E=mc2 How did Einstein come up with this formula? Also what does it mean?

Answer 1

I think it stems from earlier work with electrons and photoelectric effect. Basically, it states that matter is neither created or destroyed but can change between a mass object or free energy. Hence, energy is equivalent to a particular mass by a coeffecient of the speed of light squared.

Answer 2

He derived it from the conservation of momenta as things approach the speed of light. The actual math is HS algebra. The remarkable acheivement was in recognizing what happens to mass, momentum, and time as a rest mass approaches the speed of light. For an easy read on how Einstein did this, please check out the source.

What it means is that mass and energy are not distinct, they are simply manifestations of the same stuff. For this reason, in physics, we often say "mass-energy" rather than mass or energy by itself.

In a practical sense it means Mc^2 = (m1 + m2)c^2 + E; so that if m1 + m1 < M the difference (M - m1 - m2)c^2 = E And that's where fission power comes from. That difference between an atom of M mass and the mass of its children after splitting (m1 and m2) is the energy E released by that splittiing atom.

In fusion, the energy again comes from mass difference. But this time m1 + m2 > M; where M is the mass of the fused particle. Even so, we have [(m1 + m2) - M]c^2 = E in a fusion reaction.

Answer 3

Albert Einstein The deep connection Einstein discovered between energy and mass is expressed in the equation E=mc² . Here E represents energy, m represents mass, and c² is a very large number, the square of the speed of light.

Answer 4

He realized the concept of m = e/c^2 first, then realized E = mc2.

Time is linear, a single direction - present to past. The physics trilogy describes the basis of our reality, and it gives a clue as to why things operate as they do. The trilogy is: E = mc2, m = E/c2, and c2 = E/m. The last is that of a field of gravity, which is a field of physical time. This equation describes the "c^2" concept as being an energy/mass relationship, while the first two describe the basis of our existence itself is this very same value of "c2".

In the first equation the value of "c2" is the multiplier and in the second the divider. In each of these it is the basis of the equation itself. What this means is that all forms of energy and mass are composed of this value. Our universe and all within are composed of physical time "c2". It is for this reason the present moves into becoming the past at the rate it does, and this rate of change is the same throughout our universe. Every event moves from "present time" to that of the "past", which means our universe moves in a single direction.

Mass moving to the speed of light would change into electromagnetic energy. Mass would change from being a three dimensional entity into becoming that of physical time. This may be thought of as m = c^3, or a cube of time. A cube of time "c3", as I remember, is that of 1 kg. or 2.2 lbs.

Were all the mass of our universe converted into electromagnetic energy (of which it is composed), then it would have changed from a three dimensional universe into that of a single dimension. At that instant physical time would have ceased to exist, for it requires the presence of a mass to form the concept of time.

So, to answer your question in a sentence, our universe was created in such manner that its formation is of energy, which lowest value is that of c^2.

Answer 5

It comes from the relativistic expansion of the velocity correction formula:

v=v/ (1+(v/c)^2)^(1/2)

for the total energy of the sytem of the moving mass is KE

E= 1/2mv^2
=1/2 m v^2/ (1+(v/c) )^(-1/2)

after talyor expasion, you get

E=1/2mv^2+ mc^2 + some higher terms..

when v is relatively slower than c, we measure the rest energy as
total energy

E=mc^2

Answer 6

Einsetin wrote the theory of relativity while working at a Swiss patent office. He tied together several of his theories of energy motion and came up with an equation that said that mass and energy can be changed into each other without losing any energy or mass in the exchange. It is part of his theory of relativity and is only one of its parts.

Answer 7

I was reluctant to answer your question because I didn't want to confuse you further after all the other answers above. So I'll keep mine short and simple and straight to the point.

Einstein came up with E=mc² as a result of his General Theory of Relativity. Which, of course, is too elaborate to explain here.

What it means is that if you take a certain amount of matter (stuff) of a certain mass (denoted by the "m" in the formula) and if you were to convert all that matter into energy, the amount of energy you'll get (denoted by "E") is equal to m times c squared, where c is the speed of light.

This formula is proven in a nuclear reaction in which an atom is split, and the resulting fragments are "lighter" than the original piece. What has happened is that the "missing mass" is actually converted into energy.

Well, in a nuclear reactor or in a nuclear bomb, more than one atom is involved and so the amount of energy adds up to a very very very large amount. (Yeah, something like trillions upon trillions of atoms are involved :)

"m" is usually expressed in kg

"c" is usually 299792458 metres per second

and "E" is in Joules.

If you were to burn one gram of sugar the usual way, or eat it, the most energy you would get is roughly 16 kilojoules.

But if you were to convert all of it into energy by changing all its atoms into pure energy, you'll get about 90 trillion Joules. Too bad we haven't found a way to do that. Even in a nuclear reaction, not all of the matter/mass is converted into energy. But even with say 1% of it converted into energy, a lot of energy is given out, and in this example, it'll be almost one trillion joules. Unlike ordinary burning, in which a very very small percentage is used up to make energy; most of it ends up as ash and smoke. You burn up 1 gram of sugar and you get some heat along with very close to 1 gram of ash and smoke.

E=mc² also shows us that matter is a highly concentrated form of energy. It's like as though matter is energy concentrated and frozen. Lots and lots and lots of energy.

Sorry my answer is longer than I'd hoped. But I hope you have a better understanding now. Thanks for voting mine as Best Answer (*hint*hint*)

Answer 8

its simple-----the energy of an object is equal to that object's mass multiplied by the the (speed of light) squared. also it was not his mos important discovery which was the theory of relativity

Answer 9

it's a formula to predict the evil activities of rats. yes, rats. those furry little creatures. "E" stands for the evil activities of the rats. and "E" equals the mass of the rat in grams (represented by "m") times the amount of food the rat consumes in grams squared(represented by c2). einstein was just bored when he came up with that.

Answer 10

Well, one day, he was seated on the toilet...