E=mc2

[Tub]

Why is it not just E=mc? Why is the equation Squared?

[Klaynos]

It is a simplification of

E^2=p^2c^2 +m^2c^4

Which is derived in special relativity. 

Also, E=mc must be wrong as it fails dimensional analysis. 

[Tub]

Just now, Klaynos said:

It is a simplification of

E^2=p^2c^2 +m^2c^4

Which is derived in special relativity. 

Also, E=mc must be wrong as it fails dimensional analysis. 

Thanks.