical laws are the same in all inertial frames) one can derive the equations describing energy:
E_{tot}=\gamma mc^2
E_k=(\gamma -1)mc^2
which lead to the conclusion that a mass has a rest energy E_0=mc^2 which is called the mass-energy equivalence.

So the the short answer is that it follows from the postulates of SR.

For a more in depth description detailing how the equation is derived, see
http://en.wikipedia.org/wiki/Mass-energy_equivalence#Background
 
Merry Christmas!

DeadCat_86 said:
In the mass-energy equivalent equation, E=mc^2, why is it related to the speed of light?

He DeadCat_86! Have a bouncy Christmas! :smile:

e is energy, which is ML2/T2, while m is of course just M,

so the conversion factor must have dimensions of L2/T2, ie it has to be a velocity squared …

and c is the only non-arbitrary velocity for such a general equation! :wink:
 
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tiny-tim said:
He DeadCat_86! Have a bouncy Christmas! :smile:

e is energy, which is ML2/T2, while m is of course just M,

so the conversion factor must have dimensions of L2/T2, ie it has to be a velocity squared …

and c is the only non-arbitrary velocity for such a general equation! :wink:

Dimensional analysis saves the day yet again!
 

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