I know that E=MC2 means the energy is equal to the blah blah blah but what does the definition actually mean?

Question

E=MC2 means the energy is equal to the mass x the speed of light 2.... now what does THAT actually mean?

Answer 1

According to NASA
In essence, it states that there is an equivalence between mass and energy. This simple statement has many profound implications... such as no object with mass can ever go faster than the speed of light!

this equation is what is used to explain the special theory of relativity. It shows the relationship between energy and matter.

So it shows that people cannot travel faster than the speed of light. It also tells you how if you convert matter into energy you get a very powerful explosion. Dont you wonder why you need uranium and plutonium? They are very HEAVY/ LARGE molecular/atomic compounds. By using these really BIG compounds they result in a lot more energy from fission.

Answer 2

It means that you can convert the mass of an object into energy. The E on the left side of the equation is Energy the m on the right side is mass and c is the speed of light.
The speed of light c is a big number 3x10^8 m/s. The equation says that if you convert into energy even a small piece of matter you will get out an incredible amount of energy because you are multiplying that mass with the square of a large number (3x10^8 m/s) ^2 = 9 x10^16 m^2/s^2 or almost hundred million billion.
This conversion from matter to energy is not something that happens in everyday chemical reactions. The only time it happens is in reactions involving the nucleus or fundamental particles. For example inside the sun there are nuclear reactions where 4 protons (through a sequence of steps) are transformed in a helium nucleus plus other smaller particles.
The amazing thing is that if you compare the masses of the starting ingredients (the 4 protons) with the final product of the reaction (the helium nucleus plus smaller particles) the mass of the starting products is slightly bigger.
Where did the missing mass go?
Well it was transformed into energy according E=mc^2.
It is a tiny amount of missing mass but because you are multiplying that mass by a large number you will get a big amount of energy per reaction.
This mechanism is the source of energy for the sun, energy that eventually reaches us on earth in the form of heat and light.
Nuclear reactions like nuclear decay also involve such an equation. E=m c^2 is the power behind the atomic bomb.
Also what is interesting is that you can go the other way around. You can convert a large amount of energy into mass.
This is done all the time in particle accelerators and it was done by the universe during the Big Bang.
In the beginning it was all light.
That light was converted into mass (that makes the stars, planets and us) according E=m c^2, well actually m= E/ c^2, to get a small mass you need a lot of energy.
The equation was derived by Einstein while he was studying the properties of motion of an object traveling close to the speed of light. The equation was a consequence of special relativity and Einstein wrote an article almost as an addendum to his main article on relativity (published 100 years ago) where he derived the E=mc^2.
People didn't understand the consequences of such an equation until they explored the properties of atomic nuclei and realized that some of the mass was converted into energy in nuclear reactions exactly according to Einstein's equation.
This was a very bad time for such a discovery because it was at the beginning of WW II. Germany, that had among the best scientists in the world rushed to build an atomic bomb but even if German scientists had an head start they failed.
The fear that Germany would build an atomic bomb before anybody else pushed USA to develop an atomic program that lead to Hiroshima and Nagasaki.
You know the rest of the story, I'm sure.

Answer 3

This equation is relevant when discussing conservation laws. Before Einstein, there were two conservation laws: conservation of mass and conservation of energy. In any process, the total mass would stay the same and the energy content would stay the same. What Einstein found out is that these conservation laws were not exactly accurate, but that a small amount of mass could be lost in some reactions and a large amount of energy would be released or vice versa.

Now, there is just one conservation law where there was two. A particle enters into the new law as an energy term that can be found from E^2=m^2 c^4 +p^2 c^2 where m is the mass, p the momentum, and c is the speed of light. If the particle is not moving, p=0 and you get E=mc^2. If the particle is massless (like a photon), m=0 and you get E=pc.

Answer 4

I hope I can keep this simple.

E = energy
m = mass
c is the speed of light

You know the speed of light is 186000 miles per second.
that is 982,080,000 feet per second.
this number squared is 964481126400000000 ft^2 / sec^2

Now lets take something (doesn't matter what it is, a rock, a chunk of steel, paper) that weighs 32.2 pounds (to make it easy since gravity acceleration is 32.2 ft^2/sec^2)
The mass of this would be 32.2 lbforce/32.2 f^2/s^2 = 1 lbmass.

This means if you could release the energy in this 1 lbmass rock, you would release 964,481,126,400,000,000 lb of force. Enough force to wipe out a few citys, easily. They use plutonium (a type of metal) for nuclear bombs because it is easier to get the energy to release. A rock is just too stable. But if you get about 7 pounds of plutonium it is very unstable (about 7 pounds is called critical mass. Anything more than critical mass will cause a nuclear explosion. In fact, that's basically how the get the nuclear reaction started. They take just enough so it is under critical mass - then to ignite it, they just add a little more - and KABOOM - of course this is very simplified explanation) And in an actual nuclear explosion, only a very, very small amount of plutonium is converted into pure energy, I think it is less than 1%.

So 7 lb plutonium divided by 32.2 gives 0.2174 lbmass.
0.2174 lbmass times c^2 = 209678196879360000 lbforce. At 1% efficiency this comes out to about 2096781968793600 lbs force. This is how much energy you see explode when you see a nuclear bomb go off.

Answer 5

This equation relates a lots of things in just 2 variables, that is mass and energy, and as stated in the many answers given here, it implies that mass and energy are interconvertible.
But there is more to this equation than simply this.
Why was the balancing factor of the equation taken as speed of light? It was done so, coz according to Einstein if a particle travels with the speed of light, its mass should increase.
But since it is not possible for ordinary objects to travel at that speed, the obvious mass gain is never visible.
And if the total mass of an object were to be converted into energy and that energy be totally kinetic in nature then it would acquire the speed of light.

Answer 6

"During a chemical reaction, the amount of energy released is equal to the amount of mass lost during the reaction multiplied by the square of speed of light"
No problem if you don't get it the first time because Einstein presented his explanation for the first time no other scientist was able to answer it.
There is a law called "the law of conservation of mass."it says that mass can neither be created nor destroyed BUT in a closed system.In a open system some of the mass is lost to the environment in the form of energy,usually heat and light.
The amount of energy released is sorted out by this formula.

E=MC^2.

This is applied in the manufacture of nuclear energy.Now its up to us how we use it.Either to produce electricity or to make atom bombs.

Answer 7

The Soviet/Russian academic S. Vavilov suggested an
interesting idea. In his book 'Isaac Newton' he wrote.
The force, according to the Newton,s Second Law,
is equal to : F= ma.
This force is possible to consider as absolute independent
quantity - impulse. When in case with light quanta
the impulse is equal to: mc.
He continued.
Let us now imagine that light quanta falls on a black body,
and it absolutely absorbs this light quanta
( it means light quanta stops).
Then, according to the Lebedev,s law, light quanta
renders pressure on the black body: E/c.
Therefore it is possible to write: mc=E/c.
It means that the stopping
light quanta has not rest mass equal to zero,
but it potential energy/mass is :
M=E/c^2. (E=Mc^2).
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The potential energy/mass of light quanta
can transform in its kinetic energy.
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http://www.socratus.com

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Answer 8

material and energy like two faces for one coin every body have an energy equall to MC2 so the effect of macroscopic body tow small , but in microscopic bode such as electron we can see great result of this equation , because micro... can be accelerated in high velocity

Answer 9

It refers to the first law of thermodynamics...that energy can neither be created nor destroyed.

E=MC^2 shows that matter is a type of energy, so that even when energy seems to be 'created', as in radioactivity, it's actually just a state change.

Answer 10

it means Energy & Mass is the same,only different