What does E(nergy) = m(ass) (times c^2) mean?

[sayetsu]

I know m isn't matter; it's inertial mass, but I don't know what that means or how it "equals" energy. I've never found an explanation I understood, so I thought I'd try asking here. Matter can be converted to energy, though, right? That's how nuclear bombs work, or hydrogen bombs...my recollection's a little fuzzy.

 

[PeroK]

Can you not find a good explanation on line?

 

[Ibix]

It means that a body of rest mass $m$ releases energy $E$ if converted to some form without rest mass (e.g. gamma radiation). Or alternatively that energy $E$ contributes $m$ to the mass of some system in its rest frame.

 

[mgkii]

Hi Sayetsu

There are literally hundreds of videos you can find; the challenge is finding the "good" ones - which will differ for most people depending on background etc

Based on your question I would try these two (in this order)
Special Relativity (E = mc2) Explained A Four minute reminder of what you asked

Why E=mc² is wrong An extra 6 minutes that either reminds you / tells you that there's a bit more to the formula that doesn't often get discussed.