# What $E=mc^2$ has to do with nuclear formation?

I am a bit confused that what actually the Einstein's equation meant to describe binding energy wht is that $c^2$ for as when nucleon combine what is the need of speed of light in equation?

• The $c$ in relativity isn't really the speed of light. See physics.stackexchange.com/q/35404 . Also, $E=mc^2$ is not specifically about nuclear reactions. It also applies when you burn a match. It applies to any form of energy. – Ben Crowell Mar 25 '18 at 18:35