Can the smart people of SW explain to me "e = mc squared"? Specifically,

I know that it is Einstein's famous formula and means "energy equals mass times the square of the speed of light". What I don't get is how the measurement works. Mass is measured in units of weight, right? Speed, in units of time and distance. How is energy measured by this method? Like, if we're doing metric, let's say you have a mass of one kilogram, and the speed of light is 299,792,458 metres per second. Square that and you get 89,875,517, 873,681,764 kilometres per second... or is it square kilometres per square second?? And then your energy outcome is 89,875,517, 873,681,764 kilograms-kilometres-seconds?? What does that even mean, other than "really really big"? I am sure there are many SWeeps here in the sciences who actually understand it so please explain it to me and the rest of us who dropped math and science after high school. Thank you!

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Harmonium1923 · 51-55, M

I had to go look this up. Energy is measured in joules, which is a measurement equivalent to kg * (meters squared / seconds squared). So mass is measured in KG and the speed of light in m/s.

You’re right about the magnitude. There is an extraordinary amount of energy stored in the atoms that make up an objects mass.

ServantOfTheGoddess · 61-69, M

@Harmonium1923 Thank you. I feel like I still need more explaining. Does the joule express something like how fast you could make an object of that weight move with this amount of energy??

Harmonium1923 · 51-55, M

@ServantOfTheGoddess I think we’re gonna need an actual scientist to get us to the next level.

helenS · 36-40, F

@ServantOfTheGoddess If a 1kg object moves at a speed of 1m/s, its kinetic energy will be 0.5 Joule.
1J = 1 kg * m * m / (s * s)

ServantOfTheGoddess · 61-69, M

@helenS thank you!