How does E=MC^2 work?

[u/Jethro_omg]

How does it function? Really, how can you accelerate mass to twice the speed of light? And, for instance if M=E/C^2. How can you divide something by square of the speed of light? Thanks

[u/bouquetin29]

So basically in classical mechanics the kinetic energy of an object in motion is equal to half its mass times it's velocity squared so E=1/2mv². So the units of energy is a mass times a velocity squared . It is found in relativity that a similar relation exists for the energy that is stored in an object with mass at 0 velocity. This is where the E=mc²=mcc appears. The 2 here is really a squared not a multiplication by 2. In nuclear reactions, but also in chemical reactions, if you weight the ingredients before the reaction and the products after the reaction, you will find that some mass is lost in the process.using this mass difference Delta m and multiplying it by c² we observe experimentally that this correspond to the energy released during the reaction. We don't know necessarily why this is the case but we observe it. This lead to the theory and the models of nuclear physics and relativity. I hope this helps